Refactor for readability

.cargo/config.toml

@@ -8,7 +8,3 @@ benchmark = "bench -p ruff_benchmark --bench linter --bench formatter --"
 # See: https://github.com/astral-sh/ruff/issues/11503
 [target.'cfg(all(target_env="msvc", target_os = "windows"))']
 rustflags = ["-C", "target-feature=+crt-static"]
-
-[target.'wasm32-unknown-unknown']
-# See https://docs.rs/getrandom/latest/getrandom/#webassembly-support
-rustflags = ["--cfg", 'getrandom_backend="wasm_js"']

.github/ISSUE_TEMPLATE/1_bug_report.yaml

@@ -1,31 +0,0 @@
-name: Bug report
-description: Report an error or unexpected behavior
-body:
-  - type: markdown
-    attributes:
-      value: |
-        Thank you for taking the time to report an issue! We're glad to have you involved with Ruff.
-
-        **Before reporting, please make sure to search through [existing issues](https://github.com/astral-sh/ruff/issues?q=is:issue+is:open+label:bug) (including [closed](https://github.com/astral-sh/ruff/issues?q=is:issue%20state:closed%20label:bug)).**
-
-  - type: textarea
-    attributes:
-      label: Summary
-      description: |
-        A clear and concise description of the bug, including a minimal reproducible example.
-
-        Be sure to include the command you invoked (e.g., `ruff check /path/to/file.py --fix`), ideally including the `--isolated` flag and
-        the current Ruff settings (e.g., relevant sections from your `pyproject.toml`).
-
-        If possible, try to include the [playground](https://play.ruff.rs) link that reproduces this issue.
-
-    validations:
-      required: true
-
-  - type: input
-    attributes:
-      label: Version
-      description: What version of ruff are you using? (see `ruff version`)
-      placeholder: e.g., ruff 0.9.3 (90589372d 2025-01-23)
-    validations:
-      required: false

.github/ISSUE_TEMPLATE/2_rule_request.yaml

@@ -1,10 +0,0 @@
-name: Rule request
-description: Anything related to lint rules (proposing new rules, changes to existing rules, auto-fixes, etc.)
-body:
-  - type: textarea
-    attributes:
-      label: Summary
-      description: |
-        A clear and concise description of the relevant request. If applicable, please describe the current behavior as well.
-    validations:
-      required: true

.github/ISSUE_TEMPLATE/3_question.yaml

@@ -1,18 +0,0 @@
-name: Question
-description: Ask a question about Ruff
-labels: ["question"]
-body:
-  - type: textarea
-    attributes:
-      label: Question
-      description: Describe your question in detail.
-    validations:
-      required: true
-
-  - type: input
-    attributes:
-      label: Version
-      description: What version of ruff are you using? (see `ruff version`)
-      placeholder: e.g., ruff 0.9.3 (90589372d 2025-01-23)
-    validations:
-      required: false

.github/ISSUE_TEMPLATE/config.yml

@@ -1,8 +1,2 @@
-blank_issues_enabled: true
-contact_links:
-  - name: Documentation
-    url: https://docs.astral.sh/ruff
-    about: Please consult the documentation before creating an issue.
-  - name: Community
-    url: https://discord.com/invite/astral-sh
-    about: Join our Discord community to ask questions and collaborate.
+# This file cannot use the extension `.yaml`.
+blank_issues_enabled: false

.github/ISSUE_TEMPLATE/issue.yaml

@@ -0,0 +1,22 @@
+name: New issue
+description: A generic issue
+
+body:
+  - type: markdown
+    attributes:
+      value: |
+        Thank you for taking the time to report an issue! We're glad to have you involved with Ruff.
+
+        If you're filing a bug report, please consider including the following information:
+
+        * List of keywords you searched for before creating this issue. Write them down here so that others can find this issue more easily and help provide feedback.
+        e.g. "RUF001", "unused variable", "Jupyter notebook"
+        * A minimal code snippet that reproduces the bug.
+        * The command you invoked (e.g., `ruff /path/to/file.py --fix`), ideally including the `--isolated` flag.
+        * The current Ruff settings (any relevant sections from your `pyproject.toml`).
+        * The current Ruff version (`ruff --version`).
+
+  - type: textarea
+    attributes:
+      label: Description
+      description: A description of the issue

.github/renovate.json5

@@ -95,7 +95,14 @@
       matchManagers: ["cargo"],
       matchPackageNames: ["strum"],
       description: "Weekly update of strum dependencies",
-    }
+    },
+    {
+      groupName: "ESLint",
+      matchManagers: ["npm"],
+      matchPackageNames: ["eslint"],
+      allowedVersions: "<9",
+      description: "Constraint ESLint to version 8 until TypeScript-eslint supports ESLint 9", // https://github.com/typescript-eslint/typescript-eslint/issues/8211
+    },
   ],
   vulnerabilityAlerts: {
     commitMessageSuffix: "",

.github/workflows/ci.yaml

@@ -280,7 +280,7 @@ jobs:
 
   cargo-build-msrv:
     name: "cargo build (msrv)"
-    runs-on: depot-ubuntu-latest-8
+    runs-on: ubuntu-latest
     needs: determine_changes
     if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 20
@@ -430,7 +430,7 @@ jobs:
           name: ruff
           path: target/debug
 
-      - uses: dawidd6/action-download-artifact@v8
+      - uses: dawidd6/action-download-artifact@v7
         name: Download baseline Ruff binary
         with:
           name: ruff
@@ -712,7 +712,7 @@ jobs:
           just test
 
   benchmarks:
-    runs-on: ubuntu-24.04
+    runs-on: ubuntu-22.04
     needs: determine_changes
     if: ${{ github.repository == 'astral-sh/ruff' && !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 20

.github/workflows/daily_property_tests.yaml

@@ -47,7 +47,6 @@ jobs:
         run: |
           export QUICKCHECK_TESTS=100000
           for _ in {1..5}; do
-            cargo test --locked --release --package red_knot_python_semantic -- --ignored list::property_tests
             cargo test --locked --release --package red_knot_python_semantic -- --ignored types::property_tests::stable
           done
 

.github/workflows/mypy_primer.yaml

@@ -1,93 +0,0 @@
-name: Run mypy_primer
-
-permissions: {}
-
-on:
-  pull_request:
-    paths:
-      - "crates/red_knot*/**"
-      - "crates/ruff_db"
-      - "crates/ruff_python_ast"
-      - "crates/ruff_python_parser"
-      - ".github/workflows/mypy_primer.yaml"
-      - ".github/workflows/mypy_primer_comment.yaml"
-
-concurrency:
-  group: ${{ github.workflow }}-${{ github.ref_name }}-${{ github.event.pull_request.number || github.sha }}
-  cancel-in-progress: true
-
-env:
-  CARGO_INCREMENTAL: 0
-  CARGO_NET_RETRY: 10
-  CARGO_TERM_COLOR: always
-  RUSTUP_MAX_RETRIES: 10
-
-jobs:
-  mypy_primer:
-    name: Run mypy_primer
-    runs-on: ubuntu-24.04
-    timeout-minutes: 20
-    steps:
-      - uses: actions/checkout@v4
-        with:
-          path: ruff
-          fetch-depth: 0
-          persist-credentials: false
-
-      - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@v5
-
-      - uses: Swatinem/rust-cache@v2
-        with:
-          workspaces: "ruff"
-      - name: Install Rust toolchain
-        run: rustup show
-
-      - name: Install mypy_primer
-        run: |
-          uv tool install "git+https://github.com/astral-sh/mypy_primer.git@add-red-knot-support"
-
-      - name: Run mypy_primer
-        shell: bash
-        run: |
-          cd ruff
-
-          echo "new commit"
-          git rev-list --format=%s --max-count=1 "$GITHUB_SHA"
-
-          MERGE_BASE="$(git merge-base "$GITHUB_SHA" "origin/$GITHUB_BASE_REF")"
-          git checkout -b base_commit "$MERGE_BASE"
-          echo "base commit"
-          git rev-list --format=%s --max-count=1 base_commit
-
-          cd ..
-
-          # Allow the exit code to be 0 or 1, only fail for actual mypy_primer crashes/bugs
-          uvx mypy_primer \
-            --repo ruff \
-            --type-checker knot \
-            --old base_commit \
-            --new "$GITHUB_SHA" \
-            --project-selector '/(mypy_primer|black|pyp|git-revise|zipp|arrow)$' \
-            --output concise \
-            --debug > mypy_primer.diff || [ $? -eq 1 ]
-
-          # Output diff with ANSI color codes
-          cat mypy_primer.diff
-
-          # Remove ANSI color codes before uploading
-          sed -ie 's/\x1b\[[0-9;]*m//g' mypy_primer.diff
-
-          echo ${{ github.event.number }} > pr-number
-
-      - name: Upload diff
-        uses: actions/upload-artifact@v4
-        with:
-          name: mypy_primer_diff
-          path: mypy_primer.diff
-
-      - name: Upload pr-number
-        uses: actions/upload-artifact@v4
-        with:
-          name: pr-number
-          path: pr-number

.github/workflows/mypy_primer_comment.yaml

@@ -1,97 +0,0 @@
-name: PR comment (mypy_primer)
-
-on: # zizmor: ignore[dangerous-triggers]
-  workflow_run:
-    workflows: [Run mypy_primer]
-    types: [completed]
-  workflow_dispatch:
-    inputs:
-      workflow_run_id:
-        description: The mypy_primer workflow that triggers the workflow run
-        required: true
-
-jobs:
-  comment:
-    runs-on: ubuntu-24.04
-    permissions:
-      pull-requests: write
-    steps:
-      - uses: dawidd6/action-download-artifact@v8
-        name: Download PR number
-        with:
-          name: pr-number
-          run_id: ${{ github.event.workflow_run.id ||  github.event.inputs.workflow_run_id }}
-          if_no_artifact_found: ignore
-          allow_forks: true
-
-      - name: Parse pull request number
-        id: pr-number
-        run: |
-          if [[ -f pr-number ]]
-          then
-            echo "pr-number=$(<pr-number)" >> "$GITHUB_OUTPUT"
-          fi
-
-      - uses: dawidd6/action-download-artifact@v8
-        name: "Download mypy_primer results"
-        id: download-mypy_primer_diff
-        if: steps.pr-number.outputs.pr-number
-        with:
-          name: mypy_primer_diff
-          workflow: mypy_primer.yaml
-          pr: ${{ steps.pr-number.outputs.pr-number }}
-          path: pr/mypy_primer_diff
-          workflow_conclusion: completed
-          if_no_artifact_found: ignore
-          allow_forks: true
-
-      - name: Generate comment content
-        id: generate-comment
-        if: steps.download-mypy_primer_diff.outputs.found_artifact == 'true'
-        run: |
-          # Guard against malicious mypy_primer results that symlink to a secret
-          # file on this runner
-          if [[ -L pr/mypy_primer_diff/mypy_primer.diff ]]
-          then
-              echo "Error: mypy_primer.diff cannot be a symlink"
-              exit 1
-          fi
-
-          # Note this identifier is used to find the comment to update on
-          # subsequent runs
-          echo '<!-- generated-comment mypy_primer -->' >> comment.txt
-
-          echo '## `mypy_primer` results' >> comment.txt
-          if [ -s "pr/mypy_primer_diff/mypy_primer.diff" ]; then
-            echo '<details>' >> comment.txt
-            echo '<summary>Changes were detected when running on open source projects</summary>' >> comment.txt
-            echo '' >> comment.txt
-            echo '```diff' >> comment.txt
-            cat pr/mypy_primer_diff/mypy_primer.diff >> comment.txt
-            echo '```' >> comment.txt
-            echo '</details>' >> comment.txt
-          else
-            echo 'No ecosystem changes detected ✅' >> comment.txt
-          fi
-
-          echo 'comment<<EOF' >> "$GITHUB_OUTPUT"
-          cat comment.txt >> "$GITHUB_OUTPUT"
-          echo 'EOF' >> "$GITHUB_OUTPUT"
-
-      - name: Find existing comment
-        uses: peter-evans/find-comment@v3
-        if: steps.generate-comment.outcome == 'success'
-        id: find-comment
-        with:
-          issue-number: ${{ steps.pr-number.outputs.pr-number }}
-          comment-author: "github-actions[bot]"
-          body-includes: "<!-- generated-comment mypy_primer -->"
-
-      - name: Create or update comment
-        if: steps.find-comment.outcome == 'success'
-        uses: peter-evans/create-or-update-comment@v4
-        with:
-          comment-id: ${{ steps.find-comment.outputs.comment-id }}
-          issue-number: ${{ steps.pr-number.outputs.pr-number }}
-          body-path: comment.txt
-          edit-mode: replace

.github/workflows/pr-comment.yaml

@@ -16,7 +16,7 @@ jobs:
     permissions:
       pull-requests: write
     steps:
-      - uses: dawidd6/action-download-artifact@v8
+      - uses: dawidd6/action-download-artifact@v7
         name: Download pull request number
         with:
           name: pr-number
@@ -32,7 +32,7 @@ jobs:
             echo "pr-number=$(<pr-number)" >> "$GITHUB_OUTPUT"
           fi
 
-      - uses: dawidd6/action-download-artifact@v8
+      - uses: dawidd6/action-download-artifact@v7
         name: "Download ecosystem results"
         id: download-ecosystem-result
         if: steps.pr-number.outputs.pr-number

.github/workflows/publish-playground.yml

@@ -35,8 +35,6 @@ jobs:
           cache: "npm"
           cache-dependency-path: playground/package-lock.json
       - uses: jetli/wasm-pack-action@v0.4.0
-        with:
-          version: v0.13.1
       - uses: jetli/wasm-bindgen-action@v0.2.0
       - name: "Run wasm-pack"
         run: wasm-pack build --target web --out-dir ../../playground/src/pkg crates/ruff_wasm
@@ -51,7 +49,7 @@ jobs:
         working-directory: playground
       - name: "Deploy to Cloudflare Pages"
         if: ${{ env.CF_API_TOKEN_EXISTS == 'true' }}
-        uses: cloudflare/wrangler-action@v3.14.0
+        uses: cloudflare/wrangler-action@v3.13.1
         with:
           apiToken: ${{ secrets.CF_API_TOKEN }}
           accountId: ${{ secrets.CF_ACCOUNT_ID }}

.github/workflows/publish-wasm.yml

@@ -35,8 +35,6 @@ jobs:
       - name: "Install Rust toolchain"
         run: rustup target add wasm32-unknown-unknown
       - uses: jetli/wasm-pack-action@v0.4.0
-        with:
-          version: v0.13.1
       - uses: jetli/wasm-bindgen-action@v0.2.0
       - name: "Run wasm-pack build"
         run: wasm-pack build --target ${{ matrix.target }} crates/ruff_wasm

.pre-commit-config.yaml

@@ -5,7 +5,6 @@ exclude: |
     .github/workflows/release.yml|
     crates/red_knot_vendored/vendor/.*|
     crates/red_knot_project/resources/.*|
-    crates/ruff_benchmark/resources/.*|
     crates/ruff_linter/resources/.*|
     crates/ruff_linter/src/rules/.*/snapshots/.*|
     crates/ruff_notebook/resources/.*|
@@ -24,7 +23,7 @@ repos:
       - id: validate-pyproject
 
   - repo: https://github.com/executablebooks/mdformat
-    rev: 0.7.22
+    rev: 0.7.21
     hooks:
       - id: mdformat
         additional_dependencies:
@@ -37,7 +36,7 @@ repos:
           )$
 
   - repo: https://github.com/igorshubovych/markdownlint-cli
-    rev: v0.44.0
+    rev: v0.43.0
     hooks:
       - id: markdownlint-fix
         exclude: |
@@ -57,10 +56,10 @@ repos:
             .*?invalid(_.+)*_syntax\.md
           )$
         additional_dependencies:
-          - black==25.1.0
+          - black==24.10.0
 
   - repo: https://github.com/crate-ci/typos
-    rev: v1.30.0
+    rev: v1.29.4
     hooks:
       - id: typos
 
@@ -74,7 +73,7 @@ repos:
         pass_filenames: false # This makes it a lot faster
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.9.9
+    rev: v0.9.2
     hooks:
       - id: ruff-format
       - id: ruff
@@ -84,7 +83,7 @@ repos:
 
   # Prettier
   - repo: https://github.com/rbubley/mirrors-prettier
-    rev: v3.5.2
+    rev: v3.4.2
     hooks:
       - id: prettier
         types: [yaml]
@@ -92,12 +91,12 @@ repos:
   # zizmor detects security vulnerabilities in GitHub Actions workflows.
   # Additional configuration for the tool is found in `.github/zizmor.yml`
   - repo: https://github.com/woodruffw/zizmor-pre-commit
-    rev: v1.4.1
+    rev: v1.2.2
     hooks:
       - id: zizmor
 
   - repo: https://github.com/python-jsonschema/check-jsonschema
-    rev: 0.31.2
+    rev: 0.31.0
     hooks:
       - id: check-github-workflows
 

BREAKING_CHANGES.md

@@ -209,8 +209,8 @@ This change only affects those using Ruff under its default rule set. Users that
 
 ### Remove support for emoji identifiers ([#7212](https://github.com/astral-sh/ruff/pull/7212))
 
-Previously, Ruff supported non-standards-compliant emoji identifiers such as `📦 = 1`.
-We decided to remove this non-standard language extension. Ruff now reports syntax errors for invalid emoji identifiers in your code, the same as CPython.
+Previously, Ruff supported the non-standard compliant emoji identifiers e.g. `📦 = 1`.
+We decided to remove this non-standard language extension, and Ruff now reports syntax errors for emoji identifiers in your code, the same as CPython.
 
 ### Improved GitLab fingerprints ([#7203](https://github.com/astral-sh/ruff/pull/7203))
 

CHANGELOG.md

@@ -1,269 +1,5 @@
 # Changelog
 
-## 0.9.10
-
-### Preview features
-
-- \[`ruff`\] Add new rule `RUF059`: Unused unpacked assignment ([#16449](https://github.com/astral-sh/ruff/pull/16449))
-- \[`syntax-errors`\] Detect assignment expressions before Python 3.8 ([#16383](https://github.com/astral-sh/ruff/pull/16383))
-- \[`syntax-errors`\] Named expressions in decorators before Python 3.9 ([#16386](https://github.com/astral-sh/ruff/pull/16386))
-- \[`syntax-errors`\] Parenthesized keyword argument names after Python 3.8 ([#16482](https://github.com/astral-sh/ruff/pull/16482))
-- \[`syntax-errors`\] Positional-only parameters before Python 3.8 ([#16481](https://github.com/astral-sh/ruff/pull/16481))
-- \[`syntax-errors`\] Tuple unpacking in `return` and `yield` before Python 3.8 ([#16485](https://github.com/astral-sh/ruff/pull/16485))
-- \[`syntax-errors`\] Type parameter defaults before Python 3.13 ([#16447](https://github.com/astral-sh/ruff/pull/16447))
-- \[`syntax-errors`\] Type parameter lists before Python 3.12 ([#16479](https://github.com/astral-sh/ruff/pull/16479))
-- \[`syntax-errors`\] `except*` before Python 3.11 ([#16446](https://github.com/astral-sh/ruff/pull/16446))
-- \[`syntax-errors`\] `type` statements before Python 3.12 ([#16478](https://github.com/astral-sh/ruff/pull/16478))
-
-### Bug fixes
-
-- Escape template filenames in glob patterns in configuration ([#16407](https://github.com/astral-sh/ruff/pull/16407))
-- \[`flake8-simplify`\] Exempt unittest context methods for `SIM115` rule ([#16439](https://github.com/astral-sh/ruff/pull/16439))
-- Formatter: Fix syntax error location in notebooks ([#16499](https://github.com/astral-sh/ruff/pull/16499))
-- \[`pyupgrade`\] Do not offer fix when at least one target is `global`/`nonlocal` (`UP028`) ([#16451](https://github.com/astral-sh/ruff/pull/16451))
-- \[`flake8-builtins`\] Ignore variables matching module attribute names (`A001`) ([#16454](https://github.com/astral-sh/ruff/pull/16454))
-- \[`pylint`\] Convert `code` keyword argument to a positional argument in fix for (`PLR1722`) ([#16424](https://github.com/astral-sh/ruff/pull/16424))
-
-### CLI
-
-- Move rule code from `description` to `check_name` in GitLab output serializer ([#16437](https://github.com/astral-sh/ruff/pull/16437))
-
-### Documentation
-
-- \[`pydocstyle`\] Clarify that `D417` only checks docstrings with an arguments section ([#16494](https://github.com/astral-sh/ruff/pull/16494))
-
-## 0.9.9
-
-### Preview features
-
-- Fix caching of unsupported-syntax errors ([#16425](https://github.com/astral-sh/ruff/pull/16425))
-
-### Bug fixes
-
-- Only show unsupported-syntax errors in editors when preview mode is enabled ([#16429](https://github.com/astral-sh/ruff/pull/16429))
-
-## 0.9.8
-
-### Preview features
-
-- Start detecting version-related syntax errors in the parser ([#16090](https://github.com/astral-sh/ruff/pull/16090))
-
-### Rule changes
-
-- \[`pylint`\] Mark fix unsafe (`PLW1507`) ([#16343](https://github.com/astral-sh/ruff/pull/16343))
-- \[`pylint`\] Catch `case np.nan`/`case math.nan` in `match` statements (`PLW0177`) ([#16378](https://github.com/astral-sh/ruff/pull/16378))
-- \[`ruff`\] Add more Pydantic models variants to the list of default copy semantics (`RUF012`) ([#16291](https://github.com/astral-sh/ruff/pull/16291))
-
-### Server
-
-- Avoid indexing the project if `configurationPreference` is `editorOnly` ([#16381](https://github.com/astral-sh/ruff/pull/16381))
-- Avoid unnecessary info at non-trace server log level ([#16389](https://github.com/astral-sh/ruff/pull/16389))
-- Expand `ruff.configuration` to allow inline config ([#16296](https://github.com/astral-sh/ruff/pull/16296))
-- Notify users for invalid client settings ([#16361](https://github.com/astral-sh/ruff/pull/16361))
-
-### Configuration
-
-- Add `per-file-target-version` option ([#16257](https://github.com/astral-sh/ruff/pull/16257))
-
-### Bug fixes
-
-- \[`refurb`\] Do not consider docstring(s) (`FURB156`) ([#16391](https://github.com/astral-sh/ruff/pull/16391))
-- \[`flake8-self`\] Ignore attribute accesses on instance-like variables (`SLF001`) ([#16149](https://github.com/astral-sh/ruff/pull/16149))
-- \[`pylint`\] Fix false positives, add missing methods, and support positional-only parameters (`PLE0302`) ([#16263](https://github.com/astral-sh/ruff/pull/16263))
-- \[`flake8-pyi`\] Mark `PYI030` fix unsafe when comments are deleted ([#16322](https://github.com/astral-sh/ruff/pull/16322))
-
-### Documentation
-
-- Fix example for `S611` ([#16316](https://github.com/astral-sh/ruff/pull/16316))
-- Normalize inconsistent markdown headings in docstrings ([#16364](https://github.com/astral-sh/ruff/pull/16364))
-- Document MSRV policy ([#16384](https://github.com/astral-sh/ruff/pull/16384))
-
-## 0.9.7
-
-### Preview features
-
-- Consider `__new__` methods as special function type for enforcing class method or static method rules ([#13305](https://github.com/astral-sh/ruff/pull/13305))
-- \[`airflow`\] Improve the internal logic to differentiate deprecated symbols (`AIR303`) ([#16013](https://github.com/astral-sh/ruff/pull/16013))
-- \[`refurb`\] Manual timezone monkeypatching (`FURB162`) ([#16113](https://github.com/astral-sh/ruff/pull/16113))
-- \[`ruff`\] Implicit class variable in dataclass (`RUF045`) ([#14349](https://github.com/astral-sh/ruff/pull/14349))
-- \[`ruff`\] Skip singleton starred expressions for `incorrectly-parenthesized-tuple-in-subscript` (`RUF031`) ([#16083](https://github.com/astral-sh/ruff/pull/16083))
-- \[`refurb`\] Check for subclasses includes subscript expressions (`FURB189`) ([#16155](https://github.com/astral-sh/ruff/pull/16155))
-
-### Rule changes
-
-- \[`flake8-debugger`\] Also flag `sys.breakpointhook` and `sys.__breakpointhook__` (`T100`) ([#16191](https://github.com/astral-sh/ruff/pull/16191))
-- \[`pycodestyle`\] Exempt `site.addsitedir(...)` calls (`E402`) ([#16251](https://github.com/astral-sh/ruff/pull/16251))
-
-### Formatter
-
-- Fix unstable formatting of trailing end-of-line comments of parenthesized attribute values ([#16187](https://github.com/astral-sh/ruff/pull/16187))
-
-### Server
-
-- Fix handling of requests received after shutdown message ([#16262](https://github.com/astral-sh/ruff/pull/16262))
-- Ignore `source.organizeImports.ruff` and `source.fixAll.ruff` code actions for a notebook cell ([#16154](https://github.com/astral-sh/ruff/pull/16154))
-- Include document specific debug info for `ruff.printDebugInformation` ([#16215](https://github.com/astral-sh/ruff/pull/16215))
-- Update server to return the debug info as string with `ruff.printDebugInformation` ([#16214](https://github.com/astral-sh/ruff/pull/16214))
-
-### CLI
-
-- Warn on invalid `noqa` even when there are no diagnostics ([#16178](https://github.com/astral-sh/ruff/pull/16178))
-- Better error messages while loading configuration `extend`s ([#15658](https://github.com/astral-sh/ruff/pull/15658))
-
-### Bug fixes
-
-- \[`flake8-comprehensions`\] Handle trailing comma in `C403` fix ([#16110](https://github.com/astral-sh/ruff/pull/16110))
-- \[`flake8-pyi`\] Avoid flagging `custom-typevar-for-self` on metaclass methods (`PYI019`) ([#16141](https://github.com/astral-sh/ruff/pull/16141))
-- \[`pydocstyle`\] Handle arguments with the same names as sections (`D417`) ([#16011](https://github.com/astral-sh/ruff/pull/16011))
-- \[`pylint`\] Correct ordering of arguments in fix for `if-stmt-min-max` (`PLR1730`) ([#16080](https://github.com/astral-sh/ruff/pull/16080))
-- \[`pylint`\] Do not offer fix for raw strings (`PLE251`) ([#16132](https://github.com/astral-sh/ruff/pull/16132))
-- \[`pyupgrade`\] Do not upgrade functional `TypedDicts` with private field names to the class-based syntax (`UP013`) ([#16219](https://github.com/astral-sh/ruff/pull/16219))
-- \[`pyupgrade`\] Handle micro version numbers correctly (`UP036`) ([#16091](https://github.com/astral-sh/ruff/pull/16091))
-- \[`pyupgrade`\] Unwrap unary expressions correctly (`UP018`) ([#15919](https://github.com/astral-sh/ruff/pull/15919))
-- \[`refurb`\] Correctly handle lengths of literal strings in `slice-to-remove-prefix-or-suffix` (`FURB188`) ([#16237](https://github.com/astral-sh/ruff/pull/16237))
-- \[`ruff`\] Skip `RUF001` diagnostics when visiting string type definitions ([#16122](https://github.com/astral-sh/ruff/pull/16122))
-
-### Documentation
-
-- Add FAQ entry for `source.*` code actions in Notebook ([#16212](https://github.com/astral-sh/ruff/pull/16212))
-- Add `SECURITY.md` ([#16224](https://github.com/astral-sh/ruff/pull/16224))
-
-## 0.9.6
-
-### Preview features
-
-- \[`airflow`\] Add `external_task.{ExternalTaskMarker, ExternalTaskSensor}` for `AIR302` ([#16014](https://github.com/astral-sh/ruff/pull/16014))
-- \[`flake8-builtins`\] Make strict module name comparison optional (`A005`) ([#15951](https://github.com/astral-sh/ruff/pull/15951))
-- \[`flake8-pyi`\] Extend fix to Python \<= 3.9 for `redundant-none-literal` (`PYI061`) ([#16044](https://github.com/astral-sh/ruff/pull/16044))
-- \[`pylint`\] Also report when the object isn't a literal (`PLE1310`) ([#15985](https://github.com/astral-sh/ruff/pull/15985))
-- \[`ruff`\] Implement `indented-form-feed` (`RUF054`) ([#16049](https://github.com/astral-sh/ruff/pull/16049))
-- \[`ruff`\] Skip type definitions for `missing-f-string-syntax` (`RUF027`) ([#16054](https://github.com/astral-sh/ruff/pull/16054))
-
-### Rule changes
-
-- \[`flake8-annotations`\] Correct syntax for `typing.Union` in suggested return type fixes for `ANN20x` rules ([#16025](https://github.com/astral-sh/ruff/pull/16025))
-- \[`flake8-builtins`\] Match upstream module name comparison (`A005`) ([#16006](https://github.com/astral-sh/ruff/pull/16006))
-- \[`flake8-comprehensions`\] Detect overshadowed `list`/`set`/`dict`, ignore variadics and named expressions (`C417`) ([#15955](https://github.com/astral-sh/ruff/pull/15955))
-- \[`flake8-pie`\] Remove following comma correctly when the unpacked dictionary is empty (`PIE800`) ([#16008](https://github.com/astral-sh/ruff/pull/16008))
-- \[`flake8-simplify`\] Only trigger `SIM401` on known dictionaries ([#15995](https://github.com/astral-sh/ruff/pull/15995))
-- \[`pylint`\] Do not report calls when object type and argument type mismatch, remove custom escape handling logic (`PLE1310`) ([#15984](https://github.com/astral-sh/ruff/pull/15984))
-- \[`pyupgrade`\] Comments within parenthesized value ranges should not affect applicability (`UP040`) ([#16027](https://github.com/astral-sh/ruff/pull/16027))
-- \[`pyupgrade`\] Don't introduce invalid syntax when upgrading old-style type aliases with parenthesized multiline values (`UP040`) ([#16026](https://github.com/astral-sh/ruff/pull/16026))
-- \[`pyupgrade`\] Ensure we do not rename two type parameters to the same name (`UP049`) ([#16038](https://github.com/astral-sh/ruff/pull/16038))
-- \[`pyupgrade`\] \[`ruff`\] Don't apply renamings if the new name is shadowed in a scope of one of the references to the binding (`UP049`, `RUF052`) ([#16032](https://github.com/astral-sh/ruff/pull/16032))
-- \[`ruff`\] Update `RUF009` to behave similar to `B008` and ignore attributes with immutable types ([#16048](https://github.com/astral-sh/ruff/pull/16048))
-
-### Server
-
-- Root exclusions in the server to project root ([#16043](https://github.com/astral-sh/ruff/pull/16043))
-
-### Bug fixes
-
-- \[`flake8-datetime`\] Ignore `.replace()` calls while looking for `.astimezone` ([#16050](https://github.com/astral-sh/ruff/pull/16050))
-- \[`flake8-type-checking`\] Avoid `TC004` false positive where the runtime definition is provided by `__getattr__` ([#16052](https://github.com/astral-sh/ruff/pull/16052))
-
-### Documentation
-
-- Improve `ruff-lsp` migration document ([#16072](https://github.com/astral-sh/ruff/pull/16072))
-- Undeprecate `ruff.nativeServer` ([#16039](https://github.com/astral-sh/ruff/pull/16039))
-
-## 0.9.5
-
-### Preview features
-
-- Recognize all symbols named `TYPE_CHECKING` for `in_type_checking_block` ([#15719](https://github.com/astral-sh/ruff/pull/15719))
-- \[`flake8-comprehensions`\] Handle builtins at top of file correctly for `unnecessary-dict-comprehension-for-iterable` (`C420`) ([#15837](https://github.com/astral-sh/ruff/pull/15837))
-- \[`flake8-logging`\] `.exception()` and `exc_info=` outside exception handlers (`LOG004`, `LOG014`) ([#15799](https://github.com/astral-sh/ruff/pull/15799))
-- \[`flake8-pyi`\] Fix incorrect behaviour of `custom-typevar-return-type` preview-mode autofix if `typing` was already imported (`PYI019`) ([#15853](https://github.com/astral-sh/ruff/pull/15853))
-- \[`flake8-pyi`\] Fix more complex cases (`PYI019`) ([#15821](https://github.com/astral-sh/ruff/pull/15821))
-- \[`flake8-pyi`\] Make `PYI019` autofixable for `.py` files in preview mode as well as stubs ([#15889](https://github.com/astral-sh/ruff/pull/15889))
-- \[`flake8-pyi`\] Remove type parameter correctly when it is the last (`PYI019`) ([#15854](https://github.com/astral-sh/ruff/pull/15854))
-- \[`pylint`\] Fix missing parens in unsafe fix for `unnecessary-dunder-call` (`PLC2801`) ([#15762](https://github.com/astral-sh/ruff/pull/15762))
-- \[`pyupgrade`\] Better messages and diagnostic range (`UP015`) ([#15872](https://github.com/astral-sh/ruff/pull/15872))
-- \[`pyupgrade`\] Rename private type parameters in PEP 695 generics (`UP049`) ([#15862](https://github.com/astral-sh/ruff/pull/15862))
-- \[`refurb`\] Also report non-name expressions (`FURB169`) ([#15905](https://github.com/astral-sh/ruff/pull/15905))
-- \[`refurb`\] Mark fix as unsafe if there are comments (`FURB171`) ([#15832](https://github.com/astral-sh/ruff/pull/15832))
-- \[`ruff`\] Classes with mixed type variable style (`RUF053`) ([#15841](https://github.com/astral-sh/ruff/pull/15841))
-- \[`airflow`\] `BashOperator` has been moved to `airflow.providers.standard.operators.bash.BashOperator` (`AIR302`) ([#15922](https://github.com/astral-sh/ruff/pull/15922))
-- \[`flake8-pyi`\] Add autofix for unused-private-type-var (`PYI018`) ([#15999](https://github.com/astral-sh/ruff/pull/15999))
-- \[`flake8-pyi`\] Significantly improve accuracy of `PYI019` if preview mode is enabled ([#15888](https://github.com/astral-sh/ruff/pull/15888))
-
-### Rule changes
-
-- Preserve triple quotes and prefixes for strings ([#15818](https://github.com/astral-sh/ruff/pull/15818))
-- \[`flake8-comprehensions`\] Skip when `TypeError` present from too many (kw)args for `C410`,`C411`, and `C418` ([#15838](https://github.com/astral-sh/ruff/pull/15838))
-- \[`flake8-pyi`\] Rename `PYI019` and improve its diagnostic message ([#15885](https://github.com/astral-sh/ruff/pull/15885))
-- \[`pep8-naming`\] Ignore `@override` methods (`N803`) ([#15954](https://github.com/astral-sh/ruff/pull/15954))
-- \[`pyupgrade`\] Reuse replacement logic from `UP046` and `UP047` to preserve more comments (`UP040`) ([#15840](https://github.com/astral-sh/ruff/pull/15840))
-- \[`ruff`\] Analyze deferred annotations before enforcing `mutable-(data)class-default` and `function-call-in-dataclass-default-argument` (`RUF008`,`RUF009`,`RUF012`) ([#15921](https://github.com/astral-sh/ruff/pull/15921))
-- \[`pycodestyle`\] Exempt `sys.path += ...` calls (`E402`) ([#15980](https://github.com/astral-sh/ruff/pull/15980))
-
-### Configuration
-
-- Config error only when `flake8-import-conventions` alias conflicts with `isort.required-imports` bound name ([#15918](https://github.com/astral-sh/ruff/pull/15918))
-- Workaround Even Better TOML crash related to `allOf` ([#15992](https://github.com/astral-sh/ruff/pull/15992))
-
-### Bug fixes
-
-- \[`flake8-comprehensions`\] Unnecessary `list` comprehension (rewrite as a `set` comprehension) (`C403`) - Handle extraneous parentheses around list comprehension ([#15877](https://github.com/astral-sh/ruff/pull/15877))
-- \[`flake8-comprehensions`\] Handle trailing comma in fixes for `unnecessary-generator-list/set` (`C400`,`C401`) ([#15929](https://github.com/astral-sh/ruff/pull/15929))
-- \[`flake8-pyi`\] Fix several correctness issues with `custom-type-var-return-type` (`PYI019`) ([#15851](https://github.com/astral-sh/ruff/pull/15851))
-- \[`pep8-naming`\] Consider any number of leading underscore for `N801` ([#15988](https://github.com/astral-sh/ruff/pull/15988))
-- \[`pyflakes`\] Visit forward annotations in `TypeAliasType` as types (`F401`) ([#15829](https://github.com/astral-sh/ruff/pull/15829))
-- \[`pylint`\] Correct min/max auto-fix and suggestion for (`PL1730`) ([#15930](https://github.com/astral-sh/ruff/pull/15930))
-- \[`refurb`\] Handle unparenthesized tuples correctly (`FURB122`, `FURB142`) ([#15953](https://github.com/astral-sh/ruff/pull/15953))
-- \[`refurb`\] Avoid `None | None` as well as better detection and fix (`FURB168`) ([#15779](https://github.com/astral-sh/ruff/pull/15779))
-
-### Documentation
-
-- Add deprecation warning for `ruff-lsp` related settings ([#15850](https://github.com/astral-sh/ruff/pull/15850))
-- Docs (`linter.md`): clarify that Python files are always searched for in subdirectories ([#15882](https://github.com/astral-sh/ruff/pull/15882))
-- Fix a typo in `non_pep695_generic_class.rs` ([#15946](https://github.com/astral-sh/ruff/pull/15946))
-- Improve Docs: Pylint subcategories' codes ([#15909](https://github.com/astral-sh/ruff/pull/15909))
-- Remove non-existing `lint.extendIgnore` editor setting ([#15844](https://github.com/astral-sh/ruff/pull/15844))
-- Update black deviations ([#15928](https://github.com/astral-sh/ruff/pull/15928))
-- Mention `UP049` in `UP046` and `UP047`, add `See also` section to `UP040` ([#15956](https://github.com/astral-sh/ruff/pull/15956))
-- Add instance variable examples to `RUF012` ([#15982](https://github.com/astral-sh/ruff/pull/15982))
-- Explain precedence for `ignore` and `select` config ([#15883](https://github.com/astral-sh/ruff/pull/15883))
-
-## 0.9.4
-
-### Preview features
-
-- \[`airflow`\] Extend airflow context parameter check for `BaseOperator.execute` (`AIR302`) ([#15713](https://github.com/astral-sh/ruff/pull/15713))
-- \[`airflow`\] Update `AIR302` to check for deprecated context keys ([#15144](https://github.com/astral-sh/ruff/pull/15144))
-- \[`flake8-bandit`\] Permit suspicious imports within stub files (`S4`) ([#15822](https://github.com/astral-sh/ruff/pull/15822))
-- \[`pylint`\] Do not trigger `PLR6201` on empty collections ([#15732](https://github.com/astral-sh/ruff/pull/15732))
-- \[`refurb`\] Do not emit diagnostic when loop variables are used outside loop body (`FURB122`) ([#15757](https://github.com/astral-sh/ruff/pull/15757))
-- \[`ruff`\] Add support for more `re` patterns (`RUF055`) ([#15764](https://github.com/astral-sh/ruff/pull/15764))
-- \[`ruff`\] Check for shadowed `map` before suggesting fix (`RUF058`) ([#15790](https://github.com/astral-sh/ruff/pull/15790))
-- \[`ruff`\] Do not emit diagnostic when all arguments to `zip()` are variadic (`RUF058`) ([#15744](https://github.com/astral-sh/ruff/pull/15744))
-- \[`ruff`\] Parenthesize fix when argument spans multiple lines for `unnecessary-round` (`RUF057`) ([#15703](https://github.com/astral-sh/ruff/pull/15703))
-
-### Rule changes
-
-- Preserve quote style in generated code ([#15726](https://github.com/astral-sh/ruff/pull/15726), [#15778](https://github.com/astral-sh/ruff/pull/15778), [#15794](https://github.com/astral-sh/ruff/pull/15794))
-- \[`flake8-bugbear`\] Exempt `NewType` calls where the original type is immutable (`B008`) ([#15765](https://github.com/astral-sh/ruff/pull/15765))
-- \[`pylint`\] Honor banned top-level imports by `TID253` in `PLC0415`. ([#15628](https://github.com/astral-sh/ruff/pull/15628))
-- \[`pyupgrade`\] Ignore `is_typeddict` and `TypedDict` for `deprecated-import` (`UP035`) ([#15800](https://github.com/astral-sh/ruff/pull/15800))
-
-### CLI
-
-- Fix formatter warning message for `flake8-quotes` option ([#15788](https://github.com/astral-sh/ruff/pull/15788))
-- Implement tab autocomplete for `ruff config` ([#15603](https://github.com/astral-sh/ruff/pull/15603))
-
-### Bug fixes
-
-- \[`flake8-comprehensions`\] Do not emit `unnecessary-map` diagnostic when lambda has different arity (`C417`) ([#15802](https://github.com/astral-sh/ruff/pull/15802))
-- \[`flake8-comprehensions`\] Parenthesize `sorted` when needed for `unnecessary-call-around-sorted` (`C413`) ([#15825](https://github.com/astral-sh/ruff/pull/15825))
-- \[`pyupgrade`\] Handle end-of-line comments for `quoted-annotation` (`UP037`) ([#15824](https://github.com/astral-sh/ruff/pull/15824))
-
-### Documentation
-
-- Add missing config docstrings ([#15803](https://github.com/astral-sh/ruff/pull/15803))
-- Add references to `trio.run_process` and `anyio.run_process` ([#15761](https://github.com/astral-sh/ruff/pull/15761))
-- Use `uv init --lib` in tutorial ([#15718](https://github.com/astral-sh/ruff/pull/15718))
-
 ## 0.9.3
 
 ### Preview features

CONTRIBUTING.md

@@ -526,7 +526,7 @@ cargo benchmark
 #### Benchmark-driven Development
 
 Ruff uses [Criterion.rs](https://bheisler.github.io/criterion.rs/book/) for benchmarks. You can use
-`--save-baseline=<name>` to store an initial baseline benchmark (e.g., on `main`) and then use
+`--save-baseline=<name>` to store an initial baseline benchmark (e.g. on `main`) and then use
 `--benchmark=<name>` to compare against that benchmark. Criterion will print a message telling you
 if the benchmark improved/regressed compared to that baseline.
 
@@ -678,9 +678,9 @@ utils with it:
 23 Newline 24
 ```
 
-- `cargo dev print-cst <file>`: Print the CST of a Python file using
+- `cargo dev print-cst <file>`: Print the CST of a python file using
     [LibCST](https://github.com/Instagram/LibCST), which is used in addition to the RustPython parser
-    in Ruff. For example, for `if True: pass # comment`, everything, including the whitespace, is represented:
+    in Ruff. E.g. for `if True: pass # comment` everything including the whitespace is represented:
 
 ```text
 Module {

Cargo.toml

@@ -4,7 +4,7 @@ resolver = "2"
 
 [workspace.package]
 edition = "2021"
-rust-version = "1.83"
+rust-version = "1.80"
 homepage = "https://docs.astral.sh/ruff"
 documentation = "https://docs.astral.sh/ruff"
 repository = "https://github.com/astral-sh/ruff"
@@ -74,13 +74,11 @@ env_logger = { version = "0.11.0" }
 etcetera = { version = "0.8.0" }
 fern = { version = "0.7.0" }
 filetime = { version = "0.2.23" }
-getrandom = { version = "0.3.1" }
 glob = { version = "0.3.1" }
 globset = { version = "0.4.14" }
 globwalk = { version = "0.9.1" }
 hashbrown = { version = "0.15.0", default-features = false, features = [
     "raw-entry",
-    "equivalent",
     "inline-more",
 ] }
 ignore = { version = "0.4.22" }
@@ -118,12 +116,12 @@ proc-macro2 = { version = "1.0.79" }
 pyproject-toml = { version = "0.13.4" }
 quick-junit = { version = "0.5.0" }
 quote = { version = "1.0.23" }
-rand = { version = "0.9.0" }
+rand = { version = "0.8.5" }
 rayon = { version = "1.10.0" }
 regex = { version = "1.10.2" }
 rustc-hash = { version = "2.0.0" }
 # When updating salsa, make sure to also update the revision in `fuzz/Cargo.toml`
-salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "99be5d9917c3dd88e19735a82ef6bf39ba84bd7e" }
+salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "88a1d7774d78f048fbd77d40abca9ebd729fd1f0" }
 schemars = { version = "0.8.16" }
 seahash = { version = "4.1.0" }
 serde = { version = "1.0.197", features = ["derive"] }
@@ -136,15 +134,10 @@ serde_with = { version = "3.6.0", default-features = false, features = [
 shellexpand = { version = "3.0.0" }
 similar = { version = "2.4.0", features = ["inline"] }
 smallvec = { version = "1.13.2" }
-snapbox = { version = "0.6.0", features = [
-    "diff",
-    "term-svg",
-    "cmd",
-    "examples",
-] }
+snapbox = { version = "0.6.0", features = ["diff", "term-svg", "cmd", "examples"] }
 static_assertions = "1.1.0"
-strum = { version = "0.27.0", features = ["strum_macros"] }
-strum_macros = { version = "0.27.0" }
+strum = { version = "0.26.0", features = ["strum_macros"] }
+strum_macros = { version = "0.26.0" }
 syn = { version = "2.0.55" }
 tempfile = { version = "3.9.0" }
 test-case = { version = "3.3.1" }
@@ -166,6 +159,7 @@ unicode-ident = { version = "1.0.12" }
 unicode-width = { version = "0.2.0" }
 unicode_names2 = { version = "1.2.2" }
 unicode-normalization = { version = "0.1.23" }
+ureq = { version = "2.9.6" }
 url = { version = "2.5.0" }
 uuid = { version = "1.6.1", features = [
     "v4",
@@ -179,10 +173,6 @@ wasm-bindgen-test = { version = "0.3.42" }
 wild = { version = "2" }
 zip = { version = "0.6.6", default-features = false }
 
-[workspace.metadata.cargo-shear]
-ignored = ["getrandom"]
-
-
 [workspace.lints.rust]
 unsafe_code = "warn"
 unreachable_pub = "warn"
@@ -315,11 +305,7 @@ local-artifacts-jobs = ["./build-binaries", "./build-docker"]
 # Publish jobs to run in CI
 publish-jobs = ["./publish-pypi", "./publish-wasm"]
 # Post-announce jobs to run in CI
-post-announce-jobs = [
-    "./notify-dependents",
-    "./publish-docs",
-    "./publish-playground",
-]
+post-announce-jobs = ["./notify-dependents", "./publish-docs", "./publish-playground"]
 # Custom permissions for GitHub Jobs
 github-custom-job-permissions = { "build-docker" = { packages = "write", contents = "read" }, "publish-wasm" = { contents = "read", id-token = "write", packages = "write" } }
 # Whether to install an updater program

README.md

@@ -149,8 +149,8 @@ curl -LsSf https://astral.sh/ruff/install.sh | sh
 powershell -c "irm https://astral.sh/ruff/install.ps1 | iex"
 
 # For a specific version.
-curl -LsSf https://astral.sh/ruff/0.9.10/install.sh | sh
-powershell -c "irm https://astral.sh/ruff/0.9.10/install.ps1 | iex"
+curl -LsSf https://astral.sh/ruff/0.9.3/install.sh | sh
+powershell -c "irm https://astral.sh/ruff/0.9.3/install.ps1 | iex"
 ```
 
 You can also install Ruff via [Homebrew](https://formulae.brew.sh/formula/ruff), [Conda](https://anaconda.org/conda-forge/ruff),
@@ -183,7 +183,7 @@ Ruff can also be used as a [pre-commit](https://pre-commit.com/) hook via [`ruff
 ```yaml
 - repo: https://github.com/astral-sh/ruff-pre-commit
   # Ruff version.
-  rev: v0.9.10
+  rev: v0.9.3
   hooks:
     # Run the linter.
     - id: ruff
@@ -452,7 +452,6 @@ Ruff is used by a number of major open-source projects and companies, including:
 - ING Bank ([popmon](https://github.com/ing-bank/popmon), [probatus](https://github.com/ing-bank/probatus))
 - [Ibis](https://github.com/ibis-project/ibis)
 - [ivy](https://github.com/unifyai/ivy)
-- [JAX](https://github.com/jax-ml/jax)
 - [Jupyter](https://github.com/jupyter-server/jupyter_server)
 - [Kraken Tech](https://kraken.tech/)
 - [LangChain](https://github.com/hwchase17/langchain)

SECURITY.md

@@ -1,15 +0,0 @@
-# Security policy
-
-## Reporting a vulnerability
-
-If you have found a possible vulnerability, please email `security at astral dot sh`.
-
-## Bug bounties
-
-While we sincerely appreciate and encourage reports of suspected security problems, please note that
-Astral does not currently run any bug bounty programs.
-
-## Vulnerability disclosures
-
-Critical vulnerabilities will be disclosed via GitHub's
-[security advisory](https://github.com/astral-sh/ruff/security) system.

_typos.toml

@@ -23,10 +23,6 @@ extend-ignore-re = [
     # Line ignore with trailing "spellchecker:disable-line"
     "(?Rm)^.*#\\s*spellchecker:disable-line$",
     "LICENSEs",
-    # Various third party dependencies uses `typ` as struct field names (e.g., lsp_types::LogMessageParams)
-    "typ",
-    # TODO: Remove this once the `TYP` redirects are removed from `rule_redirects.rs`
-    "TYP",
 ]
 
 [default.extend-identifiers]

crates/red_knot/Cargo.toml

@@ -16,10 +16,8 @@ red_knot_python_semantic = { workspace = true }
 red_knot_project = { workspace = true, features = ["zstd"] }
 red_knot_server = { workspace = true }
 ruff_db = { workspace = true, features = ["os", "cache"] }
-ruff_python_ast = { workspace = true }
 
 anyhow = { workspace = true }
-argfile = { workspace = true }
 chrono = { workspace = true }
 clap = { workspace = true, features = ["wrap_help"] }
 colored = { workspace = true }
@@ -32,7 +30,6 @@ tracing = { workspace = true, features = ["release_max_level_debug"] }
 tracing-subscriber = { workspace = true, features = ["env-filter", "fmt"] }
 tracing-flame = { workspace = true }
 tracing-tree = { workspace = true }
-wild = { workspace = true }
 
 [dev-dependencies]
 ruff_db = { workspace = true, features = ["testing"] }

crates/red_knot/README.md

@@ -1,25 +0,0 @@
-# Red Knot
-
-Red Knot is an extremely fast type checker.
-Currently, it is a work-in-progress and not ready for user testing.
-
-Red Knot is designed to prioritize good type inference, even in unannotated code,
-and aims to avoid false positives.
-
-While Red Knot will produce similar results to mypy and pyright on many codebases,
-100% compatibility with these tools is a non-goal.
-On some codebases, Red Knot's design decisions lead to different outcomes
-than you would get from running one of these more established tools.
-
-## Contributing
-
-Core type checking tests are written as Markdown code blocks.
-They can be found in [`red_knot_python_semantic/resources/mdtest`][resources-mdtest].
-See [`red_knot_test/README.md`][mdtest-readme] for more information
-on the test framework itself.
-
-The list of open issues can be found [here][open-issues].
-
-[mdtest-readme]: ../red_knot_test/README.md
-[open-issues]: https://github.com/astral-sh/ruff/issues?q=sort%3Aupdated-desc%20is%3Aissue%20is%3Aopen%20label%3Ared-knot
-[resources-mdtest]: ../red_knot_python_semantic/resources/mdtest

crates/red_knot/build.rs

@@ -1,104 +0,0 @@
-use std::{
-    fs,
-    path::{Path, PathBuf},
-    process::Command,
-};
-
-fn main() {
-    // The workspace root directory is not available without walking up the tree
-    // https://github.com/rust-lang/cargo/issues/3946
-    let workspace_root = Path::new(&std::env::var("CARGO_MANIFEST_DIR").unwrap())
-        .join("..")
-        .join("..");
-
-    commit_info(&workspace_root);
-
-    #[allow(clippy::disallowed_methods)]
-    let target = std::env::var("TARGET").unwrap();
-    println!("cargo::rustc-env=RUST_HOST_TARGET={target}");
-}
-
-fn commit_info(workspace_root: &Path) {
-    // If not in a git repository, do not attempt to retrieve commit information
-    let git_dir = workspace_root.join(".git");
-    if !git_dir.exists() {
-        return;
-    }
-
-    if let Some(git_head_path) = git_head(&git_dir) {
-        println!("cargo:rerun-if-changed={}", git_head_path.display());
-
-        let git_head_contents = fs::read_to_string(git_head_path);
-        if let Ok(git_head_contents) = git_head_contents {
-            // The contents are either a commit or a reference in the following formats
-            // - "<commit>" when the head is detached
-            // - "ref <ref>" when working on a branch
-            // If a commit, checking if the HEAD file has changed is sufficient
-            // If a ref, we need to add the head file for that ref to rebuild on commit
-            let mut git_ref_parts = git_head_contents.split_whitespace();
-            git_ref_parts.next();
-            if let Some(git_ref) = git_ref_parts.next() {
-                let git_ref_path = git_dir.join(git_ref);
-                println!("cargo:rerun-if-changed={}", git_ref_path.display());
-            }
-        }
-    }
-
-    let output = match Command::new("git")
-        .arg("log")
-        .arg("-1")
-        .arg("--date=short")
-        .arg("--abbrev=9")
-        .arg("--format=%H %h %cd %(describe)")
-        .output()
-    {
-        Ok(output) if output.status.success() => output,
-        _ => return,
-    };
-    let stdout = String::from_utf8(output.stdout).unwrap();
-    let mut parts = stdout.split_whitespace();
-    let mut next = || parts.next().unwrap();
-    let _commit_hash = next();
-    println!("cargo::rustc-env=RED_KNOT_COMMIT_SHORT_HASH={}", next());
-    println!("cargo::rustc-env=RED_KNOT_COMMIT_DATE={}", next());
-
-    // Describe can fail for some commits
-    // https://git-scm.com/docs/pretty-formats#Documentation/pretty-formats.txt-emdescribeoptionsem
-    if let Some(describe) = parts.next() {
-        let mut describe_parts = describe.split('-');
-        let _last_tag = describe_parts.next().unwrap();
-
-        // If this is the tagged commit, this component will be missing
-        println!(
-            "cargo::rustc-env=RED_KNOT_LAST_TAG_DISTANCE={}",
-            describe_parts.next().unwrap_or("0")
-        );
-    }
-}
-
-fn git_head(git_dir: &Path) -> Option<PathBuf> {
-    // The typical case is a standard git repository.
-    let git_head_path = git_dir.join("HEAD");
-    if git_head_path.exists() {
-        return Some(git_head_path);
-    }
-    if !git_dir.is_file() {
-        return None;
-    }
-    // If `.git/HEAD` doesn't exist and `.git` is actually a file,
-    // then let's try to attempt to read it as a worktree. If it's
-    // a worktree, then its contents will look like this, e.g.:
-    //
-    //     gitdir: /home/andrew/astral/uv/main/.git/worktrees/pr2
-    //
-    // And the HEAD file we want to watch will be at:
-    //
-    //     /home/andrew/astral/uv/main/.git/worktrees/pr2/HEAD
-    let contents = fs::read_to_string(git_dir).ok()?;
-    let (label, worktree_path) = contents.split_once(':')?;
-    if label != "gitdir" {
-        return None;
-    }
-    let worktree_path = worktree_path.trim();
-    Some(PathBuf::from(worktree_path))
-}

crates/red_knot/src/args.rs

@@ -1,7 +1,7 @@
 use crate::logging::Verbosity;
 use crate::python_version::PythonVersion;
 use clap::{ArgAction, ArgMatches, Error, Parser};
-use red_knot_project::metadata::options::{EnvironmentOptions, Options, TerminalOptions};
+use red_knot_project::metadata::options::{EnvironmentOptions, Options};
 use red_knot_project::metadata::value::{RangedValue, RelativePathBuf};
 use red_knot_python_semantic::lint;
 use ruff_db::system::SystemPathBuf;
@@ -25,20 +25,10 @@ pub(crate) enum Command {
 
     /// Start the language server
     Server,
-
-    /// Display Red Knot's version
-    Version,
 }
 
 #[derive(Debug, Parser)]
 pub(crate) struct CheckCommand {
-    /// List of files or directories to check.
-    #[clap(
-        help = "List of files or directories to check [default: the project root]",
-        value_name = "PATH"
-    )]
-    pub paths: Vec<SystemPathBuf>,
-
     /// Run the command within the given project directory.
     ///
     /// All `pyproject.toml` files will be discovered by walking up the directory tree from the given project directory,
@@ -48,14 +38,12 @@ pub(crate) struct CheckCommand {
     #[arg(long, value_name = "PROJECT")]
     pub(crate) project: Option<SystemPathBuf>,
 
-    /// Path to the Python installation from which Red Knot resolves type information and third-party dependencies.
+    /// Path to the virtual environment the project uses.
     ///
-    /// Red Knot will search in the path's `site-packages` directories for type information and
-    /// third-party imports.
-    ///
-    /// This option is commonly used to specify the path to a virtual environment.
+    /// If provided, red-knot will use the `site-packages` directory of this virtual environment
+    /// to resolve type information for the project's third-party dependencies.
     #[arg(long, value_name = "PATH")]
-    pub(crate) python: Option<SystemPathBuf>,
+    pub(crate) venv_path: Option<SystemPathBuf>,
 
     /// Custom directory to use for stdlib typeshed stubs.
     #[arg(long, value_name = "PATH", alias = "custom-typeshed-dir")]
@@ -75,15 +63,7 @@ pub(crate) struct CheckCommand {
     #[clap(flatten)]
     pub(crate) rules: RulesArg,
 
-    /// Use exit code 1 if there are any warning-level diagnostics.
-    #[arg(long, conflicts_with = "exit_zero", default_missing_value = "true", num_args=0..1)]
-    pub(crate) error_on_warning: Option<bool>,
-
-    /// Always use exit code 0, even when there are error-level diagnostics.
-    #[arg(long)]
-    pub(crate) exit_zero: bool,
-
-    /// Watch files for changes and recheck files related to the changed files.
+    /// Run in watch mode by re-running whenever files change.
     #[arg(long, short = 'W')]
     pub(crate) watch: bool,
 }
@@ -106,7 +86,7 @@ impl CheckCommand {
                 python_version: self
                     .python_version
                     .map(|version| RangedValue::cli(version.into())),
-                python: self.python.map(RelativePathBuf::cli),
+                venv_path: self.venv_path.map(RelativePathBuf::cli),
                 typeshed: self.typeshed.map(RelativePathBuf::cli),
                 extra_paths: self.extra_search_path.map(|extra_search_paths| {
                     extra_search_paths
@@ -116,9 +96,6 @@ impl CheckCommand {
                 }),
                 ..EnvironmentOptions::default()
             }),
-            terminal: Some(TerminalOptions {
-                error_on_warning: self.error_on_warning,
-            }),
             rules,
             ..Default::default()
         }

crates/red_knot/src/main.rs

@@ -1,7 +1,4 @@
-use std::io::{self, stdout, BufWriter, Write};
 use std::process::{ExitCode, Termination};
-
-use anyhow::Result;
 use std::sync::Mutex;
 
 use crate::args::{Args, CheckCommand, Command};
@@ -11,18 +8,18 @@ use clap::Parser;
 use colored::Colorize;
 use crossbeam::channel as crossbeam_channel;
 use red_knot_project::metadata::options::Options;
+use red_knot_project::watch;
 use red_knot_project::watch::ProjectWatcher;
-use red_knot_project::{watch, Db};
 use red_knot_project::{ProjectDatabase, ProjectMetadata};
 use red_knot_server::run_server;
-use ruff_db::diagnostic::{DisplayDiagnosticConfig, OldDiagnosticTrait, Severity};
-use ruff_db::system::{OsSystem, SystemPath, SystemPathBuf};
+use ruff_db::diagnostic::Diagnostic;
+use ruff_db::system::{OsSystem, System, SystemPath, SystemPathBuf};
 use salsa::plumbing::ZalsaDatabase;
 
 mod args;
 mod logging;
 mod python_version;
-mod version;
+mod verbosity;
 
 #[allow(clippy::print_stdout, clippy::unnecessary_wraps, clippy::print_stderr)]
 pub fn main() -> ExitStatus {
@@ -39,15 +36,6 @@ pub fn main() -> ExitStatus {
         // the configuration it is help to chain errors ("resolving configuration failed" ->
         // "failed to read file: subdir/pyproject.toml")
         for cause in error.chain() {
-            // Exit "gracefully" on broken pipe errors.
-            //
-            // See: https://github.com/BurntSushi/ripgrep/blob/bf63fe8f258afc09bae6caa48f0ae35eaf115005/crates/core/main.rs#L47C1-L61C14
-            if let Some(ioerr) = cause.downcast_ref::<io::Error>() {
-                if ioerr.kind() == io::ErrorKind::BrokenPipe {
-                    return ExitStatus::Success;
-                }
-            }
-
             writeln!(stderr, "  {} {cause}", "Cause:".bold()).ok();
         }
 
@@ -56,32 +44,21 @@ pub fn main() -> ExitStatus {
 }
 
 fn run() -> anyhow::Result<ExitStatus> {
-    let args = wild::args_os();
-    let args = argfile::expand_args_from(args, argfile::parse_fromfile, argfile::PREFIX)
-        .context("Failed to read CLI arguments from file")?;
-    let args = Args::parse_from(args);
+    let args = Args::parse_from(std::env::args());
 
     match args.command {
         Command::Server => run_server().map(|()| ExitStatus::Success),
         Command::Check(check_args) => run_check(check_args),
-        Command::Version => version().map(|()| ExitStatus::Success),
     }
 }
 
-pub(crate) fn version() -> Result<()> {
-    let mut stdout = BufWriter::new(io::stdout().lock());
-    let version_info = crate::version::version();
-    writeln!(stdout, "red knot {}", &version_info)?;
-    Ok(())
-}
-
 fn run_check(args: CheckCommand) -> anyhow::Result<ExitStatus> {
     let verbosity = args.verbosity.level();
     countme::enable(verbosity.is_trace());
     let _guard = setup_tracing(verbosity)?;
 
     // The base path to which all CLI arguments are relative to.
-    let cwd = {
+    let cli_base_path = {
         let cwd = std::env::current_dir().context("Failed to get the current working directory")?;
         SystemPathBuf::from_path_buf(cwd)
             .map_err(|path| {
@@ -92,41 +69,26 @@ fn run_check(args: CheckCommand) -> anyhow::Result<ExitStatus> {
             })?
     };
 
-    let project_path = args
+    let cwd = args
         .project
         .as_ref()
-        .map(|project| {
-            if project.as_std_path().is_dir() {
-                Ok(SystemPath::absolute(project, &cwd))
+        .map(|cwd| {
+            if cwd.as_std_path().is_dir() {
+                Ok(SystemPath::absolute(cwd, &cli_base_path))
             } else {
-                Err(anyhow!(
-                    "Provided project path `{project}` is not a directory"
-                ))
+                Err(anyhow!("Provided project path `{cwd}` is not a directory"))
             }
         })
         .transpose()?
-        .unwrap_or_else(|| cwd.clone());
-
-    let check_paths: Vec<_> = args
-        .paths
-        .iter()
-        .map(|path| SystemPath::absolute(path, &cwd))
-        .collect();
+        .unwrap_or_else(|| cli_base_path.clone());
 
     let system = OsSystem::new(cwd);
     let watch = args.watch;
-    let exit_zero = args.exit_zero;
-
     let cli_options = args.into_options();
-    let mut project_metadata = ProjectMetadata::discover(&project_path, &system)?;
-    project_metadata.apply_cli_options(cli_options.clone());
-    project_metadata.apply_configuration_files(&system)?;
+    let mut workspace_metadata = ProjectMetadata::discover(system.current_directory(), &system)?;
+    workspace_metadata.apply_cli_options(cli_options.clone());
 
-    let mut db = ProjectDatabase::new(project_metadata, system)?;
-
-    if !check_paths.is_empty() {
-        db.project().set_included_paths(&mut db, check_paths);
-    }
+    let mut db = ProjectDatabase::new(workspace_metadata, system)?;
 
     let (main_loop, main_loop_cancellation_token) = MainLoop::new(cli_options);
 
@@ -143,18 +105,14 @@ fn run_check(args: CheckCommand) -> anyhow::Result<ExitStatus> {
     let exit_status = if watch {
         main_loop.watch(&mut db)?
     } else {
-        main_loop.run(&mut db)?
+        main_loop.run(&mut db)
     };
 
     tracing::trace!("Counts for entire CLI run:\n{}", countme::get_all());
 
     std::mem::forget(db);
 
-    if exit_zero {
-        Ok(ExitStatus::Success)
-    } else {
-        Ok(exit_status)
-    }
+    Ok(exit_status)
 }
 
 #[derive(Copy, Clone)]
@@ -203,7 +161,7 @@ impl MainLoop {
         )
     }
 
-    fn watch(mut self, db: &mut ProjectDatabase) -> Result<ExitStatus> {
+    fn watch(mut self, db: &mut ProjectDatabase) -> anyhow::Result<ExitStatus> {
         tracing::debug!("Starting watch mode");
         let sender = self.sender.clone();
         let watcher = watch::directory_watcher(move |event| {
@@ -212,12 +170,12 @@ impl MainLoop {
 
         self.watcher = Some(ProjectWatcher::new(watcher, db));
 
-        self.run(db)?;
+        self.run(db);
 
         Ok(ExitStatus::Success)
     }
 
-    fn run(mut self, db: &mut ProjectDatabase) -> Result<ExitStatus> {
+    fn run(mut self, db: &mut ProjectDatabase) -> ExitStatus {
         self.sender.send(MainLoopMessage::CheckWorkspace).unwrap();
 
         let result = self.main_loop(db);
@@ -227,7 +185,7 @@ impl MainLoop {
         result
     }
 
-    fn main_loop(&mut self, db: &mut ProjectDatabase) -> Result<ExitStatus> {
+    fn main_loop(&mut self, db: &mut ProjectDatabase) -> ExitStatus {
         // Schedule the first check.
         tracing::debug!("Starting main loop");
 
@@ -255,53 +213,11 @@ impl MainLoop {
                     result,
                     revision: check_revision,
                 } => {
-                    let display_config = DisplayDiagnosticConfig::default()
-                        .color(colored::control::SHOULD_COLORIZE.should_colorize());
-
-                    let min_error_severity =
-                        if db.project().settings(db).terminal().error_on_warning {
-                            Severity::Warning
-                        } else {
-                            Severity::Error
-                        };
-
+                    let has_diagnostics = !result.is_empty();
                     if check_revision == revision {
-                        if db.project().files(db).is_empty() {
-                            tracing::warn!("No python files found under the given path(s)");
-                        }
-
-                        let mut stdout = stdout().lock();
-
-                        if result.is_empty() {
-                            writeln!(stdout, "All checks passed!")?;
-
-                            if self.watcher.is_none() {
-                                return Ok(ExitStatus::Success);
-                            }
-                        } else {
-                            let mut failed = false;
-                            let diagnostics_count = result.len();
-
-                            for diagnostic in result {
-                                writeln!(stdout, "{}", diagnostic.display(db, &display_config))?;
-
-                                failed |= diagnostic.severity() >= min_error_severity;
-                            }
-
-                            writeln!(
-                                stdout,
-                                "Found {} diagnostic{}",
-                                diagnostics_count,
-                                if diagnostics_count > 1 { "s" } else { "" }
-                            )?;
-
-                            if self.watcher.is_none() {
-                                return Ok(if failed {
-                                    ExitStatus::Failure
-                                } else {
-                                    ExitStatus::Success
-                                });
-                            }
+                        #[allow(clippy::print_stdout)]
+                        for diagnostic in result {
+                            println!("{}", diagnostic.display(db));
                         }
                     } else {
                         tracing::debug!(
@@ -309,6 +225,14 @@ impl MainLoop {
                         );
                     }
 
+                    if self.watcher.is_none() {
+                        return if has_diagnostics {
+                            ExitStatus::Failure
+                        } else {
+                            ExitStatus::Success
+                        };
+                    }
+
                     tracing::trace!("Counts after last check:\n{}", countme::get_all());
                 }
 
@@ -326,14 +250,14 @@ impl MainLoop {
                     // TODO: Don't use Salsa internal APIs
                     //  [Zulip-Thread](https://salsa.zulipchat.com/#narrow/stream/333573-salsa-3.2E0/topic/Expose.20an.20API.20to.20cancel.20other.20queries)
                     let _ = db.zalsa_mut();
-                    return Ok(ExitStatus::Success);
+                    return ExitStatus::Success;
                 }
             }
 
             tracing::debug!("Waiting for next main loop message.");
         }
 
-        Ok(ExitStatus::Success)
+        ExitStatus::Success
     }
 }
 
@@ -353,8 +277,7 @@ impl MainLoopCancellationToken {
 enum MainLoopMessage {
     CheckWorkspace,
     CheckCompleted {
-        /// The diagnostics that were found during the check.
-        result: Vec<Box<dyn OldDiagnosticTrait>>,
+        result: Vec<Box<dyn Diagnostic>>,
         revision: u64,
     },
     ApplyChanges(Vec<watch::ChangeEvent>),

crates/red_knot/src/python_version.rs

@@ -40,7 +40,7 @@ impl std::fmt::Display for PythonVersion {
     }
 }
 
-impl From<PythonVersion> for ruff_python_ast::PythonVersion {
+impl From<PythonVersion> for red_knot_python_semantic::PythonVersion {
     fn from(value: PythonVersion) -> Self {
         match value {
             PythonVersion::Py37 => Self::PY37,
@@ -61,8 +61,8 @@ mod tests {
     #[test]
     fn same_default_as_python_version() {
         assert_eq!(
-            ruff_python_ast::PythonVersion::from(PythonVersion::default()),
-            ruff_python_ast::PythonVersion::default()
+            red_knot_python_semantic::PythonVersion::from(PythonVersion::default()),
+            red_knot_python_semantic::PythonVersion::default()
         );
     }
 }

crates/red_knot/src/verbosity.rs

@@ -0,0 +1 @@
+

crates/red_knot/src/version.rs

@@ -1,105 +0,0 @@
-//! Code for representing Red Knot's release version number.
-use std::fmt;
-
-/// Information about the git repository where Red Knot was built from.
-pub(crate) struct CommitInfo {
-    short_commit_hash: String,
-    commit_date: String,
-    commits_since_last_tag: u32,
-}
-
-/// Red Knot's version.
-pub(crate) struct VersionInfo {
-    /// Red Knot's version, such as "0.5.1"
-    version: String,
-    /// Information about the git commit we may have been built from.
-    ///
-    /// `None` if not built from a git repo or if retrieval failed.
-    commit_info: Option<CommitInfo>,
-}
-
-impl fmt::Display for VersionInfo {
-    /// Formatted version information: `<version>[+<commits>] (<commit> <date>)`
-    fn fmt(&self, f: &mut fmt::Formatter<'_>) -> fmt::Result {
-        write!(f, "{}", self.version)?;
-
-        if let Some(ref ci) = self.commit_info {
-            if ci.commits_since_last_tag > 0 {
-                write!(f, "+{}", ci.commits_since_last_tag)?;
-            }
-            write!(f, " ({} {})", ci.short_commit_hash, ci.commit_date)?;
-        }
-
-        Ok(())
-    }
-}
-
-/// Returns information about Red Knot's version.
-pub(crate) fn version() -> VersionInfo {
-    // Environment variables are only read at compile-time
-    macro_rules! option_env_str {
-        ($name:expr) => {
-            option_env!($name).map(|s| s.to_string())
-        };
-    }
-
-    // This version is pulled from Cargo.toml and set by Cargo
-    let version = option_env_str!("CARGO_PKG_VERSION").unwrap();
-
-    // Commit info is pulled from git and set by `build.rs`
-    let commit_info =
-        option_env_str!("RED_KNOT_COMMIT_SHORT_HASH").map(|short_commit_hash| CommitInfo {
-            short_commit_hash,
-            commit_date: option_env_str!("RED_KNOT_COMMIT_DATE").unwrap(),
-            commits_since_last_tag: option_env_str!("RED_KNOT_LAST_TAG_DISTANCE")
-                .as_deref()
-                .map_or(0, |value| value.parse::<u32>().unwrap_or(0)),
-        });
-
-    VersionInfo {
-        version,
-        commit_info,
-    }
-}
-
-#[cfg(test)]
-mod tests {
-    use insta::assert_snapshot;
-
-    use super::{CommitInfo, VersionInfo};
-
-    #[test]
-    fn version_formatting() {
-        let version = VersionInfo {
-            version: "0.0.0".to_string(),
-            commit_info: None,
-        };
-        assert_snapshot!(version, @"0.0.0");
-    }
-
-    #[test]
-    fn version_formatting_with_commit_info() {
-        let version = VersionInfo {
-            version: "0.0.0".to_string(),
-            commit_info: Some(CommitInfo {
-                short_commit_hash: "53b0f5d92".to_string(),
-                commit_date: "2023-10-19".to_string(),
-                commits_since_last_tag: 0,
-            }),
-        };
-        assert_snapshot!(version, @"0.0.0 (53b0f5d92 2023-10-19)");
-    }
-
-    #[test]
-    fn version_formatting_with_commits_since_last_tag() {
-        let version = VersionInfo {
-            version: "0.0.0".to_string(),
-            commit_info: Some(CommitInfo {
-                short_commit_hash: "53b0f5d92".to_string(),
-                commit_date: "2023-10-19".to_string(),
-                commits_since_last_tag: 24,
-            }),
-        };
-        assert_snapshot!(version, @"0.0.0+24 (53b0f5d92 2023-10-19)");
-    }
-}

crates/red_knot/tests/cli.rs

@@ -29,29 +29,20 @@ fn config_override() -> anyhow::Result<()> {
     ])?;
 
     assert_cmd_snapshot!(case.command(), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:unresolved-attribute
-     --> <temp_dir>/test.py:5:7
-      |
-    4 | # Access `sys.last_exc` that was only added in Python 3.12
-    5 | print(sys.last_exc)
-      |       ^^^^^^^^^^^^ Type `<module 'sys'>` has no attribute `last_exc`
-      |
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        error[lint:unresolved-attribute] <temp_dir>/test.py:5:7 Type `<module 'sys'>` has no attribute `last_exc`
 
-    Found 1 diagnostic
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     assert_cmd_snapshot!(case.command().arg("--python-version").arg("3.12"), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    All checks passed!
+        success: true
+        exit_code: 0
+        ----- stdout -----
 
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     Ok(())
@@ -100,31 +91,21 @@ fn cli_arguments_are_relative_to_the_current_directory() -> anyhow::Result<()> {
     ])?;
 
     // Make sure that the CLI fails when the `libs` directory is not in the search path.
-    assert_cmd_snapshot!(case.command().current_dir(case.root().join("child")), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:unresolved-import
-     --> <temp_dir>/child/test.py:2:6
-      |
-    2 | from utils import add
-      |      ^^^^^ Cannot resolve import `utils`
-    3 |
-    4 | stat = add(10, 15)
-      |
+    assert_cmd_snapshot!(case.command().current_dir(case.project_dir().join("child")), @r#"
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        error[lint:unresolved-import] <temp_dir>/child/test.py:2:1 Cannot resolve import `utils`
 
-    Found 1 diagnostic
+        ----- stderr -----
+    "#);
 
-    ----- stderr -----
-    ");
+    assert_cmd_snapshot!(case.command().current_dir(case.project_dir().join("child")).arg("--extra-search-path").arg("../libs"), @r"
+        success: true
+        exit_code: 0
+        ----- stdout -----
 
-    assert_cmd_snapshot!(case.command().current_dir(case.root().join("child")).arg("--extra-search-path").arg("../libs"), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    All checks passed!
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     Ok(())
@@ -171,13 +152,12 @@ fn paths_in_configuration_files_are_relative_to_the_project_root() -> anyhow::Re
         ),
     ])?;
 
-    assert_cmd_snapshot!(case.command().current_dir(case.root().join("child")), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    All checks passed!
+    assert_cmd_snapshot!(case.command().current_dir(case.project_dir().join("child")), @r"
+        success: true
+        exit_code: 0
+        ----- stdout -----
 
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     Ok(())
@@ -201,30 +181,13 @@ fn configuration_rule_severity() -> anyhow::Result<()> {
     // Assert that there's a possibly unresolved reference diagnostic
     // and that division-by-zero has a severity of error by default.
     assert_cmd_snapshot!(case.command(), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:division-by-zero
-     --> <temp_dir>/test.py:2:5
-      |
-    2 | y = 4 / 0
-      |     ^^^^^ Cannot divide object of type `Literal[4]` by zero
-    3 |
-    4 | for a in range(0, y):
-      |
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        error[lint:division-by-zero] <temp_dir>/test.py:2:5 Cannot divide object of type `Literal[4]` by zero
+        warning[lint:possibly-unresolved-reference] <temp_dir>/test.py:7:7 Name `x` used when possibly not defined
 
-    warning: lint:possibly-unresolved-reference
-     --> <temp_dir>/test.py:7:7
-      |
-    5 |     x = a
-    6 |
-    7 | print(x)  # possibly-unresolved-reference
-      |       - Name `x` used when possibly not defined
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     case.write_file(
@@ -237,21 +200,12 @@ fn configuration_rule_severity() -> anyhow::Result<()> {
     )?;
 
     assert_cmd_snapshot!(case.command(), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: lint:division-by-zero
-     --> <temp_dir>/test.py:2:5
-      |
-    2 | y = 4 / 0
-      |     ----- Cannot divide object of type `Literal[4]` by zero
-    3 |
-    4 | for a in range(0, y):
-      |
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        warning[lint:division-by-zero] <temp_dir>/test.py:2:5 Cannot divide object of type `Literal[4]` by zero
 
-    Found 1 diagnostic
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     Ok(())
@@ -277,41 +231,14 @@ fn cli_rule_severity() -> anyhow::Result<()> {
     // Assert that there's a possibly unresolved reference diagnostic
     // and that division-by-zero has a severity of error by default.
     assert_cmd_snapshot!(case.command(), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:unresolved-import
-     --> <temp_dir>/test.py:2:8
-      |
-    2 | import does_not_exit
-      |        ^^^^^^^^^^^^^ Cannot resolve import `does_not_exit`
-    3 |
-    4 | y = 4 / 0
-      |
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        error[lint:unresolved-import] <temp_dir>/test.py:2:8 Cannot resolve import `does_not_exit`
+        error[lint:division-by-zero] <temp_dir>/test.py:4:5 Cannot divide object of type `Literal[4]` by zero
+        warning[lint:possibly-unresolved-reference] <temp_dir>/test.py:9:7 Name `x` used when possibly not defined
 
-    error: lint:division-by-zero
-     --> <temp_dir>/test.py:4:5
-      |
-    2 | import does_not_exit
-    3 |
-    4 | y = 4 / 0
-      |     ^^^^^ Cannot divide object of type `Literal[4]` by zero
-    5 |
-    6 | for a in range(0, y):
-      |
-
-    warning: lint:possibly-unresolved-reference
-     --> <temp_dir>/test.py:9:7
-      |
-    7 |     x = a
-    8 |
-    9 | print(x)  # possibly-unresolved-reference
-      |       - Name `x` used when possibly not defined
-      |
-
-    Found 3 diagnostics
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     assert_cmd_snapshot!(
@@ -324,30 +251,11 @@ fn cli_rule_severity() -> anyhow::Result<()> {
             .arg("--warn")
             .arg("unresolved-import"),
         @r"
-    success: true
-    exit_code: 0
+    success: false
+    exit_code: 1
     ----- stdout -----
-    warning: lint:unresolved-import
-     --> <temp_dir>/test.py:2:8
-      |
-    2 | import does_not_exit
-      |        ------------- Cannot resolve import `does_not_exit`
-    3 |
-    4 | y = 4 / 0
-      |
-
-    warning: lint:division-by-zero
-     --> <temp_dir>/test.py:4:5
-      |
-    2 | import does_not_exit
-    3 |
-    4 | y = 4 / 0
-      |     ----- Cannot divide object of type `Literal[4]` by zero
-    5 |
-    6 | for a in range(0, y):
-      |
-
-    Found 2 diagnostics
+    warning[lint:unresolved-import] <temp_dir>/test.py:2:8 Cannot resolve import `does_not_exit`
+    warning[lint:division-by-zero] <temp_dir>/test.py:4:5 Cannot divide object of type `Literal[4]` by zero
 
     ----- stderr -----
     "
@@ -375,30 +283,13 @@ fn cli_rule_severity_precedence() -> anyhow::Result<()> {
     // Assert that there's a possibly unresolved reference diagnostic
     // and that division-by-zero has a severity of error by default.
     assert_cmd_snapshot!(case.command(), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:division-by-zero
-     --> <temp_dir>/test.py:2:5
-      |
-    2 | y = 4 / 0
-      |     ^^^^^ Cannot divide object of type `Literal[4]` by zero
-    3 |
-    4 | for a in range(0, y):
-      |
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        error[lint:division-by-zero] <temp_dir>/test.py:2:5 Cannot divide object of type `Literal[4]` by zero
+        warning[lint:possibly-unresolved-reference] <temp_dir>/test.py:7:7 Name `x` used when possibly not defined
 
-    warning: lint:possibly-unresolved-reference
-     --> <temp_dir>/test.py:7:7
-      |
-    5 |     x = a
-    6 |
-    7 | print(x)  # possibly-unresolved-reference
-      |       - Name `x` used when possibly not defined
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     assert_cmd_snapshot!(
@@ -412,22 +303,13 @@ fn cli_rule_severity_precedence() -> anyhow::Result<()> {
             .arg("--ignore")
             .arg("possibly-unresolved-reference"),
         @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: lint:division-by-zero
-     --> <temp_dir>/test.py:2:5
-      |
-    2 | y = 4 / 0
-      |     ----- Cannot divide object of type `Literal[4]` by zero
-    3 |
-    4 | for a in range(0, y):
-      |
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        warning[lint:division-by-zero] <temp_dir>/test.py:2:5 Cannot divide object of type `Literal[4]` by zero
 
-    Found 1 diagnostic
-
-    ----- stderr -----
-    "
+        ----- stderr -----
+        "
     );
 
     Ok(())
@@ -447,22 +329,14 @@ fn configuration_unknown_rules() -> anyhow::Result<()> {
         ("test.py", "print(10)"),
     ])?;
 
-    assert_cmd_snapshot!(case.command(), @r#"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: unknown-rule
-     --> <temp_dir>/pyproject.toml:3:1
-      |
-    2 | [tool.knot.rules]
-    3 | division-by-zer = "warn" # incorrect rule name
-      | --------------- Unknown lint rule `division-by-zer`
-      |
+    assert_cmd_snapshot!(case.command(), @r"
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        warning[unknown-rule] <temp_dir>/pyproject.toml:3:1 Unknown lint rule `division-by-zer`
 
-    Found 1 diagnostic
-
-    ----- stderr -----
-    "#);
+        ----- stderr -----
+    ");
 
     Ok(())
 }
@@ -473,500 +347,17 @@ fn cli_unknown_rules() -> anyhow::Result<()> {
     let case = TestCase::with_file("test.py", "print(10)")?;
 
     assert_cmd_snapshot!(case.command().arg("--ignore").arg("division-by-zer"), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: unknown-rule: Unknown lint rule `division-by-zer`
+        success: false
+        exit_code: 1
+        ----- stdout -----
+        warning[unknown-rule] Unknown lint rule `division-by-zer`
 
-    Found 1 diagnostic
-
-    ----- stderr -----
+        ----- stderr -----
     ");
 
     Ok(())
 }
 
-#[test]
-fn exit_code_only_warnings() -> anyhow::Result<()> {
-    let case = TestCase::with_file("test.py", r"print(x)  # [unresolved-reference]")?;
-
-    assert_cmd_snapshot!(case.command(), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: lint:unresolved-reference
-     --> <temp_dir>/test.py:1:7
-      |
-    1 | print(x)  # [unresolved-reference]
-      |       - Name `x` used when not defined
-      |
-
-    Found 1 diagnostic
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_only_info() -> anyhow::Result<()> {
-    let case = TestCase::with_file(
-        "test.py",
-        r#"
-        from typing_extensions import reveal_type
-        reveal_type(1)
-        "#,
-    )?;
-
-    assert_cmd_snapshot!(case.command(), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    info: revealed-type
-     --> <temp_dir>/test.py:3:1
-      |
-    2 | from typing_extensions import reveal_type
-    3 | reveal_type(1)
-      | -------------- info: Revealed type is `Literal[1]`
-      |
-
-    Found 1 diagnostic
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_only_info_and_error_on_warning_is_true() -> anyhow::Result<()> {
-    let case = TestCase::with_file(
-        "test.py",
-        r#"
-        from typing_extensions import reveal_type
-        reveal_type(1)
-        "#,
-    )?;
-
-    assert_cmd_snapshot!(case.command().arg("--error-on-warning"), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    info: revealed-type
-     --> <temp_dir>/test.py:3:1
-      |
-    2 | from typing_extensions import reveal_type
-    3 | reveal_type(1)
-      | -------------- info: Revealed type is `Literal[1]`
-      |
-
-    Found 1 diagnostic
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_no_errors_but_error_on_warning_is_true() -> anyhow::Result<()> {
-    let case = TestCase::with_file("test.py", r"print(x)  # [unresolved-reference]")?;
-
-    assert_cmd_snapshot!(case.command().arg("--error-on-warning"), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    warning: lint:unresolved-reference
-     --> <temp_dir>/test.py:1:7
-      |
-    1 | print(x)  # [unresolved-reference]
-      |       - Name `x` used when not defined
-      |
-
-    Found 1 diagnostic
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_no_errors_but_error_on_warning_is_enabled_in_configuration() -> anyhow::Result<()> {
-    let case = TestCase::with_files([
-        ("test.py", r"print(x)  # [unresolved-reference]"),
-        (
-            "knot.toml",
-            r#"
-            [terminal]
-            error-on-warning = true
-        "#,
-        ),
-    ])?;
-
-    assert_cmd_snapshot!(case.command(), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    warning: lint:unresolved-reference
-     --> <temp_dir>/test.py:1:7
-      |
-    1 | print(x)  # [unresolved-reference]
-      |       - Name `x` used when not defined
-      |
-
-    Found 1 diagnostic
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_both_warnings_and_errors() -> anyhow::Result<()> {
-    let case = TestCase::with_file(
-        "test.py",
-        r#"
-        print(x)     # [unresolved-reference]
-        print(4[1])  # [non-subscriptable]
-        "#,
-    )?;
-
-    assert_cmd_snapshot!(case.command(), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    warning: lint:unresolved-reference
-     --> <temp_dir>/test.py:2:7
-      |
-    2 | print(x)     # [unresolved-reference]
-      |       - Name `x` used when not defined
-    3 | print(4[1])  # [non-subscriptable]
-      |
-
-    error: lint:non-subscriptable
-     --> <temp_dir>/test.py:3:7
-      |
-    2 | print(x)     # [unresolved-reference]
-    3 | print(4[1])  # [non-subscriptable]
-      |       ^ Cannot subscript object of type `Literal[4]` with no `__getitem__` method
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_both_warnings_and_errors_and_error_on_warning_is_true() -> anyhow::Result<()> {
-    let case = TestCase::with_file(
-        "test.py",
-        r###"
-        print(x)     # [unresolved-reference]
-        print(4[1])  # [non-subscriptable]
-        "###,
-    )?;
-
-    assert_cmd_snapshot!(case.command().arg("--error-on-warning"), @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    warning: lint:unresolved-reference
-     --> <temp_dir>/test.py:2:7
-      |
-    2 | print(x)     # [unresolved-reference]
-      |       - Name `x` used when not defined
-    3 | print(4[1])  # [non-subscriptable]
-      |
-
-    error: lint:non-subscriptable
-     --> <temp_dir>/test.py:3:7
-      |
-    2 | print(x)     # [unresolved-reference]
-    3 | print(4[1])  # [non-subscriptable]
-      |       ^ Cannot subscript object of type `Literal[4]` with no `__getitem__` method
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn exit_code_exit_zero_is_true() -> anyhow::Result<()> {
-    let case = TestCase::with_file(
-        "test.py",
-        r#"
-        print(x)     # [unresolved-reference]
-        print(4[1])  # [non-subscriptable]
-        "#,
-    )?;
-
-    assert_cmd_snapshot!(case.command().arg("--exit-zero"), @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: lint:unresolved-reference
-     --> <temp_dir>/test.py:2:7
-      |
-    2 | print(x)     # [unresolved-reference]
-      |       - Name `x` used when not defined
-    3 | print(4[1])  # [non-subscriptable]
-      |
-
-    error: lint:non-subscriptable
-     --> <temp_dir>/test.py:3:7
-      |
-    2 | print(x)     # [unresolved-reference]
-    3 | print(4[1])  # [non-subscriptable]
-      |       ^ Cannot subscript object of type `Literal[4]` with no `__getitem__` method
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    ");
-
-    Ok(())
-}
-
-#[test]
-fn user_configuration() -> anyhow::Result<()> {
-    let case = TestCase::with_files([
-        (
-            "project/knot.toml",
-            r#"
-            [rules]
-            division-by-zero = "warn"
-            "#,
-        ),
-        (
-            "project/main.py",
-            r#"
-            y = 4 / 0
-
-            for a in range(0, y):
-                x = a
-
-            print(x)
-            "#,
-        ),
-    ])?;
-
-    let config_directory = case.root().join("home/.config");
-    let config_env_var = if cfg!(windows) {
-        "APPDATA"
-    } else {
-        "XDG_CONFIG_HOME"
-    };
-
-    assert_cmd_snapshot!(
-        case.command().current_dir(case.root().join("project")).env(config_env_var, config_directory.as_os_str()),
-        @r"
-    success: true
-    exit_code: 0
-    ----- stdout -----
-    warning: lint:division-by-zero
-     --> <temp_dir>/project/main.py:2:5
-      |
-    2 | y = 4 / 0
-      |     ----- Cannot divide object of type `Literal[4]` by zero
-    3 |
-    4 | for a in range(0, y):
-      |
-
-    warning: lint:possibly-unresolved-reference
-     --> <temp_dir>/project/main.py:7:7
-      |
-    5 |     x = a
-    6 |
-    7 | print(x)
-      |       - Name `x` used when possibly not defined
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    "
-    );
-
-    // The user-level configuration promotes `possibly-unresolved-reference` to an error.
-    // Changing the level for `division-by-zero` has no effect, because the project-level configuration
-    // has higher precedence.
-    case.write_file(
-        config_directory.join("knot/knot.toml"),
-        r#"
-        [rules]
-        division-by-zero = "error"
-        possibly-unresolved-reference = "error"
-        "#,
-    )?;
-
-    assert_cmd_snapshot!(
-        case.command().current_dir(case.root().join("project")).env(config_env_var, config_directory.as_os_str()),
-        @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    warning: lint:division-by-zero
-     --> <temp_dir>/project/main.py:2:5
-      |
-    2 | y = 4 / 0
-      |     ----- Cannot divide object of type `Literal[4]` by zero
-    3 |
-    4 | for a in range(0, y):
-      |
-
-    error: lint:possibly-unresolved-reference
-     --> <temp_dir>/project/main.py:7:7
-      |
-    5 |     x = a
-    6 |
-    7 | print(x)
-      |       ^ Name `x` used when possibly not defined
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    "
-    );
-
-    Ok(())
-}
-
-#[test]
-fn check_specific_paths() -> anyhow::Result<()> {
-    let case = TestCase::with_files([
-        (
-            "project/main.py",
-            r#"
-            y = 4 / 0  # error: division-by-zero
-            "#,
-        ),
-        (
-            "project/tests/test_main.py",
-            r#"
-            import does_not_exist  # error: unresolved-import
-            "#,
-        ),
-        (
-            "project/other.py",
-            r#"
-            from main2 import z  # error: unresolved-import
-
-            print(z)
-            "#,
-        ),
-    ])?;
-
-    assert_cmd_snapshot!(
-        case.command(),
-        @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:unresolved-import
-     --> <temp_dir>/project/tests/test_main.py:2:8
-      |
-    2 | import does_not_exist  # error: unresolved-import
-      |        ^^^^^^^^^^^^^^ Cannot resolve import `does_not_exist`
-      |
-
-    error: lint:division-by-zero
-     --> <temp_dir>/project/main.py:2:5
-      |
-    2 | y = 4 / 0  # error: division-by-zero
-      |     ^^^^^ Cannot divide object of type `Literal[4]` by zero
-      |
-
-    error: lint:unresolved-import
-     --> <temp_dir>/project/other.py:2:6
-      |
-    2 | from main2 import z  # error: unresolved-import
-      |      ^^^^^ Cannot resolve import `main2`
-    3 |
-    4 | print(z)
-      |
-
-    Found 3 diagnostics
-
-    ----- stderr -----
-    "
-    );
-
-    // Now check only the `tests` and `other.py` files.
-    // We should no longer see any diagnostics related to `main.py`.
-    assert_cmd_snapshot!(
-        case.command().arg("project/tests").arg("project/other.py"),
-        @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: lint:unresolved-import
-     --> <temp_dir>/project/tests/test_main.py:2:8
-      |
-    2 | import does_not_exist  # error: unresolved-import
-      |        ^^^^^^^^^^^^^^ Cannot resolve import `does_not_exist`
-      |
-
-    error: lint:unresolved-import
-     --> <temp_dir>/project/other.py:2:6
-      |
-    2 | from main2 import z  # error: unresolved-import
-      |      ^^^^^ Cannot resolve import `main2`
-    3 |
-    4 | print(z)
-      |
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    "
-    );
-
-    Ok(())
-}
-
-#[test]
-fn check_non_existing_path() -> anyhow::Result<()> {
-    let case = TestCase::with_files([])?;
-
-    let mut settings = insta::Settings::clone_current();
-    settings.add_filter(
-        &regex::escape("The system cannot find the path specified. (os error 3)"),
-        "No such file or directory (os error 2)",
-    );
-    let _s = settings.bind_to_scope();
-
-    assert_cmd_snapshot!(
-        case.command().arg("project/main.py").arg("project/tests"),
-        @r"
-    success: false
-    exit_code: 1
-    ----- stdout -----
-    error: io: `<temp_dir>/project/main.py`: No such file or directory (os error 2)
-
-    error: io: `<temp_dir>/project/tests`: No such file or directory (os error 2)
-
-    Found 2 diagnostics
-
-    ----- stderr -----
-    WARN No python files found under the given path(s)
-    "
-    );
-
-    Ok(())
-}
-
 struct TestCase {
     _temp_dir: TempDir,
     _settings_scope: SettingsBindDropGuard,
@@ -1034,7 +425,7 @@ impl TestCase {
         Ok(())
     }
 
-    fn root(&self) -> &Path {
+    fn project_dir(&self) -> &Path {
         &self.project_dir
     }
 

crates/red_knot/tests/file_watching.rs

@@ -1,6 +1,5 @@
 #![allow(clippy::disallowed_names)]
 
-use std::collections::HashSet;
 use std::io::Write;
 use std::time::{Duration, Instant};
 
@@ -10,14 +9,11 @@ use red_knot_project::metadata::pyproject::{PyProject, Tool};
 use red_knot_project::metadata::value::{RangedValue, RelativePathBuf};
 use red_knot_project::watch::{directory_watcher, ChangeEvent, ProjectWatcher};
 use red_knot_project::{Db, ProjectDatabase, ProjectMetadata};
-use red_knot_python_semantic::{resolve_module, ModuleName, PythonPlatform};
+use red_knot_python_semantic::{resolve_module, ModuleName, PythonPlatform, PythonVersion};
 use ruff_db::files::{system_path_to_file, File, FileError};
 use ruff_db::source::source_text;
-use ruff_db::system::{
-    OsSystem, System, SystemPath, SystemPathBuf, UserConfigDirectoryOverrideGuard,
-};
+use ruff_db::system::{OsSystem, SystemPath, SystemPathBuf};
 use ruff_db::Upcast;
-use ruff_python_ast::PythonVersion;
 
 struct TestCase {
     db: ProjectDatabase,
@@ -194,29 +190,11 @@ impl TestCase {
         Ok(())
     }
 
-    #[track_caller]
-    fn assert_indexed_project_files(&self, expected: impl IntoIterator<Item = File>) {
-        let mut expected: HashSet<_> = expected.into_iter().collect();
-
-        let actual = self.db().project().files(self.db());
-        for file in &actual {
-            assert!(
-                expected.remove(&file),
-                "Indexed project files contains '{}' which was not expected.",
-                file.path(self.db())
-            );
-        }
-
-        if !expected.is_empty() {
-            let paths: Vec<_> = expected
-                .iter()
-                .map(|file| file.path(self.db()).as_str())
-                .collect();
-            panic!(
-                "Indexed project files are missing the following files: {:?}",
-                paths.join(", ")
-            );
-        }
+    fn collect_project_files(&self) -> Vec<File> {
+        let files = self.db().project().files(self.db());
+        let mut collected: Vec<_> = files.into_iter().collect();
+        collected.sort_unstable_by_key(|file| file.path(self.db()).as_system_path().unwrap());
+        collected
     }
 
     fn system_file(&self, path: impl AsRef<SystemPath>) -> Result<File, FileError> {
@@ -241,108 +219,58 @@ where
     }
 }
 
-trait Setup {
-    fn setup(self, context: &mut SetupContext) -> anyhow::Result<()>;
+trait SetupFiles {
+    fn setup(self, root_path: &SystemPath, project_path: &SystemPath) -> anyhow::Result<()>;
 }
 
-struct SetupContext<'a> {
-    system: &'a OsSystem,
-    root_path: &'a SystemPath,
-    options: Option<Options>,
-    included_paths: Option<Vec<SystemPathBuf>>,
-}
-
-impl<'a> SetupContext<'a> {
-    fn system(&self) -> &'a OsSystem {
-        self.system
-    }
-
-    fn join_project_path(&self, relative: impl AsRef<SystemPath>) -> SystemPathBuf {
-        self.project_path().join(relative)
-    }
-
-    fn project_path(&self) -> &SystemPath {
-        self.system.current_directory()
-    }
-
-    fn root_path(&self) -> &'a SystemPath {
-        self.root_path
-    }
-
-    fn join_root_path(&self, relative: impl AsRef<SystemPath>) -> SystemPathBuf {
-        self.root_path().join(relative)
-    }
-
-    fn write_project_file(
-        &self,
-        relative_path: impl AsRef<SystemPath>,
-        content: &str,
-    ) -> anyhow::Result<()> {
-        let relative_path = relative_path.as_ref();
-        let absolute_path = self.join_project_path(relative_path);
-        Self::write_file_impl(absolute_path, content)
-    }
-
-    fn write_file(
-        &self,
-        relative_path: impl AsRef<SystemPath>,
-        content: &str,
-    ) -> anyhow::Result<()> {
-        let relative_path = relative_path.as_ref();
-        let absolute_path = self.join_root_path(relative_path);
-        Self::write_file_impl(absolute_path, content)
-    }
-
-    fn write_file_impl(path: impl AsRef<SystemPath>, content: &str) -> anyhow::Result<()> {
-        let path = path.as_ref();
-        if let Some(parent) = path.parent() {
-            std::fs::create_dir_all(parent)
-                .with_context(|| format!("Failed to create parent directory for file `{path}`"))?;
-        }
-
-        let mut file = std::fs::File::create(path.as_std_path())
-            .with_context(|| format!("Failed to open file `{path}`"))?;
-        file.write_all(content.as_bytes())
-            .with_context(|| format!("Failed to write to file `{path}`"))?;
-        file.sync_data()?;
-
-        Ok(())
-    }
-
-    fn set_options(&mut self, options: Options) {
-        self.options = Some(options);
-    }
-
-    fn set_included_paths(&mut self, paths: Vec<SystemPathBuf>) {
-        self.included_paths = Some(paths);
-    }
-}
-
-impl<const N: usize, P> Setup for [(P, &'static str); N]
+impl<const N: usize, P> SetupFiles for [(P, &'static str); N]
 where
     P: AsRef<SystemPath>,
 {
-    fn setup(self, context: &mut SetupContext) -> anyhow::Result<()> {
+    fn setup(self, _root_path: &SystemPath, project_path: &SystemPath) -> anyhow::Result<()> {
         for (relative_path, content) in self {
-            context.write_project_file(relative_path, content)?;
+            let relative_path = relative_path.as_ref();
+            let absolute_path = project_path.join(relative_path);
+            if let Some(parent) = absolute_path.parent() {
+                std::fs::create_dir_all(parent).with_context(|| {
+                    format!("Failed to create parent directory for file `{relative_path}`")
+                })?;
+            }
+
+            let mut file = std::fs::File::create(absolute_path.as_std_path())
+                .with_context(|| format!("Failed to open file `{relative_path}`"))?;
+            file.write_all(content.as_bytes())
+                .with_context(|| format!("Failed to write to file `{relative_path}`"))?;
+            file.sync_data()?;
         }
 
         Ok(())
     }
 }
 
-impl<F> Setup for F
+impl<F> SetupFiles for F
 where
-    F: FnOnce(&mut SetupContext) -> anyhow::Result<()>,
+    F: FnOnce(&SystemPath, &SystemPath) -> anyhow::Result<()>,
 {
-    fn setup(self, context: &mut SetupContext) -> anyhow::Result<()> {
-        self(context)
+    fn setup(self, root_path: &SystemPath, project_path: &SystemPath) -> anyhow::Result<()> {
+        self(root_path, project_path)
     }
 }
 
 fn setup<F>(setup_files: F) -> anyhow::Result<TestCase>
 where
-    F: Setup,
+    F: SetupFiles,
+{
+    setup_with_options(setup_files, |_root, _project_path| None)
+}
+
+// TODO: Replace with configuration?
+fn setup_with_options<F>(
+    setup_files: F,
+    create_options: impl FnOnce(&SystemPath, &SystemPath) -> Option<Options>,
+) -> anyhow::Result<TestCase>
+where
+    F: SetupFiles,
 {
     let temp_dir = tempfile::tempdir()?;
 
@@ -367,19 +295,13 @@ where
     std::fs::create_dir_all(project_path.as_std_path())
         .with_context(|| format!("Failed to create project directory `{project_path}`"))?;
 
-    let system = OsSystem::new(&project_path);
-    let mut setup_context = SetupContext {
-        system: &system,
-        root_path: &root_path,
-        options: None,
-        included_paths: None,
-    };
-
     setup_files
-        .setup(&mut setup_context)
+        .setup(&root_path, &project_path)
         .context("Failed to setup test files")?;
 
-    if let Some(options) = setup_context.options {
+    let system = OsSystem::new(&project_path);
+
+    if let Some(options) = create_options(&root_path, &project_path) {
         std::fs::write(
             project_path.join("pyproject.toml").as_std_path(),
             toml::to_string(&PyProject {
@@ -393,11 +315,7 @@ where
         .context("Failed to write configuration")?;
     }
 
-    let included_paths = setup_context.included_paths;
-
-    let mut project = ProjectMetadata::discover(&project_path, &system)?;
-    project.apply_configuration_files(&system)?;
-
+    let project = ProjectMetadata::discover(&project_path, &system)?;
     let program_settings = project.to_program_settings(&system);
 
     for path in program_settings
@@ -410,11 +328,7 @@ where
             .with_context(|| format!("Failed to create search path `{path}`"))?;
     }
 
-    let mut db = ProjectDatabase::new(project, system)?;
-
-    if let Some(included_paths) = included_paths {
-        db.project().set_included_paths(&mut db, included_paths);
-    }
+    let db = ProjectDatabase::new(project, system)?;
 
     let (sender, receiver) = crossbeam::channel::unbounded();
     let watcher = directory_watcher(move |events| sender.send(events).unwrap())
@@ -476,7 +390,7 @@ fn new_file() -> anyhow::Result<()> {
     let foo_path = case.project_path("foo.py");
 
     assert_eq!(case.system_file(&foo_path), Err(FileError::NotFound));
-    case.assert_indexed_project_files([bar_file]);
+    assert_eq!(&case.collect_project_files(), &[bar_file]);
 
     std::fs::write(foo_path.as_std_path(), "print('Hello')")?;
 
@@ -486,7 +400,7 @@ fn new_file() -> anyhow::Result<()> {
 
     let foo = case.system_file(&foo_path).expect("foo.py to exist.");
 
-    case.assert_indexed_project_files([bar_file, foo]);
+    assert_eq!(&case.collect_project_files(), &[bar_file, foo]);
 
     Ok(())
 }
@@ -499,7 +413,7 @@ fn new_ignored_file() -> anyhow::Result<()> {
     let foo_path = case.project_path("foo.py");
 
     assert_eq!(case.system_file(&foo_path), Err(FileError::NotFound));
-    case.assert_indexed_project_files([bar_file]);
+    assert_eq!(&case.collect_project_files(), &[bar_file]);
 
     std::fs::write(foo_path.as_std_path(), "print('Hello')")?;
 
@@ -508,132 +422,7 @@ fn new_ignored_file() -> anyhow::Result<()> {
     case.apply_changes(changes);
 
     assert!(case.system_file(&foo_path).is_ok());
-    case.assert_indexed_project_files([bar_file]);
-
-    Ok(())
-}
-
-#[test]
-fn new_non_project_file() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        context.write_project_file("bar.py", "")?;
-        context.set_options(Options {
-            environment: Some(EnvironmentOptions {
-                extra_paths: Some(vec![RelativePathBuf::cli(
-                    context.join_root_path("site_packages"),
-                )]),
-                ..EnvironmentOptions::default()
-            }),
-            ..Options::default()
-        });
-
-        Ok(())
-    })?;
-
-    let bar_path = case.project_path("bar.py");
-    let bar_file = case.system_file(&bar_path).unwrap();
-
-    case.assert_indexed_project_files([bar_file]);
-
-    // Add a file to site packages
-    let black_path = case.root_path().join("site_packages/black.py");
-    std::fs::write(black_path.as_std_path(), "print('Hello')")?;
-
-    let changes = case.stop_watch(event_for_file("black.py"));
-
-    case.apply_changes(changes);
-
-    assert!(case.system_file(&black_path).is_ok());
-
-    // The file should not have been added to the project files
-    case.assert_indexed_project_files([bar_file]);
-
-    Ok(())
-}
-
-#[test]
-fn new_files_with_explicit_included_paths() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        context.write_project_file("src/main.py", "")?;
-        context.write_project_file("src/sub/__init__.py", "")?;
-        context.write_project_file("src/test.py", "")?;
-        context.set_included_paths(vec![
-            context.join_project_path("src/main.py"),
-            context.join_project_path("src/sub"),
-        ]);
-        Ok(())
-    })?;
-
-    let main_path = case.project_path("src/main.py");
-    let main_file = case.system_file(&main_path).unwrap();
-
-    let sub_init_path = case.project_path("src/sub/__init__.py");
-    let sub_init = case.system_file(&sub_init_path).unwrap();
-
-    case.assert_indexed_project_files([main_file, sub_init]);
-
-    // Write a new file to `sub` which is an included path
-    let sub_a_path = case.project_path("src/sub/a.py");
-    std::fs::write(sub_a_path.as_std_path(), "print('Hello')")?;
-
-    // and write a second file in the root directory -- this should not be included
-    let test2_path = case.project_path("src/test2.py");
-    std::fs::write(test2_path.as_std_path(), "print('Hello')")?;
-
-    let changes = case.stop_watch(event_for_file("test2.py"));
-
-    case.apply_changes(changes);
-
-    let sub_a_file = case.system_file(&sub_a_path).expect("sub/a.py to exist");
-
-    case.assert_indexed_project_files([main_file, sub_init, sub_a_file]);
-
-    Ok(())
-}
-
-#[test]
-fn new_file_in_included_out_of_project_directory() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        context.write_project_file("src/main.py", "")?;
-        context.write_project_file("script.py", "")?;
-        context.write_file("outside_project/a.py", "")?;
-
-        context.set_included_paths(vec![
-            context.join_root_path("outside_project"),
-            context.join_project_path("src"),
-        ]);
-        Ok(())
-    })?;
-
-    let main_path = case.project_path("src/main.py");
-    let main_file = case.system_file(&main_path).unwrap();
-
-    let outside_a_path = case.root_path().join("outside_project/a.py");
-    let outside_a = case.system_file(&outside_a_path).unwrap();
-
-    case.assert_indexed_project_files([outside_a, main_file]);
-
-    // Write a new file to `src` which should be watched
-    let src_a = case.project_path("src/a.py");
-    std::fs::write(src_a.as_std_path(), "print('Hello')")?;
-
-    // and write a second file to `outside_project` which should be watched too
-    let outside_b_path = case.root_path().join("outside_project/b.py");
-    std::fs::write(outside_b_path.as_std_path(), "print('Hello')")?;
-
-    // and a third file in the project's root that should not be included
-    let script2_path = case.project_path("script2.py");
-    std::fs::write(script2_path.as_std_path(), "print('Hello')")?;
-
-    let changes = case.stop_watch(event_for_file("script2.py"));
-
-    case.apply_changes(changes);
-
-    let src_a_file = case.system_file(&src_a).unwrap();
-    let outside_b_file = case.system_file(&outside_b_path).unwrap();
-
-    // The file should not have been added to the project files
-    case.assert_indexed_project_files([main_file, outside_a, outside_b_file, src_a_file]);
+    assert_eq!(&case.collect_project_files(), &[bar_file]);
 
     Ok(())
 }
@@ -646,7 +435,7 @@ fn changed_file() -> anyhow::Result<()> {
 
     let foo = case.system_file(&foo_path)?;
     assert_eq!(source_text(case.db(), foo).as_str(), foo_source);
-    case.assert_indexed_project_files([foo]);
+    assert_eq!(&case.collect_project_files(), &[foo]);
 
     update_file(&foo_path, "print('Version 2')")?;
 
@@ -657,7 +446,7 @@ fn changed_file() -> anyhow::Result<()> {
     case.apply_changes(changes);
 
     assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 2')");
-    case.assert_indexed_project_files([foo]);
+    assert_eq!(&case.collect_project_files(), &[foo]);
 
     Ok(())
 }
@@ -671,7 +460,7 @@ fn deleted_file() -> anyhow::Result<()> {
     let foo = case.system_file(&foo_path)?;
 
     assert!(foo.exists(case.db()));
-    case.assert_indexed_project_files([foo]);
+    assert_eq!(&case.collect_project_files(), &[foo]);
 
     std::fs::remove_file(foo_path.as_std_path())?;
 
@@ -680,7 +469,7 @@ fn deleted_file() -> anyhow::Result<()> {
     case.apply_changes(changes);
 
     assert!(!foo.exists(case.db()));
-    case.assert_indexed_project_files([]);
+    assert_eq!(&case.collect_project_files(), &[] as &[File]);
 
     Ok(())
 }
@@ -700,7 +489,7 @@ fn move_file_to_trash() -> anyhow::Result<()> {
     let foo = case.system_file(&foo_path)?;
 
     assert!(foo.exists(case.db()));
-    case.assert_indexed_project_files([foo]);
+    assert_eq!(&case.collect_project_files(), &[foo]);
 
     std::fs::rename(
         foo_path.as_std_path(),
@@ -712,7 +501,7 @@ fn move_file_to_trash() -> anyhow::Result<()> {
     case.apply_changes(changes);
 
     assert!(!foo.exists(case.db()));
-    case.assert_indexed_project_files([]);
+    assert_eq!(&case.collect_project_files(), &[] as &[File]);
 
     Ok(())
 }
@@ -730,7 +519,7 @@ fn move_file_to_project() -> anyhow::Result<()> {
     let foo_in_project = case.project_path("foo.py");
 
     assert!(case.system_file(&foo_path).is_ok());
-    case.assert_indexed_project_files([bar]);
+    assert_eq!(&case.collect_project_files(), &[bar]);
 
     std::fs::rename(foo_path.as_std_path(), foo_in_project.as_std_path())?;
 
@@ -741,7 +530,7 @@ fn move_file_to_project() -> anyhow::Result<()> {
     let foo_in_project = case.system_file(&foo_in_project)?;
 
     assert!(foo_in_project.exists(case.db()));
-    case.assert_indexed_project_files([bar, foo_in_project]);
+    assert_eq!(&case.collect_project_files(), &[bar, foo_in_project]);
 
     Ok(())
 }
@@ -755,7 +544,7 @@ fn rename_file() -> anyhow::Result<()> {
 
     let foo = case.system_file(&foo_path)?;
 
-    case.assert_indexed_project_files([foo]);
+    assert_eq!(case.collect_project_files(), [foo]);
 
     std::fs::rename(foo_path.as_std_path(), bar_path.as_std_path())?;
 
@@ -768,7 +557,7 @@ fn rename_file() -> anyhow::Result<()> {
     let bar = case.system_file(&bar_path)?;
 
     assert!(bar.exists(case.db()));
-    case.assert_indexed_project_files([bar]);
+    assert_eq!(case.collect_project_files(), [bar]);
 
     Ok(())
 }
@@ -794,7 +583,7 @@ fn directory_moved_to_project() -> anyhow::Result<()> {
     );
 
     assert_eq!(sub_a_module, None);
-    case.assert_indexed_project_files([bar]);
+    assert_eq!(case.collect_project_files(), &[bar]);
 
     let sub_new_path = case.project_path("sub");
     std::fs::rename(sub_original_path.as_std_path(), sub_new_path.as_std_path())
@@ -818,7 +607,7 @@ fn directory_moved_to_project() -> anyhow::Result<()> {
     )
     .is_some());
 
-    case.assert_indexed_project_files([bar, init_file, a_file]);
+    assert_eq!(case.collect_project_files(), &[bar, init_file, a_file]);
 
     Ok(())
 }
@@ -846,7 +635,7 @@ fn directory_moved_to_trash() -> anyhow::Result<()> {
         .system_file(sub_path.join("a.py"))
         .expect("a.py to exist");
 
-    case.assert_indexed_project_files([bar, init_file, a_file]);
+    assert_eq!(case.collect_project_files(), &[bar, init_file, a_file]);
 
     std::fs::create_dir(case.root_path().join(".trash").as_std_path())?;
     let trashed_sub = case.root_path().join(".trash/sub");
@@ -867,7 +656,7 @@ fn directory_moved_to_trash() -> anyhow::Result<()> {
     assert!(!init_file.exists(case.db()));
     assert!(!a_file.exists(case.db()));
 
-    case.assert_indexed_project_files([bar]);
+    assert_eq!(case.collect_project_files(), &[bar]);
 
     Ok(())
 }
@@ -901,7 +690,7 @@ fn directory_renamed() -> anyhow::Result<()> {
         .system_file(sub_path.join("a.py"))
         .expect("a.py to exist");
 
-    case.assert_indexed_project_files([bar, sub_init, sub_a]);
+    assert_eq!(case.collect_project_files(), &[bar, sub_init, sub_a]);
 
     let foo_baz = case.project_path("foo/baz");
 
@@ -943,7 +732,10 @@ fn directory_renamed() -> anyhow::Result<()> {
     assert!(foo_baz_init.exists(case.db()));
     assert!(foo_baz_a.exists(case.db()));
 
-    case.assert_indexed_project_files([bar, foo_baz_init, foo_baz_a]);
+    assert_eq!(
+        case.collect_project_files(),
+        &[bar, foo_baz_init, foo_baz_a]
+    );
 
     Ok(())
 }
@@ -972,7 +764,7 @@ fn directory_deleted() -> anyhow::Result<()> {
     let a_file = case
         .system_file(sub_path.join("a.py"))
         .expect("a.py to exist");
-    case.assert_indexed_project_files([bar, init_file, a_file]);
+    assert_eq!(case.collect_project_files(), &[bar, init_file, a_file]);
 
     std::fs::remove_dir_all(sub_path.as_std_path())
         .with_context(|| "Failed to remove the sub directory")?;
@@ -990,26 +782,21 @@ fn directory_deleted() -> anyhow::Result<()> {
 
     assert!(!init_file.exists(case.db()));
     assert!(!a_file.exists(case.db()));
-    case.assert_indexed_project_files([bar]);
+    assert_eq!(case.collect_project_files(), &[bar]);
 
     Ok(())
 }
 
 #[test]
 fn search_path() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        context.write_project_file("bar.py", "import sub.a")?;
-
-        context.set_options(Options {
+    let mut case = setup_with_options([("bar.py", "import sub.a")], |root_path, _project_path| {
+        Some(Options {
             environment: Some(EnvironmentOptions {
-                extra_paths: Some(vec![RelativePathBuf::cli(
-                    context.join_root_path("site_packages"),
-                )]),
+                extra_paths: Some(vec![RelativePathBuf::cli(root_path.join("site_packages"))]),
                 ..EnvironmentOptions::default()
             }),
             ..Options::default()
-        });
-        Ok(())
+        })
     })?;
 
     let site_packages = case.root_path().join("site_packages");
@@ -1026,7 +813,10 @@ fn search_path() -> anyhow::Result<()> {
     case.apply_changes(changes);
 
     assert!(resolve_module(case.db().upcast(), &ModuleName::new_static("a").unwrap()).is_some());
-    case.assert_indexed_project_files([case.system_file(case.project_path("bar.py")).unwrap()]);
+    assert_eq!(
+        case.collect_project_files(),
+        &[case.system_file(case.project_path("bar.py")).unwrap()]
+    );
 
     Ok(())
 }
@@ -1063,19 +853,14 @@ fn add_search_path() -> anyhow::Result<()> {
 
 #[test]
 fn remove_search_path() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        context.write_project_file("bar.py", "import sub.a")?;
-        context.set_options(Options {
+    let mut case = setup_with_options([("bar.py", "import sub.a")], |root_path, _project_path| {
+        Some(Options {
             environment: Some(EnvironmentOptions {
-                extra_paths: Some(vec![RelativePathBuf::cli(
-                    context.join_root_path("site_packages"),
-                )]),
+                extra_paths: Some(vec![RelativePathBuf::cli(root_path.join("site_packages"))]),
                 ..EnvironmentOptions::default()
             }),
             ..Options::default()
-        });
-
-        Ok(())
+        })
     })?;
 
     // Remove site packages from the search path settings.
@@ -1098,30 +883,30 @@ fn remove_search_path() -> anyhow::Result<()> {
 
 #[test]
 fn change_python_version_and_platform() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
+    let mut case = setup_with_options(
         // `sys.last_exc` is a Python 3.12 only feature
         // `os.getegid()` is Unix only
-        context.write_project_file(
+        [(
             "bar.py",
             r#"
 import sys
 import os
 print(sys.last_exc, os.getegid())
 "#,
-        )?;
-        context.set_options(Options {
-            environment: Some(EnvironmentOptions {
-                python_version: Some(RangedValue::cli(PythonVersion::PY311)),
-                python_platform: Some(RangedValue::cli(PythonPlatform::Identifier(
-                    "win32".to_string(),
-                ))),
-                ..EnvironmentOptions::default()
-            }),
-            ..Options::default()
-        });
-
-        Ok(())
-    })?;
+        )],
+        |_root_path, _project_path| {
+            Some(Options {
+                environment: Some(EnvironmentOptions {
+                    python_version: Some(RangedValue::cli(PythonVersion::PY311)),
+                    python_platform: Some(RangedValue::cli(PythonPlatform::Identifier(
+                        "win32".to_string(),
+                    ))),
+                    ..EnvironmentOptions::default()
+                }),
+                ..Options::default()
+            })
+        },
+    )?;
 
     let diagnostics = case.db.check().context("Failed to check project.")?;
 
@@ -1156,35 +941,28 @@ print(sys.last_exc, os.getegid())
 
 #[test]
 fn changed_versions_file() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        std::fs::write(
-            context.join_project_path("bar.py").as_std_path(),
-            "import sub.a",
-        )?;
-        std::fs::create_dir_all(context.join_root_path("typeshed/stdlib").as_std_path())?;
-        std::fs::write(
-            context
-                .join_root_path("typeshed/stdlib/VERSIONS")
-                .as_std_path(),
-            "",
-        )?;
-        std::fs::write(
-            context
-                .join_root_path("typeshed/stdlib/os.pyi")
-                .as_std_path(),
-            "# not important",
-        )?;
+    let mut case = setup_with_options(
+        |root_path: &SystemPath, project_path: &SystemPath| {
+            std::fs::write(project_path.join("bar.py").as_std_path(), "import sub.a")?;
+            std::fs::create_dir_all(root_path.join("typeshed/stdlib").as_std_path())?;
+            std::fs::write(root_path.join("typeshed/stdlib/VERSIONS").as_std_path(), "")?;
+            std::fs::write(
+                root_path.join("typeshed/stdlib/os.pyi").as_std_path(),
+                "# not important",
+            )?;
 
-        context.set_options(Options {
-            environment: Some(EnvironmentOptions {
-                typeshed: Some(RelativePathBuf::cli(context.join_root_path("typeshed"))),
-                ..EnvironmentOptions::default()
-            }),
-            ..Options::default()
-        });
-
-        Ok(())
-    })?;
+            Ok(())
+        },
+        |root_path, _project_path| {
+            Some(Options {
+                environment: Some(EnvironmentOptions {
+                    typeshed: Some(RelativePathBuf::cli(root_path.join("typeshed"))),
+                    ..EnvironmentOptions::default()
+                }),
+                ..Options::default()
+            })
+        },
+    )?;
 
     // Unset the custom typeshed directory.
     assert_eq!(
@@ -1229,12 +1007,12 @@ fn changed_versions_file() -> anyhow::Result<()> {
 /// we're seeing is that Windows only emits a single event, similar to Linux.
 #[test]
 fn hard_links_in_project() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        let foo_path = context.join_project_path("foo.py");
+    let mut case = setup(|_root: &SystemPath, project: &SystemPath| {
+        let foo_path = project.join("foo.py");
         std::fs::write(foo_path.as_std_path(), "print('Version 1')")?;
 
         // Create a hardlink to `foo`
-        let bar_path = context.join_project_path("bar.py");
+        let bar_path = project.join("bar.py");
         std::fs::hard_link(foo_path.as_std_path(), bar_path.as_std_path())
             .context("Failed to create hard link from foo.py -> bar.py")?;
 
@@ -1248,7 +1026,6 @@ fn hard_links_in_project() -> anyhow::Result<()> {
 
     assert_eq!(source_text(case.db(), foo).as_str(), "print('Version 1')");
     assert_eq!(source_text(case.db(), bar).as_str(), "print('Version 1')");
-    case.assert_indexed_project_files([bar, foo]);
 
     // Write to the hard link target.
     update_file(foo_path, "print('Version 2')").context("Failed to update foo.py")?;
@@ -1301,12 +1078,12 @@ fn hard_links_in_project() -> anyhow::Result<()> {
     ignore = "windows doesn't support observing changes to hard linked files."
 )]
 fn hard_links_to_target_outside_project() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
-        let foo_path = context.join_root_path("foo.py");
+    let mut case = setup(|root: &SystemPath, project: &SystemPath| {
+        let foo_path = root.join("foo.py");
         std::fs::write(foo_path.as_std_path(), "print('Version 1')")?;
 
         // Create a hardlink to `foo`
-        let bar_path = context.join_project_path("bar.py");
+        let bar_path = project.join("bar.py");
         std::fs::hard_link(foo_path.as_std_path(), bar_path.as_std_path())
             .context("Failed to create hard link from foo.py -> bar.py")?;
 
@@ -1409,9 +1186,9 @@ mod unix {
         ignore = "FSEvents doesn't emit change events for symlinked directories outside of the watched paths."
     )]
     fn symlink_target_outside_watched_paths() -> anyhow::Result<()> {
-        let mut case = setup(|context: &mut SetupContext| {
+        let mut case = setup(|root: &SystemPath, project: &SystemPath| {
             // Set up the symlink target.
-            let link_target = context.join_root_path("bar");
+            let link_target = root.join("bar");
             std::fs::create_dir_all(link_target.as_std_path())
                 .context("Failed to create link target directory")?;
             let baz_original = link_target.join("baz.py");
@@ -1419,7 +1196,7 @@ mod unix {
                 .context("Failed to write link target file")?;
 
             // Create a symlink inside the project
-            let bar = context.join_project_path("bar");
+            let bar = project.join("bar");
             std::os::unix::fs::symlink(link_target.as_std_path(), bar.as_std_path())
                 .context("Failed to create symlink to bar package")?;
 
@@ -1490,9 +1267,9 @@ mod unix {
     /// ```
     #[test]
     fn symlink_inside_project() -> anyhow::Result<()> {
-        let mut case = setup(|context: &mut SetupContext| {
+        let mut case = setup(|_root: &SystemPath, project: &SystemPath| {
             // Set up the symlink target.
-            let link_target = context.join_project_path("patched/bar");
+            let link_target = project.join("patched/bar");
             std::fs::create_dir_all(link_target.as_std_path())
                 .context("Failed to create link target directory")?;
             let baz_original = link_target.join("baz.py");
@@ -1500,7 +1277,7 @@ mod unix {
                 .context("Failed to write link target file")?;
 
             // Create a symlink inside site-packages
-            let bar_in_project = context.join_project_path("bar");
+            let bar_in_project = project.join("bar");
             std::os::unix::fs::symlink(link_target.as_std_path(), bar_in_project.as_std_path())
                 .context("Failed to create symlink to bar package")?;
 
@@ -1528,8 +1305,6 @@ mod unix {
         );
         assert_eq!(baz.file().path(case.db()).as_system_path(), Some(&*bar_baz));
 
-        case.assert_indexed_project_files([patched_bar_baz_file]);
-
         // Write to the symlink target.
         update_file(&patched_bar_baz, "def baz(): print('Version 2')")
             .context("Failed to update bar/baz.py")?;
@@ -1565,7 +1340,6 @@ mod unix {
             bar_baz_text = bar_baz_text.as_str()
         );
 
-        case.assert_indexed_project_files([patched_bar_baz_file]);
         Ok(())
     }
 
@@ -1583,39 +1357,42 @@ mod unix {
     /// ```
     #[test]
     fn symlinked_module_search_path() -> anyhow::Result<()> {
-        let mut case = setup(|context: &mut SetupContext| {
-            // Set up the symlink target.
-            let site_packages = context.join_root_path("site-packages");
-            let bar = site_packages.join("bar");
-            std::fs::create_dir_all(bar.as_std_path()).context("Failed to create bar directory")?;
-            let baz_original = bar.join("baz.py");
-            std::fs::write(baz_original.as_std_path(), "def baz(): ...")
-                .context("Failed to write baz.py")?;
+        let mut case = setup_with_options(
+            |root: &SystemPath, project: &SystemPath| {
+                // Set up the symlink target.
+                let site_packages = root.join("site-packages");
+                let bar = site_packages.join("bar");
+                std::fs::create_dir_all(bar.as_std_path())
+                    .context("Failed to create bar directory")?;
+                let baz_original = bar.join("baz.py");
+                std::fs::write(baz_original.as_std_path(), "def baz(): ...")
+                    .context("Failed to write baz.py")?;
 
-            // Symlink the site packages in the venv to the global site packages
-            let venv_site_packages =
-                context.join_project_path(".venv/lib/python3.12/site-packages");
-            std::fs::create_dir_all(venv_site_packages.parent().unwrap())
-                .context("Failed to create .venv directory")?;
-            std::os::unix::fs::symlink(
-                site_packages.as_std_path(),
-                venv_site_packages.as_std_path(),
-            )
-            .context("Failed to create symlink to site-packages")?;
+                // Symlink the site packages in the venv to the global site packages
+                let venv_site_packages = project.join(".venv/lib/python3.12/site-packages");
+                std::fs::create_dir_all(venv_site_packages.parent().unwrap())
+                    .context("Failed to create .venv directory")?;
+                std::os::unix::fs::symlink(
+                    site_packages.as_std_path(),
+                    venv_site_packages.as_std_path(),
+                )
+                .context("Failed to create symlink to site-packages")?;
 
-            context.set_options(Options {
-                environment: Some(EnvironmentOptions {
-                    extra_paths: Some(vec![RelativePathBuf::cli(
-                        ".venv/lib/python3.12/site-packages",
-                    )]),
-                    python_version: Some(RangedValue::cli(PythonVersion::PY312)),
-                    ..EnvironmentOptions::default()
-                }),
-                ..Options::default()
-            });
-
-            Ok(())
-        })?;
+                Ok(())
+            },
+            |_root, _project| {
+                Some(Options {
+                    environment: Some(EnvironmentOptions {
+                        extra_paths: Some(vec![RelativePathBuf::cli(
+                            ".venv/lib/python3.12/site-packages",
+                        )]),
+                        python_version: Some(RangedValue::cli(PythonVersion::PY312)),
+                        ..EnvironmentOptions::default()
+                    }),
+                    ..Options::default()
+                })
+            },
+        )?;
 
         let baz = resolve_module(
             case.db().upcast(),
@@ -1642,8 +1419,6 @@ mod unix {
             Some(&*baz_original)
         );
 
-        case.assert_indexed_project_files([]);
-
         // Write to the symlink target.
         update_file(&baz_original, "def baz(): print('Version 2')")
             .context("Failed to update bar/baz.py")?;
@@ -1669,17 +1444,15 @@ mod unix {
             "def baz(): print('Version 2')"
         );
 
-        case.assert_indexed_project_files([]);
-
         Ok(())
     }
 }
 
 #[test]
 fn nested_projects_delete_root() -> anyhow::Result<()> {
-    let mut case = setup(|context: &mut SetupContext| {
+    let mut case = setup(|root: &SystemPath, project_root: &SystemPath| {
         std::fs::write(
-            context.join_project_path("pyproject.toml").as_std_path(),
+            project_root.join("pyproject.toml").as_std_path(),
             r#"
             [project]
             name = "inner"
@@ -1689,7 +1462,7 @@ fn nested_projects_delete_root() -> anyhow::Result<()> {
         )?;
 
         std::fs::write(
-            context.join_root_path("pyproject.toml").as_std_path(),
+            root.join("pyproject.toml").as_std_path(),
             r#"
             [project]
             name = "outer"
@@ -1714,79 +1487,3 @@ fn nested_projects_delete_root() -> anyhow::Result<()> {
 
     Ok(())
 }
-
-#[test]
-fn changes_to_user_configuration() -> anyhow::Result<()> {
-    let mut _config_dir_override: Option<UserConfigDirectoryOverrideGuard> = None;
-
-    let mut case = setup(|context: &mut SetupContext| {
-        std::fs::write(
-            context.join_project_path("pyproject.toml").as_std_path(),
-            r#"
-            [project]
-            name = "test"
-            "#,
-        )?;
-
-        std::fs::write(
-            context.join_project_path("foo.py").as_std_path(),
-            "a = 10 / 0",
-        )?;
-
-        let config_directory = context.join_root_path("home/.config");
-        std::fs::create_dir_all(config_directory.join("knot").as_std_path())?;
-        std::fs::write(
-            config_directory.join("knot/knot.toml").as_std_path(),
-            r#"
-            [rules]
-            division-by-zero = "ignore"
-            "#,
-        )?;
-
-        _config_dir_override = Some(
-            context
-                .system()
-                .with_user_config_directory(Some(config_directory)),
-        );
-
-        Ok(())
-    })?;
-
-    let foo = case
-        .system_file(case.project_path("foo.py"))
-        .expect("foo.py to exist");
-    let diagnostics = case
-        .db()
-        .check_file(foo)
-        .context("Failed to check project.")?;
-
-    assert!(
-        diagnostics.is_empty(),
-        "Expected no diagnostics but got: {diagnostics:#?}"
-    );
-
-    // Enable division-by-zero in the user configuration with warning severity
-    update_file(
-        case.root_path().join("home/.config/knot/knot.toml"),
-        r#"
-        [rules]
-        division-by-zero = "warn"
-        "#,
-    )?;
-
-    let changes = case.stop_watch(event_for_file("knot.toml"));
-
-    case.apply_changes(changes);
-
-    let diagnostics = case
-        .db()
-        .check_file(foo)
-        .context("Failed to check project.")?;
-
-    assert!(
-        diagnostics.len() == 1,
-        "Expected exactly one diagnostic but got: {diagnostics:#?}"
-    );
-
-    Ok(())
-}

crates/red_knot_project/Cargo.toml

@@ -13,7 +13,7 @@ license.workspace = true
 
 [dependencies]
 ruff_cache = { workspace = true }
-ruff_db = { workspace = true, features = ["cache", "serde"] }
+ruff_db = { workspace = true, features = ["os", "cache", "serde"] }
 ruff_macros = { workspace = true }
 ruff_python_ast = { workspace = true, features = ["serde"] }
 ruff_text_size = { workspace = true }
@@ -24,11 +24,10 @@ anyhow = { workspace = true }
 crossbeam = { workspace = true }
 glob = { workspace = true }
 notify = { workspace = true }
-pep440_rs = { workspace = true, features = ["version-ranges"] }
+pep440_rs = { workspace = true }
 rayon = { workspace = true }
 rustc-hash = { workspace = true }
 salsa = { workspace = true }
-schemars = { workspace = true, optional = true }
 serde = { workspace = true }
 thiserror = { workspace = true }
 toml = { workspace = true }
@@ -41,9 +40,8 @@ insta = { workspace = true, features = ["redactions", "ron"] }
 
 [features]
 default = ["zstd"]
-deflate = ["red_knot_vendored/deflate"]
-schemars = ["dep:schemars", "ruff_db/schemars", "red_knot_python_semantic/schemars"]
 zstd = ["red_knot_vendored/zstd"]
+deflate = ["red_knot_vendored/deflate"]
 
 [lints]
 workspace = true

crates/red_knot_project/src/combine.rs

@@ -1,8 +1,7 @@
 use std::{collections::HashMap, hash::BuildHasher};
 
-use red_knot_python_semantic::{PythonPath, PythonPlatform};
+use red_knot_python_semantic::{PythonPlatform, PythonVersion, SitePackages};
 use ruff_db::system::SystemPathBuf;
-use ruff_python_ast::PythonVersion;
 
 /// Combine two values, preferring the values in `self`.
 ///
@@ -128,7 +127,7 @@ macro_rules! impl_noop_combine {
 
 impl_noop_combine!(SystemPathBuf);
 impl_noop_combine!(PythonPlatform);
-impl_noop_combine!(PythonPath);
+impl_noop_combine!(SitePackages);
 impl_noop_combine!(PythonVersion);
 
 // std types

crates/red_knot_project/src/db.rs

@@ -5,7 +5,7 @@ use crate::DEFAULT_LINT_REGISTRY;
 use crate::{Project, ProjectMetadata};
 use red_knot_python_semantic::lint::{LintRegistry, RuleSelection};
 use red_knot_python_semantic::{Db as SemanticDb, Program};
-use ruff_db::diagnostic::OldDiagnosticTrait;
+use ruff_db::diagnostic::Diagnostic;
 use ruff_db::files::{File, Files};
 use ruff_db::system::System;
 use ruff_db::vendored::VendoredFileSystem;
@@ -55,11 +55,11 @@ impl ProjectDatabase {
     }
 
     /// Checks all open files in the project and its dependencies.
-    pub fn check(&self) -> Result<Vec<Box<dyn OldDiagnosticTrait>>, Cancelled> {
+    pub fn check(&self) -> Result<Vec<Box<dyn Diagnostic>>, Cancelled> {
         self.with_db(|db| db.project().check(db))
     }
 
-    pub fn check_file(&self, file: File) -> Result<Vec<Box<dyn OldDiagnosticTrait>>, Cancelled> {
+    pub fn check_file(&self, file: File) -> Result<Vec<Box<dyn Diagnostic>>, Cancelled> {
         let _span = tracing::debug_span!("check_file", file=%file.path(self)).entered();
 
         self.with_db(|db| self.project().check_file(db, file))
@@ -114,8 +114,8 @@ impl SemanticDb for ProjectDatabase {
         project.is_file_open(self, file)
     }
 
-    fn rule_selection(&self) -> Arc<RuleSelection> {
-        self.project().rules(self)
+    fn rule_selection(&self) -> &RuleSelection {
+        self.project().rule_selection(self)
     }
 
     fn lint_registry(&self) -> &LintRegistry {
@@ -186,6 +186,7 @@ pub(crate) mod tests {
         files: Files,
         system: TestSystem,
         vendored: VendoredFileSystem,
+        rule_selection: RuleSelection,
         project: Option<Project>,
     }
 
@@ -197,6 +198,7 @@ pub(crate) mod tests {
                 vendored: red_knot_vendored::file_system().clone(),
                 files: Files::default(),
                 events: Arc::default(),
+                rule_selection: RuleSelection::from_registry(&DEFAULT_LINT_REGISTRY),
                 project: None,
             };
 
@@ -268,8 +270,8 @@ pub(crate) mod tests {
             !file.path(self).is_vendored_path()
         }
 
-        fn rule_selection(&self) -> Arc<RuleSelection> {
-            self.project().rules(self)
+        fn rule_selection(&self) -> &RuleSelection {
+            &self.rule_selection
         }
 
         fn lint_registry(&self) -> &LintRegistry {

crates/red_knot_project/src/db/changes.rs

@@ -2,11 +2,10 @@ use crate::db::{Db, ProjectDatabase};
 use crate::metadata::options::Options;
 use crate::watch::{ChangeEvent, CreatedKind, DeletedKind};
 use crate::{Project, ProjectMetadata};
-use std::collections::BTreeSet;
 
-use crate::walk::ProjectFilesWalker;
 use red_knot_python_semantic::Program;
-use ruff_db::files::{File, Files};
+use ruff_db::files::{system_path_to_file, File, Files};
+use ruff_db::system::walk_directory::WalkState;
 use ruff_db::system::SystemPath;
 use ruff_db::Db as _;
 use rustc_hash::FxHashSet;
@@ -15,7 +14,7 @@ impl ProjectDatabase {
     #[tracing::instrument(level = "debug", skip(self, changes, cli_options))]
     pub fn apply_changes(&mut self, changes: Vec<ChangeEvent>, cli_options: Option<&Options>) {
         let mut project = self.project();
-        let project_root = project.root(self).to_path_buf();
+        let project_path = project.root(self).to_path_buf();
         let program = Program::get(self);
         let custom_stdlib_versions_path = program
             .custom_stdlib_search_path(self)
@@ -30,7 +29,7 @@ impl ProjectDatabase {
 
         // Deduplicate the `sync` calls. Many file watchers emit multiple events for the same path.
         let mut synced_files = FxHashSet::default();
-        let mut sync_recursively = BTreeSet::default();
+        let mut synced_recursively = FxHashSet::default();
 
         let mut sync_path = |db: &mut ProjectDatabase, path: &SystemPath| {
             if synced_files.insert(path.to_path_buf()) {
@@ -38,13 +37,17 @@ impl ProjectDatabase {
             }
         };
 
-        for change in changes {
-            tracing::trace!("Handle change: {:?}", change);
+        let mut sync_recursively = |db: &mut ProjectDatabase, path: &SystemPath| {
+            if synced_recursively.insert(path.to_path_buf()) {
+                Files::sync_recursively(db, path);
+            }
+        };
 
+        for change in changes {
             if let Some(path) = change.system_path() {
                 if matches!(
                     path.file_name(),
-                    Some(".gitignore" | ".ignore" | "knot.toml" | "pyproject.toml")
+                    Some(".gitignore" | ".ignore" | "ruff.toml" | ".ruff.toml" | "pyproject.toml")
                 ) {
                     // Changes to ignore files or settings can change the project structure or add/remove files.
                     project_changed = true;
@@ -66,27 +69,16 @@ impl ProjectDatabase {
                     match kind {
                         CreatedKind::File => sync_path(self, &path),
                         CreatedKind::Directory | CreatedKind::Any => {
-                            sync_recursively.insert(path.clone());
+                            sync_recursively(self, &path);
                         }
                     }
 
-                    // Unlike other files, it's not only important to update the status of existing
-                    // and known `File`s (`sync_recursively`), it's also important to discover new files
-                    // that were added in the project's root (or any of the paths included for checking).
-                    //
-                    // This is important because `Project::check` iterates over all included files.
-                    // The code below walks the `added_paths` and adds all files that
-                    // should be included in the project. We can skip this check for
-                    // paths that aren't part of the project or shouldn't be included
-                    // when checking the project.
-                    if project.is_path_included(self, &path) {
-                        if self.system().is_file(&path) {
-                            // Add the parent directory because `walkdir` always visits explicitly passed files
-                            // even if they match an exclude filter.
-                            added_paths.insert(path.parent().unwrap().to_path_buf());
-                        } else {
-                            added_paths.insert(path);
-                        }
+                    if self.system().is_file(&path) {
+                        // Add the parent directory because `walkdir` always visits explicitly passed files
+                        // even if they match an exclude filter.
+                        added_paths.insert(path.parent().unwrap().to_path_buf());
+                    } else {
+                        added_paths.insert(path);
                     }
                 }
 
@@ -110,7 +102,7 @@ impl ProjectDatabase {
                             project.remove_file(self, file);
                         }
                     } else {
-                        sync_recursively.insert(path.clone());
+                        sync_recursively(self, &path);
 
                         if custom_stdlib_versions_path
                             .as_ref()
@@ -119,19 +111,11 @@ impl ProjectDatabase {
                             custom_stdlib_change = true;
                         }
 
-                        if project.is_path_included(self, &path) || path == project_root {
-                            // TODO: Shouldn't it be enough to simply traverse the project files and remove all
-                            // that start with the given path?
-                            tracing::debug!(
-                                "Reload project because of a path that could have been a directory."
-                            );
-
-                            // Perform a full-reload in case the deleted directory contained the pyproject.toml.
-                            // We may want to make this more clever in the future, to e.g. iterate over the
-                            // indexed files and remove the once that start with the same path, unless
-                            // the deleted path is the project configuration.
-                            project_changed = true;
-                        }
+                        // Perform a full-reload in case the deleted directory contained the pyproject.toml.
+                        // We may want to make this more clever in the future, to e.g. iterate over the
+                        // indexed files and remove the once that start with the same path, unless
+                        // the deleted path is the project configuration.
+                        project_changed = true;
                     }
                 }
 
@@ -148,40 +132,18 @@ impl ProjectDatabase {
                 ChangeEvent::Rescan => {
                     project_changed = true;
                     Files::sync_all(self);
-                    sync_recursively.clear();
                     break;
                 }
             }
         }
 
-        let sync_recursively = sync_recursively.into_iter();
-        let mut last = None;
-
-        for path in sync_recursively {
-            // Avoid re-syncing paths that are sub-paths of each other.
-            if let Some(last) = &last {
-                if path.starts_with(last) {
-                    continue;
-                }
-            }
-
-            Files::sync_recursively(self, &path);
-            last = Some(path);
-        }
-
         if project_changed {
-            match ProjectMetadata::discover(&project_root, self.system()) {
+            match ProjectMetadata::discover(&project_path, self.system()) {
                 Ok(mut metadata) => {
                     if let Some(cli_options) = cli_options {
                         metadata.apply_cli_options(cli_options.clone());
                     }
 
-                    if let Err(error) = metadata.apply_configuration_files(self.system()) {
-                        tracing::error!(
-                            "Failed to apply configuration files, continuing without applying them: {error}"
-                        );
-                    }
-
                     let program_settings = metadata.to_program_settings(self.system());
 
                     let program = Program::get(self);
@@ -217,24 +179,43 @@ impl ProjectDatabase {
             }
         }
 
-        let diagnostics = if let Some(walker) = ProjectFilesWalker::incremental(self, added_paths) {
-            // Use directory walking to discover newly added files.
-            let (files, diagnostics) = walker.collect_vec(self);
+        let mut added_paths = added_paths.into_iter();
 
-            for file in files {
-                project.add_file(self, file);
+        // Use directory walking to discover newly added files.
+        if let Some(path) = added_paths.next() {
+            let mut walker = self.system().walk_directory(&path);
+
+            for extra_path in added_paths {
+                walker = walker.add(&extra_path);
             }
 
-            diagnostics
-        } else {
-            Vec::new()
-        };
+            let added_paths = std::sync::Mutex::new(Vec::default());
 
-        // Note: We simply replace all IO related diagnostics here. This isn't ideal, because
-        // it removes IO errors that may still be relevant. However, tracking IO errors correctly
-        // across revisions doesn't feel essential, considering that they're rare. However, we could
-        // implement a `BTreeMap` or similar and only prune the diagnostics from paths that we've
-        // re-scanned (or that were removed etc).
-        project.replace_index_diagnostics(self, diagnostics);
+            walker.run(|| {
+                Box::new(|entry| {
+                    let Ok(entry) = entry else {
+                        return WalkState::Continue;
+                    };
+
+                    if !entry.file_type().is_file() {
+                        return WalkState::Continue;
+                    }
+
+                    let mut paths = added_paths.lock().unwrap();
+
+                    paths.push(entry.into_path());
+
+                    WalkState::Continue
+                })
+            });
+
+            for path in added_paths.into_inner().unwrap() {
+                let file = system_path_to_file(self, &path);
+
+                if let Ok(file) = file {
+                    project.add_file(self, file);
+                }
+            }
+        }
     }
 }

crates/red_knot_project/src/files.rs

@@ -8,7 +8,10 @@ use salsa::Setter;
 use ruff_db::files::File;
 
 use crate::db::Db;
-use crate::{IOErrorDiagnostic, Project};
+use crate::Project;
+
+/// Cheap cloneable hash set of files.
+type FileSet = Arc<FxHashSet<File>>;
 
 /// The indexed files of a project.
 ///
@@ -32,9 +35,9 @@ impl IndexedFiles {
         }
     }
 
-    fn indexed(inner: Arc<IndexedInner>) -> Self {
+    fn indexed(files: FileSet) -> Self {
         Self {
-            state: std::sync::Mutex::new(State::Indexed(inner)),
+            state: std::sync::Mutex::new(State::Indexed(files)),
         }
     }
 
@@ -43,8 +46,8 @@ impl IndexedFiles {
 
         match &*state {
             State::Lazy => Index::Lazy(LazyFiles { files: state }),
-            State::Indexed(inner) => Index::Indexed(Indexed {
-                inner: Arc::clone(inner),
+            State::Indexed(files) => Index::Indexed(Indexed {
+                files: Arc::clone(files),
                 _lifetime: PhantomData,
             }),
         }
@@ -91,7 +94,7 @@ impl IndexedFiles {
         Some(IndexedMut {
             db: Some(db),
             project,
-            indexed,
+            files: indexed,
             did_change: false,
         })
     }
@@ -109,7 +112,7 @@ enum State {
     Lazy,
 
     /// The files are indexed. Stores the known files of a package.
-    Indexed(Arc<IndexedInner>),
+    Indexed(FileSet),
 }
 
 pub(super) enum Index<'db> {
@@ -126,48 +129,32 @@ pub(super) struct LazyFiles<'db> {
 
 impl<'db> LazyFiles<'db> {
     /// Sets the indexed files of a package to `files`.
-    pub(super) fn set(
-        mut self,
-        files: FxHashSet<File>,
-        diagnostics: Vec<IOErrorDiagnostic>,
-    ) -> Indexed<'db> {
+    pub(super) fn set(mut self, files: FxHashSet<File>) -> Indexed<'db> {
         let files = Indexed {
-            inner: Arc::new(IndexedInner { files, diagnostics }),
+            files: Arc::new(files),
             _lifetime: PhantomData,
         };
-        *self.files = State::Indexed(Arc::clone(&files.inner));
+        *self.files = State::Indexed(Arc::clone(&files.files));
         files
     }
 }
 
-/// The indexed files of the project.
+/// The indexed files of a package.
 ///
 /// Note: This type is intentionally non-cloneable. Making it cloneable requires
 /// revisiting the locking behavior in [`IndexedFiles::indexed_mut`].
-#[derive(Debug)]
+#[derive(Debug, PartialEq, Eq)]
 pub struct Indexed<'db> {
-    inner: Arc<IndexedInner>,
+    files: FileSet,
     // Preserve the lifetime of `PackageFiles`.
     _lifetime: PhantomData<&'db ()>,
 }
 
-#[derive(Debug)]
-struct IndexedInner {
-    files: FxHashSet<File>,
-    diagnostics: Vec<IOErrorDiagnostic>,
-}
-
-impl Indexed<'_> {
-    pub(super) fn diagnostics(&self) -> &[IOErrorDiagnostic] {
-        &self.inner.diagnostics
-    }
-}
-
 impl Deref for Indexed<'_> {
     type Target = FxHashSet<File>;
 
     fn deref(&self) -> &Self::Target {
-        &self.inner.files
+        &self.files
     }
 }
 
@@ -178,7 +165,7 @@ impl<'a> IntoIterator for &'a Indexed<'_> {
     type IntoIter = IndexedIter<'a>;
 
     fn into_iter(self) -> Self::IntoIter {
-        self.inner.files.iter().copied()
+        self.files.iter().copied()
     }
 }
 
@@ -189,13 +176,13 @@ impl<'a> IntoIterator for &'a Indexed<'_> {
 pub(super) struct IndexedMut<'db> {
     db: Option<&'db mut dyn Db>,
     project: Project,
-    indexed: Arc<IndexedInner>,
+    files: FileSet,
     did_change: bool,
 }
 
 impl IndexedMut<'_> {
     pub(super) fn insert(&mut self, file: File) -> bool {
-        if self.inner_mut().files.insert(file) {
+        if self.files_mut().insert(file) {
             self.did_change = true;
             true
         } else {
@@ -204,7 +191,7 @@ impl IndexedMut<'_> {
     }
 
     pub(super) fn remove(&mut self, file: File) -> bool {
-        if self.inner_mut().files.remove(&file) {
+        if self.files_mut().remove(&file) {
             self.did_change = true;
             true
         } else {
@@ -212,13 +199,8 @@ impl IndexedMut<'_> {
         }
     }
 
-    pub(super) fn set_diagnostics(&mut self, diagnostics: Vec<IOErrorDiagnostic>) {
-        self.inner_mut().diagnostics = diagnostics;
-    }
-
-    fn inner_mut(&mut self) -> &mut IndexedInner {
-        Arc::get_mut(&mut self.indexed)
-            .expect("All references to `FilesSet` should have been dropped")
+    fn files_mut(&mut self) -> &mut FxHashSet<File> {
+        Arc::get_mut(&mut self.files).expect("All references to `FilesSet` to have been dropped")
     }
 
     fn set_impl(&mut self) {
@@ -226,16 +208,16 @@ impl IndexedMut<'_> {
             return;
         };
 
-        let indexed = Arc::clone(&self.indexed);
+        let files = Arc::clone(&self.files);
 
         if self.did_change {
             // If there are changes, set the new file_set to trigger a salsa revision change.
             self.project
                 .set_file_set(db)
-                .to(IndexedFiles::indexed(indexed));
+                .to(IndexedFiles::indexed(files));
         } else {
             // The `indexed_mut` replaced the `state` with Lazy. Restore it back to the indexed state.
-            *self.project.file_set(db).state.lock().unwrap() = State::Indexed(indexed);
+            *self.project.file_set(db).state.lock().unwrap() = State::Indexed(files);
         }
     }
 }
@@ -255,7 +237,7 @@ mod tests {
     use crate::files::Index;
     use crate::ProjectMetadata;
     use ruff_db::files::system_path_to_file;
-    use ruff_db::system::{DbWithWritableSystem as _, SystemPathBuf};
+    use ruff_db::system::{DbWithTestSystem, SystemPathBuf};
     use ruff_python_ast::name::Name;
 
     #[test]
@@ -270,7 +252,7 @@ mod tests {
         let file = system_path_to_file(&db, "test.py").unwrap();
 
         let files = match project.file_set(&db).get() {
-            Index::Lazy(lazy) => lazy.set(FxHashSet::from_iter([file]), Vec::new()),
+            Index::Lazy(lazy) => lazy.set(FxHashSet::from_iter([file])),
             Index::Indexed(files) => files,
         };
 

crates/red_knot_project/src/lib.rs

@@ -1,32 +1,31 @@
 #![allow(clippy::ref_option)]
 
 use crate::metadata::options::OptionDiagnostic;
-use crate::walk::{ProjectFilesFilter, ProjectFilesWalker};
 pub use db::{Db, ProjectDatabase};
 use files::{Index, Indexed, IndexedFiles};
-use metadata::settings::Settings;
 pub use metadata::{ProjectDiscoveryError, ProjectMetadata};
 use red_knot_python_semantic::lint::{LintRegistry, LintRegistryBuilder, RuleSelection};
 use red_knot_python_semantic::register_lints;
 use red_knot_python_semantic::types::check_types;
-use ruff_db::diagnostic::{DiagnosticId, OldDiagnosticTrait, OldParseDiagnostic, Severity, Span};
-use ruff_db::files::File;
+use ruff_db::diagnostic::{Diagnostic, DiagnosticId, ParseDiagnostic, Severity};
+use ruff_db::files::{system_path_to_file, File};
 use ruff_db::parsed::parsed_module;
 use ruff_db::source::{source_text, SourceTextError};
-use ruff_db::system::{SystemPath, SystemPathBuf};
-use rustc_hash::FxHashSet;
+use ruff_db::system::walk_directory::WalkState;
+use ruff_db::system::{FileType, SystemPath};
+use ruff_python_ast::PySourceType;
+use ruff_text_size::TextRange;
+use rustc_hash::{FxBuildHasher, FxHashSet};
 use salsa::Durability;
 use salsa::Setter;
 use std::borrow::Cow;
 use std::sync::Arc;
-use thiserror::Error;
 
 pub mod combine;
 
 mod db;
 mod files;
 pub mod metadata;
-mod walk;
 pub mod watch;
 
 pub static DEFAULT_LINT_REGISTRY: std::sync::LazyLock<LintRegistry> =
@@ -67,46 +66,12 @@ pub struct Project {
     /// The metadata describing the project, including the unresolved options.
     #[return_ref]
     pub metadata: ProjectMetadata,
-
-    /// The resolved project settings.
-    #[return_ref]
-    pub settings: Settings,
-
-    /// The paths that should be included when checking this project.
-    ///
-    /// The default (when this list is empty) is to include all files in the project root
-    /// (that satisfy the configured include and exclude patterns).
-    /// However, it's sometimes desired to only check a subset of the project, e.g. to see
-    /// the diagnostics for a single file or a folder.
-    ///
-    /// This list gets initialized by the paths passed to `knot check <paths>`
-    ///
-    /// ## How is this different from `open_files`?
-    ///
-    /// The `included_paths` is closely related to `open_files`. The only difference is that
-    /// `open_files` is already a resolved set of files whereas `included_paths` is only a list of paths
-    /// that are resolved to files by indexing them. The other difference is that
-    /// new files added to any directory in `included_paths` will be indexed and added to the project
-    /// whereas `open_files` needs to be updated manually (e.g. by the IDE).
-    ///
-    /// In short, `open_files` is cheaper in contexts where the set of files is known, like
-    /// in an IDE when the user only wants to check the open tabs. This could be modeled
-    /// with `included_paths` too but it would require an explicit walk dir step that's simply unnecessary.
-    #[default]
-    #[return_ref]
-    included_paths_list: Vec<SystemPathBuf>,
-
-    /// Diagnostics that were generated when resolving the project settings.
-    #[return_ref]
-    settings_diagnostics: Vec<OptionDiagnostic>,
 }
 
 #[salsa::tracked]
 impl Project {
     pub fn from_metadata(db: &dyn Db, metadata: ProjectMetadata) -> Self {
-        let (settings, settings_diagnostics) = metadata.options().to_settings(db);
-
-        Project::builder(metadata, settings, settings_diagnostics)
+        Project::builder(metadata)
             .durability(Durability::MEDIUM)
             .open_fileset_durability(Durability::LOW)
             .file_set_durability(Durability::LOW)
@@ -121,64 +86,41 @@ impl Project {
         self.metadata(db).name()
     }
 
-    /// Returns the resolved linter rules for the project.
-    ///
-    /// This is a salsa query to prevent re-computing queries if other, unrelated
-    /// settings change. For example, we don't want that changing the terminal settings
-    /// invalidates any type checking queries.
-    #[salsa::tracked]
-    pub fn rules(self, db: &dyn Db) -> Arc<RuleSelection> {
-        self.settings(db).to_rules()
-    }
-
-    /// Returns `true` if `path` is both part of the project and included (see `included_paths_list`).
-    ///
-    /// Unlike [Self::files], this method does not respect `.gitignore` files. It only checks
-    /// the project's include and exclude settings as well as the paths that were passed to `knot check <paths>`.
-    /// This means, that this method is an over-approximation of `Self::files` and may return `true` for paths
-    /// that won't be included when checking the project because they're ignored in a `.gitignore` file.
-    pub fn is_path_included(self, db: &dyn Db, path: &SystemPath) -> bool {
-        ProjectFilesFilter::from_project(db, self).is_included(path)
-    }
-
     pub fn reload(self, db: &mut dyn Db, metadata: ProjectMetadata) {
         tracing::debug!("Reloading project");
         assert_eq!(self.root(db), metadata.root());
 
         if &metadata != self.metadata(db) {
-            let (settings, settings_diagnostics) = metadata.options().to_settings(db);
-
-            if self.settings(db) != &settings {
-                self.set_settings(db).to(settings);
-            }
-
-            if self.settings_diagnostics(db) != &settings_diagnostics {
-                self.set_settings_diagnostics(db).to(settings_diagnostics);
-            }
-
             self.set_metadata(db).to(metadata);
         }
 
         self.reload_files(db);
     }
 
+    pub fn rule_selection(self, db: &dyn Db) -> &RuleSelection {
+        let (selection, _) = self.rule_selection_with_diagnostics(db);
+        selection
+    }
+
+    #[salsa::tracked(return_ref)]
+    fn rule_selection_with_diagnostics(
+        self,
+        db: &dyn Db,
+    ) -> (RuleSelection, Vec<OptionDiagnostic>) {
+        self.metadata(db).options().to_rule_selection(db)
+    }
+
     /// Checks all open files in the project and its dependencies.
-    pub(crate) fn check(self, db: &ProjectDatabase) -> Vec<Box<dyn OldDiagnosticTrait>> {
+    pub(crate) fn check(self, db: &ProjectDatabase) -> Vec<Box<dyn Diagnostic>> {
         let project_span = tracing::debug_span!("Project::check");
         let _span = project_span.enter();
 
         tracing::debug!("Checking project '{name}'", name = self.name(db));
 
-        let mut diagnostics: Vec<Box<dyn OldDiagnosticTrait>> = Vec::new();
-        diagnostics.extend(self.settings_diagnostics(db).iter().map(|diagnostic| {
-            let diagnostic: Box<dyn OldDiagnosticTrait> = Box::new(diagnostic.clone());
-            diagnostic
-        }));
-
-        let files = ProjectFiles::new(db, self);
-
-        diagnostics.extend(files.diagnostics().iter().cloned().map(|diagnostic| {
-            let diagnostic: Box<dyn OldDiagnosticTrait> = Box::new(diagnostic);
+        let mut diagnostics: Vec<Box<dyn Diagnostic>> = Vec::new();
+        let (_, options_diagnostics) = self.rule_selection_with_diagnostics(db);
+        diagnostics.extend(options_diagnostics.iter().map(|diagnostic| {
+            let diagnostic: Box<dyn Diagnostic> = Box::new(diagnostic.clone());
             diagnostic
         }));
 
@@ -189,6 +131,7 @@ impl Project {
         let project_span = project_span.clone();
 
         rayon::scope(move |scope| {
+            let files = ProjectFiles::new(&db, self);
             for file in &files {
                 let result = inner_result.clone();
                 let db = db.clone();
@@ -207,12 +150,13 @@ impl Project {
         Arc::into_inner(result).unwrap().into_inner().unwrap()
     }
 
-    pub(crate) fn check_file(self, db: &dyn Db, file: File) -> Vec<Box<dyn OldDiagnosticTrait>> {
-        let mut file_diagnostics: Vec<_> = self
-            .settings_diagnostics(db)
+    pub(crate) fn check_file(self, db: &dyn Db, file: File) -> Vec<Box<dyn Diagnostic>> {
+        let (_, options_diagnostics) = self.rule_selection_with_diagnostics(db);
+
+        let mut file_diagnostics: Vec<_> = options_diagnostics
             .iter()
             .map(|diagnostic| {
-                let diagnostic: Box<dyn OldDiagnosticTrait> = Box::new(diagnostic.clone());
+                let diagnostic: Box<dyn Diagnostic> = Box::new(diagnostic.clone());
                 diagnostic
             })
             .collect();
@@ -248,30 +192,6 @@ impl Project {
         removed
     }
 
-    pub fn set_included_paths(self, db: &mut dyn Db, paths: Vec<SystemPathBuf>) {
-        tracing::debug!("Setting included paths: {paths}", paths = paths.len());
-
-        self.set_included_paths_list(db).to(paths);
-        self.reload_files(db);
-    }
-
-    /// Returns the paths that should be checked.
-    ///
-    /// The default is to check the entire project in which case this method returns
-    /// the project root. However, users can specify to only check specific sub-folders or
-    /// even files of a project by using `knot check <paths>`. In that case, this method
-    /// returns the provided absolute paths.
-    ///
-    /// Note: The CLI doesn't prohibit users from specifying paths outside the project root.
-    /// This can be useful to check arbitrary files, but it isn't something we recommend.
-    /// We should try to support this use case but it's okay if there are some limitations around it.
-    fn included_paths_or_root(self, db: &dyn Db) -> &[SystemPathBuf] {
-        match &**self.included_paths_list(db) {
-            [] => std::slice::from_ref(&self.metadata(db).root),
-            paths => paths,
-        }
-    }
-
     /// Returns the open files in the project or `None` if the entire project should be checked.
     pub fn open_files(self, db: &dyn Db) -> Option<&FxHashSet<File>> {
         self.open_fileset(db).as_deref()
@@ -354,17 +274,6 @@ impl Project {
         index.insert(file);
     }
 
-    /// Replaces the diagnostics from indexing the project files with `diagnostics`.
-    ///
-    /// This is a no-op if the project files haven't been indexed yet.
-    pub fn replace_index_diagnostics(self, db: &mut dyn Db, diagnostics: Vec<IOErrorDiagnostic>) {
-        let Some(mut index) = IndexedFiles::indexed_mut(db, self) else {
-            return;
-        };
-
-        index.set_diagnostics(diagnostics);
-    }
-
     /// Returns the files belonging to this project.
     pub fn files(self, db: &dyn Db) -> Indexed<'_> {
         let files = self.file_set(db);
@@ -372,14 +281,12 @@ impl Project {
         let indexed = match files.get() {
             Index::Lazy(vacant) => {
                 let _entered =
-                    tracing::debug_span!("Project::index_files", project = %self.name(db))
+                    tracing::debug_span!("Project::index_files", package = %self.name(db))
                         .entered();
 
-                let walker = ProjectFilesWalker::new(db);
-                let (files, diagnostics) = walker.collect_set(db);
-
-                tracing::info!("Indexed {} file(s)", files.len());
-                vacant.set(files, diagnostics)
+                let files = discover_project_files(db, self);
+                tracing::info!("Found {} files in project `{}`", files.len(), self.name(db));
+                vacant.set(files)
             }
             Index::Indexed(indexed) => indexed,
         };
@@ -397,43 +304,83 @@ impl Project {
     }
 }
 
-fn check_file_impl(db: &dyn Db, file: File) -> Vec<Box<dyn OldDiagnosticTrait>> {
-    let mut diagnostics: Vec<Box<dyn OldDiagnosticTrait>> = Vec::new();
+fn check_file_impl(db: &dyn Db, file: File) -> Vec<Box<dyn Diagnostic>> {
+    let mut diagnostics: Vec<Box<dyn Diagnostic>> = Vec::new();
 
     // Abort checking if there are IO errors.
     let source = source_text(db.upcast(), file);
 
     if let Some(read_error) = source.read_error() {
         diagnostics.push(Box::new(IOErrorDiagnostic {
-            file: Some(file),
-            error: read_error.clone().into(),
+            file,
+            error: read_error.clone(),
         }));
         return diagnostics;
     }
 
     let parsed = parsed_module(db.upcast(), file);
     diagnostics.extend(parsed.errors().iter().map(|error| {
-        let diagnostic: Box<dyn OldDiagnosticTrait> =
-            Box::new(OldParseDiagnostic::new(file, error.clone()));
+        let diagnostic: Box<dyn Diagnostic> = Box::new(ParseDiagnostic::new(file, error.clone()));
         diagnostic
     }));
 
     diagnostics.extend(check_types(db.upcast(), file).iter().map(|diagnostic| {
-        let boxed: Box<dyn OldDiagnosticTrait> = Box::new(diagnostic.clone());
+        let boxed: Box<dyn Diagnostic> = Box::new(diagnostic.clone());
         boxed
     }));
 
-    diagnostics.sort_unstable_by_key(|diagnostic| {
-        diagnostic
-            .span()
-            .and_then(|span| span.range())
-            .unwrap_or_default()
-            .start()
-    });
+    diagnostics.sort_unstable_by_key(|diagnostic| diagnostic.range().unwrap_or_default().start());
 
     diagnostics
 }
 
+fn discover_project_files(db: &dyn Db, project: Project) -> FxHashSet<File> {
+    let paths = std::sync::Mutex::new(Vec::new());
+
+    db.system().walk_directory(project.root(db)).run(|| {
+        Box::new(|entry| {
+            match entry {
+                Ok(entry) => {
+                    // Skip over any non python files to avoid creating too many entries in `Files`.
+                    match entry.file_type() {
+                        FileType::File => {
+                            if entry
+                                .path()
+                                .extension()
+                                .and_then(PySourceType::try_from_extension)
+                                .is_some()
+                            {
+                                let mut paths = paths.lock().unwrap();
+                                paths.push(entry.into_path());
+                            }
+                        }
+                        FileType::Directory | FileType::Symlink => {}
+                    }
+                }
+                Err(error) => {
+                    // TODO Handle error
+                    tracing::error!("Failed to walk path: {error}");
+                }
+            }
+
+            WalkState::Continue
+        })
+    });
+
+    let paths = paths.into_inner().unwrap();
+    let mut files = FxHashSet::with_capacity_and_hasher(paths.len(), FxBuildHasher);
+
+    for path in paths {
+        // If this returns `None`, then the file was deleted between the `walk_directory` call and now.
+        // We can ignore this.
+        if let Ok(file) = system_path_to_file(db.upcast(), &path) {
+            files.insert(file);
+        }
+    }
+
+    files
+}
+
 #[derive(Debug)]
 enum ProjectFiles<'a> {
     OpenFiles(&'a FxHashSet<File>),
@@ -448,13 +395,6 @@ impl<'a> ProjectFiles<'a> {
             ProjectFiles::Indexed(project.files(db))
         }
     }
-
-    fn diagnostics(&self) -> &[IOErrorDiagnostic] {
-        match self {
-            ProjectFiles::OpenFiles(_) => &[],
-            ProjectFiles::Indexed(indexed) => indexed.diagnostics(),
-        }
-    }
 }
 
 impl<'a> IntoIterator for &'a ProjectFiles<'a> {
@@ -487,13 +427,13 @@ impl Iterator for ProjectFilesIter<'_> {
     }
 }
 
-#[derive(Debug, Clone)]
+#[derive(Debug)]
 pub struct IOErrorDiagnostic {
-    file: Option<File>,
-    error: IOErrorKind,
+    file: File,
+    error: SourceTextError,
 }
 
-impl OldDiagnosticTrait for IOErrorDiagnostic {
+impl Diagnostic for IOErrorDiagnostic {
     fn id(&self) -> DiagnosticId {
         DiagnosticId::Io
     }
@@ -502,8 +442,12 @@ impl OldDiagnosticTrait for IOErrorDiagnostic {
         self.error.to_string().into()
     }
 
-    fn span(&self) -> Option<Span> {
-        self.file.map(Span::from)
+    fn file(&self) -> Option<File> {
+        Some(self.file)
+    }
+
+    fn range(&self) -> Option<TextRange> {
+        None
     }
 
     fn severity(&self) -> Severity {
@@ -511,24 +455,15 @@ impl OldDiagnosticTrait for IOErrorDiagnostic {
     }
 }
 
-#[derive(Error, Debug, Clone)]
-enum IOErrorKind {
-    #[error(transparent)]
-    Walk(#[from] walk::WalkError),
-
-    #[error(transparent)]
-    SourceText(#[from] SourceTextError),
-}
-
 #[cfg(test)]
 mod tests {
     use crate::db::tests::TestDb;
     use crate::{check_file_impl, ProjectMetadata};
     use red_knot_python_semantic::types::check_types;
-    use ruff_db::diagnostic::OldDiagnosticTrait;
+    use ruff_db::diagnostic::Diagnostic;
     use ruff_db::files::system_path_to_file;
     use ruff_db::source::source_text;
-    use ruff_db::system::{DbWithTestSystem, DbWithWritableSystem as _, SystemPath, SystemPathBuf};
+    use ruff_db::system::{DbWithTestSystem, SystemPath, SystemPathBuf};
     use ruff_db::testing::assert_function_query_was_not_run;
     use ruff_python_ast::name::Name;
 

crates/red_knot_project/src/metadata.rs

@@ -1,4 +1,3 @@
-use configuration_file::{ConfigurationFile, ConfigurationFileError};
 use red_knot_python_semantic::ProgramSettings;
 use ruff_db::system::{System, SystemPath, SystemPathBuf};
 use ruff_python_ast::name::Name;
@@ -6,15 +5,13 @@ use std::sync::Arc;
 use thiserror::Error;
 
 use crate::combine::Combine;
-use crate::metadata::pyproject::{Project, PyProject, PyProjectError, ResolveRequiresPythonError};
+use crate::metadata::pyproject::{Project, PyProject, PyProjectError};
 use crate::metadata::value::ValueSource;
 use options::KnotTomlError;
 use options::Options;
 
-mod configuration_file;
 pub mod options;
 pub mod pyproject;
-pub mod settings;
 pub mod value;
 
 #[derive(Debug, PartialEq, Eq)]
@@ -26,15 +23,6 @@ pub struct ProjectMetadata {
 
     /// The raw options
     pub(super) options: Options,
-
-    /// Paths of configurations other than the project's configuration that were combined into [`Self::options`].
-    ///
-    /// This field stores the paths of the configuration files, mainly for
-    /// knowing which files to watch for changes.
-    ///
-    /// The path ordering doesn't imply precedence.
-    #[cfg_attr(test, serde(skip_serializing_if = "Vec::is_empty"))]
-    pub(super) extra_configuration_paths: Vec<SystemPathBuf>,
 }
 
 impl ProjectMetadata {
@@ -43,16 +31,12 @@ impl ProjectMetadata {
         Self {
             name,
             root,
-            extra_configuration_paths: Vec::default(),
             options: Options::default(),
         }
     }
 
     /// Loads a project from a `pyproject.toml` file.
-    pub(crate) fn from_pyproject(
-        pyproject: PyProject,
-        root: SystemPathBuf,
-    ) -> Result<Self, ResolveRequiresPythonError> {
+    pub(crate) fn from_pyproject(pyproject: PyProject, root: SystemPathBuf) -> Self {
         Self::from_options(
             pyproject
                 .tool
@@ -65,37 +49,21 @@ impl ProjectMetadata {
 
     /// Loads a project from a set of options with an optional pyproject-project table.
     pub(crate) fn from_options(
-        mut options: Options,
+        options: Options,
         root: SystemPathBuf,
         project: Option<&Project>,
-    ) -> Result<Self, ResolveRequiresPythonError> {
+    ) -> Self {
         let name = project
-            .and_then(|project| project.name.as_deref())
-            .map(|name| Name::new(&**name))
+            .and_then(|project| project.name.as_ref())
+            .map(|name| Name::new(&***name))
             .unwrap_or_else(|| Name::new(root.file_name().unwrap_or("root")));
 
-        // If the `options` don't specify a python version but the `project.requires-python` field is set,
-        // use that as a lower bound instead.
-        if let Some(project) = project {
-            if options
-                .environment
-                .as_ref()
-                .is_none_or(|env| env.python_version.is_none())
-            {
-                if let Some(requires_python) = project.resolve_requires_python_lower_bound()? {
-                    let mut environment = options.environment.unwrap_or_default();
-                    environment.python_version = Some(requires_python);
-                    options.environment = Some(environment);
-                }
-            }
-        }
-
-        Ok(Self {
+        // TODO(https://github.com/astral-sh/ruff/issues/15491): Respect requires-python
+        Self {
             name,
             root,
             options,
-            extra_configuration_paths: Vec::new(),
-        })
+        }
     }
 
     /// Discovers the closest project at `path` and returns its metadata.
@@ -163,34 +131,19 @@ impl ProjectMetadata {
                 }
 
                 tracing::debug!("Found project at '{}'", project_root);
-
-                let metadata = ProjectMetadata::from_options(
+                return Ok(ProjectMetadata::from_options(
                     options,
                     project_root.to_path_buf(),
                     pyproject
                         .as_ref()
                         .and_then(|pyproject| pyproject.project.as_ref()),
-                )
-                .map_err(|err| {
-                    ProjectDiscoveryError::InvalidRequiresPythonConstraint {
-                        source: err,
-                        path: pyproject_path,
-                    }
-                })?;
-
-                return Ok(metadata);
+                ));
             }
 
             if let Some(pyproject) = pyproject {
                 let has_knot_section = pyproject.knot().is_some();
                 let metadata =
-                    ProjectMetadata::from_pyproject(pyproject, project_root.to_path_buf())
-                        .map_err(
-                            |err| ProjectDiscoveryError::InvalidRequiresPythonConstraint {
-                                source: err,
-                                path: pyproject_path,
-                            },
-                        )?;
+                    ProjectMetadata::from_pyproject(pyproject, project_root.to_path_buf());
 
                 if has_knot_section {
                     tracing::debug!("Found project at '{}'", project_root);
@@ -238,10 +191,6 @@ impl ProjectMetadata {
         &self.options
     }
 
-    pub fn extra_configuration_paths(&self) -> &[SystemPathBuf] {
-        &self.extra_configuration_paths
-    }
-
     pub fn to_program_settings(&self, system: &dyn System) -> ProgramSettings {
         self.options.to_program_settings(self.root(), system)
     }
@@ -251,31 +200,9 @@ impl ProjectMetadata {
         self.options = options.combine(std::mem::take(&mut self.options));
     }
 
-    /// Applies the options from the configuration files to the project's options.
-    ///
-    /// This includes:
-    ///
-    /// * The user-level configuration
-    pub fn apply_configuration_files(
-        &mut self,
-        system: &dyn System,
-    ) -> Result<(), ConfigurationFileError> {
-        if let Some(user) = ConfigurationFile::user(system)? {
-            tracing::debug!(
-                "Applying user-level configuration loaded from `{path}`.",
-                path = user.path()
-            );
-            self.apply_configuration_file(user);
-        }
-
-        Ok(())
-    }
-
-    /// Applies a lower-precedence configuration files to the project's options.
-    fn apply_configuration_file(&mut self, options: ConfigurationFile) {
-        self.extra_configuration_paths
-            .push(options.path().to_owned());
-        self.options.combine_with(options.into_options());
+    /// Combine the project options with the user options where project options take precedence.
+    pub fn apply_user_options(&mut self, options: Options) {
+        self.options.combine_with(options);
     }
 }
 
@@ -295,22 +222,16 @@ pub enum ProjectDiscoveryError {
         source: Box<KnotTomlError>,
         path: SystemPathBuf,
     },
-
-    #[error("Invalid `requires-python` version specifier (`{path}`): {source}")]
-    InvalidRequiresPythonConstraint {
-        source: ResolveRequiresPythonError,
-        path: SystemPathBuf,
-    },
 }
 
 #[cfg(test)]
 mod tests {
     //! Integration tests for project discovery
 
+    use crate::snapshot_project;
     use anyhow::{anyhow, Context};
     use insta::assert_ron_snapshot;
     use ruff_db::system::{SystemPathBuf, TestSystem};
-    use ruff_python_ast::PythonVersion;
 
     use crate::{ProjectDiscoveryError, ProjectMetadata};
 
@@ -321,7 +242,7 @@ mod tests {
 
         system
             .memory_file_system()
-            .write_files_all([(root.join("foo.py"), ""), (root.join("bar.py"), "")])
+            .write_files([(root.join("foo.py"), ""), (root.join("bar.py"), "")])
             .context("Failed to write files")?;
 
         let project =
@@ -329,15 +250,7 @@ mod tests {
 
         assert_eq!(project.root(), &*root);
 
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(&project, @r#"
-                ProjectMetadata(
-                  name: Name("app"),
-                  root: "/app",
-                  options: Options(),
-                )
-            "#);
-        });
+        snapshot_project!(project);
 
         Ok(())
     }
@@ -349,7 +262,7 @@ mod tests {
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
@@ -366,16 +279,7 @@ mod tests {
             ProjectMetadata::discover(&root, &system).context("Failed to discover project")?;
 
         assert_eq!(project.root(), &*root);
-
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(&project, @r#"
-                ProjectMetadata(
-                  name: Name("backend"),
-                  root: "/app",
-                  options: Options(),
-                )
-            "#);
-        });
+        snapshot_project!(project);
 
         // Discovering the same package from a subdirectory should give the same result
         let from_src = ProjectMetadata::discover(&root.join("db"), &system)
@@ -393,7 +297,7 @@ mod tests {
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
@@ -432,7 +336,7 @@ expected `.`, `]`
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
@@ -458,19 +362,7 @@ expected `.`, `]`
 
         let sub_project = ProjectMetadata::discover(&root.join("packages/a"), &system)?;
 
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(sub_project, @r#"
-            ProjectMetadata(
-              name: Name("nested-project"),
-              root: "/app/packages/a",
-              options: Options(
-                src: Some(SrcOptions(
-                  root: Some("src"),
-                )),
-              ),
-            )
-            "#);
-        });
+        snapshot_project!(sub_project);
 
         Ok(())
     }
@@ -482,7 +374,7 @@ expected `.`, `]`
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
@@ -508,19 +400,7 @@ expected `.`, `]`
 
         let root = ProjectMetadata::discover(&root, &system)?;
 
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(root, @r#"
-                              ProjectMetadata(
-                                name: Name("project-root"),
-                                root: "/app",
-                                options: Options(
-                                  src: Some(SrcOptions(
-                                    root: Some("src"),
-                                  )),
-                                ),
-                              )
-                              "#);
-        });
+        snapshot_project!(root);
 
         Ok(())
     }
@@ -532,7 +412,7 @@ expected `.`, `]`
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
@@ -552,15 +432,7 @@ expected `.`, `]`
 
         let sub_project = ProjectMetadata::discover(&root.join("packages/a"), &system)?;
 
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(sub_project, @r#"
-            ProjectMetadata(
-              name: Name("nested-project"),
-              root: "/app/packages/a",
-              options: Options(),
-            )
-            "#);
-        });
+        snapshot_project!(sub_project);
 
         Ok(())
     }
@@ -572,7 +444,7 @@ expected `.`, `]`
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
@@ -595,19 +467,7 @@ expected `.`, `]`
 
         let root = ProjectMetadata::discover(&root.join("packages/a"), &system)?;
 
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(root, @r#"
-            ProjectMetadata(
-              name: Name("project-root"),
-              root: "/app",
-              options: Options(
-                environment: Some(EnvironmentOptions(
-                  r#python-version: Some("3.10"),
-                )),
-              ),
-            )
-            "#);
-        });
+        snapshot_project!(root);
 
         Ok(())
     }
@@ -623,308 +483,31 @@ expected `.`, `]`
 
         system
             .memory_file_system()
-            .write_files_all([
+            .write_files([
                 (
                     root.join("pyproject.toml"),
                     r#"
-                    [project]
-                    name = "super-app"
-                    requires-python = ">=3.12"
+                        [project]
+                        name = "super-app"
+                        requires-python = ">=3.12"
 
-                    [tool.knot.src]
-                    root = "this_option_is_ignored"
-                    "#,
+                        [tool.knot.src]
+                        root = "this_option_is_ignored"
+                        "#,
                 ),
                 (
                     root.join("knot.toml"),
                     r#"
-                    [src]
-                    root = "src"
-                    "#,
+                        [src]
+                        root = "src"
+                        "#,
                 ),
             ])
             .context("Failed to write files")?;
 
         let root = ProjectMetadata::discover(&root, &system)?;
 
-        with_escaped_paths(|| {
-            assert_ron_snapshot!(root, @r#"
-            ProjectMetadata(
-              name: Name("super-app"),
-              root: "/app",
-              options: Options(
-                environment: Some(EnvironmentOptions(
-                  r#python-version: Some("3.12"),
-                )),
-                src: Some(SrcOptions(
-                  root: Some("src"),
-                )),
-              ),
-            )
-            "#);
-        });
-
-        Ok(())
-    }
-    #[test]
-    fn requires_python_major_minor() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ">=3.12"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let root = ProjectMetadata::discover(&root, &system)?;
-
-        assert_eq!(
-            root.options
-                .environment
-                .unwrap_or_default()
-                .python_version
-                .as_deref(),
-            Some(&PythonVersion::PY312)
-        );
-
-        Ok(())
-    }
-
-    #[test]
-    fn requires_python_major_only() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ">=3"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let root = ProjectMetadata::discover(&root, &system)?;
-
-        assert_eq!(
-            root.options
-                .environment
-                .unwrap_or_default()
-                .python_version
-                .as_deref(),
-            Some(&PythonVersion::from((3, 0)))
-        );
-
-        Ok(())
-    }
-
-    /// A `requires-python` constraint with major, minor and patch can be simplified
-    /// to major and minor (e.g. 3.12.1 -> 3.12).
-    #[test]
-    fn requires_python_major_minor_patch() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ">=3.12.8"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let root = ProjectMetadata::discover(&root, &system)?;
-
-        assert_eq!(
-            root.options
-                .environment
-                .unwrap_or_default()
-                .python_version
-                .as_deref(),
-            Some(&PythonVersion::PY312)
-        );
-
-        Ok(())
-    }
-
-    #[test]
-    fn requires_python_beta_version() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ">= 3.13.0b0"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let root = ProjectMetadata::discover(&root, &system)?;
-
-        assert_eq!(
-            root.options
-                .environment
-                .unwrap_or_default()
-                .python_version
-                .as_deref(),
-            Some(&PythonVersion::PY313)
-        );
-
-        Ok(())
-    }
-
-    #[test]
-    fn requires_python_greater_than_major_minor() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                # This is somewhat nonsensical because 3.12.1 > 3.12 is true.
-                # That's why simplifying the constraint to >= 3.12 is correct
-                requires-python = ">3.12"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let root = ProjectMetadata::discover(&root, &system)?;
-
-        assert_eq!(
-            root.options
-                .environment
-                .unwrap_or_default()
-                .python_version
-                .as_deref(),
-            Some(&PythonVersion::PY312)
-        );
-
-        Ok(())
-    }
-
-    /// `python-version` takes precedence if both `requires-python` and `python-version` are configured.
-    #[test]
-    fn requires_python_and_python_version() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ">=3.12"
-
-                [tool.knot.environment]
-                python-version = "3.10"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let root = ProjectMetadata::discover(&root, &system)?;
-
-        assert_eq!(
-            root.options
-                .environment
-                .unwrap_or_default()
-                .python_version
-                .as_deref(),
-            Some(&PythonVersion::PY310)
-        );
-
-        Ok(())
-    }
-
-    #[test]
-    fn requires_python_less_than() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = "<3.12"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let Err(error) = ProjectMetadata::discover(&root, &system) else {
-            return Err(anyhow!("Expected project discovery to fail because the `requires-python` doesn't specify a lower bound (it only specifies an upper bound)."));
-        };
-
-        assert_error_eq(&error, "Invalid `requires-python` version specifier (`/app/pyproject.toml`): value `<3.12` does not contain a lower bound. Add a lower bound to indicate the minimum compatible Python version (e.g., `>=3.13`) or specify a version in `environment.python-version`.");
-
-        Ok(())
-    }
-
-    #[test]
-    fn requires_python_no_specifiers() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ""
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let Err(error) = ProjectMetadata::discover(&root, &system) else {
-            return Err(anyhow!("Expected project discovery to fail because the `requires-python` specifiers are empty and don't define a lower bound."));
-        };
-
-        assert_error_eq(&error, "Invalid `requires-python` version specifier (`/app/pyproject.toml`): value `` does not contain a lower bound. Add a lower bound to indicate the minimum compatible Python version (e.g., `>=3.13`) or specify a version in `environment.python-version`.");
-
-        Ok(())
-    }
-
-    #[test]
-    fn requires_python_too_large_major_version() -> anyhow::Result<()> {
-        let system = TestSystem::default();
-        let root = SystemPathBuf::from("/app");
-
-        system
-            .memory_file_system()
-            .write_file_all(
-                root.join("pyproject.toml"),
-                r#"
-                [project]
-                requires-python = ">=999.0"
-                "#,
-            )
-            .context("Failed to write file")?;
-
-        let Err(error) = ProjectMetadata::discover(&root, &system) else {
-            return Err(anyhow!("Expected project discovery to fail because of the requires-python major version that is larger than 255."));
-        };
-
-        assert_error_eq(&error, "Invalid `requires-python` version specifier (`/app/pyproject.toml`): The major version `999` is larger than the maximum supported value 255");
+        snapshot_project!(root);
 
         Ok(())
     }
@@ -934,12 +517,15 @@ expected `.`, `]`
         assert_eq!(error.to_string().replace('\\', "/"), message);
     }
 
-    fn with_escaped_paths<R>(f: impl FnOnce() -> R) -> R {
-        let mut settings = insta::Settings::clone_current();
-        settings.add_dynamic_redaction(".root", |content, _path| {
-            content.as_str().unwrap().replace('\\', "/")
+    /// Snapshots a project but with all paths using unix separators.
+    #[macro_export]
+    macro_rules! snapshot_project {
+    ($project:expr) => {{
+        assert_ron_snapshot!($project,{
+            ".root" => insta::dynamic_redaction(|content, _content_path| {
+                content.as_str().unwrap().replace("\\", "/")
+            }),
         });
-
-        settings.bind(f)
-    }
+    }};
+}
 }

crates/red_knot_project/src/metadata/configuration_file.rs

@@ -1,69 +0,0 @@
-use std::sync::Arc;
-
-use ruff_db::system::{System, SystemPath, SystemPathBuf};
-use thiserror::Error;
-
-use crate::metadata::value::ValueSource;
-
-use super::options::{KnotTomlError, Options};
-
-/// A `knot.toml` configuration file with the options it contains.
-pub(crate) struct ConfigurationFile {
-    path: SystemPathBuf,
-    options: Options,
-}
-
-impl ConfigurationFile {
-    /// Loads the user-level configuration file if it exists.
-    ///
-    /// Returns `None` if the file does not exist or if the concept of user-level configurations
-    /// doesn't exist on `system`.
-    pub(crate) fn user(system: &dyn System) -> Result<Option<Self>, ConfigurationFileError> {
-        let Some(configuration_directory) = system.user_config_directory() else {
-            return Ok(None);
-        };
-
-        let knot_toml_path = configuration_directory.join("knot").join("knot.toml");
-
-        tracing::debug!(
-            "Searching for a user-level configuration at `{path}`",
-            path = &knot_toml_path
-        );
-
-        let Ok(knot_toml_str) = system.read_to_string(&knot_toml_path) else {
-            return Ok(None);
-        };
-
-        match Options::from_toml_str(
-            &knot_toml_str,
-            ValueSource::File(Arc::new(knot_toml_path.clone())),
-        ) {
-            Ok(options) => Ok(Some(Self {
-                path: knot_toml_path,
-                options,
-            })),
-            Err(error) => Err(ConfigurationFileError::InvalidKnotToml {
-                source: Box::new(error),
-                path: knot_toml_path,
-            }),
-        }
-    }
-
-    /// Returns the path to the configuration file.
-    pub(crate) fn path(&self) -> &SystemPath {
-        &self.path
-    }
-
-    pub(crate) fn into_options(self) -> Options {
-        self.options
-    }
-}
-
-#[derive(Debug, Error)]
-pub enum ConfigurationFileError {
-    #[error("{path} is not a valid `knot.toml`: {source}")]
-    InvalidKnotToml {
-        source: Box<KnotTomlError>,
-        path: SystemPathBuf,
-    },
-}

crates/red_knot_project/src/metadata/options.rs

@@ -1,38 +1,32 @@
 use crate::metadata::value::{RangedValue, RelativePathBuf, ValueSource, ValueSourceGuard};
 use crate::Db;
 use red_knot_python_semantic::lint::{GetLintError, Level, LintSource, RuleSelection};
-use red_knot_python_semantic::{ProgramSettings, PythonPath, PythonPlatform, SearchPathSettings};
-use ruff_db::diagnostic::{DiagnosticId, OldDiagnosticTrait, Severity, Span};
-use ruff_db::files::system_path_to_file;
+use red_knot_python_semantic::{
+    ProgramSettings, PythonPlatform, PythonVersion, SearchPathSettings, SitePackages,
+};
+use ruff_db::diagnostic::{Diagnostic, DiagnosticId, Severity};
+use ruff_db::files::{system_path_to_file, File};
 use ruff_db::system::{System, SystemPath};
 use ruff_macros::Combine;
-use ruff_python_ast::PythonVersion;
+use ruff_text_size::TextRange;
 use rustc_hash::FxHashMap;
 use serde::{Deserialize, Serialize};
 use std::borrow::Cow;
 use std::fmt::Debug;
 use thiserror::Error;
 
-use super::settings::{Settings, TerminalSettings};
-
 /// The options for the project.
 #[derive(Debug, Default, Clone, PartialEq, Eq, Combine, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case", deny_unknown_fields)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 pub struct Options {
-    /// Configures the type checking environment.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub environment: Option<EnvironmentOptions>,
 
     #[serde(skip_serializing_if = "Option::is_none")]
     pub src: Option<SrcOptions>,
 
-    /// Configures the enabled lints and their severity.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub rules: Option<Rules>,
-
-    #[serde(skip_serializing_if = "Option::is_none")]
-    pub terminal: Option<TerminalOptions>,
 }
 
 impl Options {
@@ -90,7 +84,7 @@ impl Options {
             .map(|env| {
                 (
                     env.extra_paths.clone(),
-                    env.python.clone(),
+                    env.venv_path.clone(),
                     env.typeshed.clone(),
                 )
             })
@@ -104,31 +98,16 @@ impl Options {
                 .collect(),
             src_roots,
             custom_typeshed: typeshed.map(|path| path.absolute(project_root, system)),
-            python_path: python
-                .map(|python_path| {
-                    PythonPath::SysPrefix(python_path.absolute(project_root, system))
+            site_packages: python
+                .map(|venv_path| SitePackages::Derived {
+                    venv_path: venv_path.absolute(project_root, system),
                 })
-                .unwrap_or(PythonPath::KnownSitePackages(vec![])),
+                .unwrap_or(SitePackages::Known(vec![])),
         }
     }
 
     #[must_use]
-    pub(crate) fn to_settings(&self, db: &dyn Db) -> (Settings, Vec<OptionDiagnostic>) {
-        let (rules, diagnostics) = self.to_rule_selection(db);
-
-        let mut settings = Settings::new(rules);
-
-        if let Some(terminal) = self.terminal.as_ref() {
-            settings.set_terminal(TerminalSettings {
-                error_on_warning: terminal.error_on_warning.unwrap_or_default(),
-            });
-        }
-
-        (settings, diagnostics)
-    }
-
-    #[must_use]
-    fn to_rule_selection(&self, db: &dyn Db) -> (RuleSelection, Vec<OptionDiagnostic>) {
+    pub(crate) fn to_rule_selection(&self, db: &dyn Db) -> (RuleSelection, Vec<OptionDiagnostic>) {
         let registry = db.lint_registry();
         let mut diagnostics = Vec::new();
 
@@ -187,14 +166,7 @@ impl Options {
                         ),
                     };
 
-                    let span = file.map(Span::from).map(|span| {
-                        if let Some(range) = rule_name.range() {
-                            span.with_range(range)
-                        } else {
-                            span
-                        }
-                    });
-                    diagnostics.push(diagnostic.with_span(span));
+                    diagnostics.push(diagnostic.with_file(file).with_range(rule_name.range()));
                 }
             }
         }
@@ -205,22 +177,10 @@ impl Options {
 
 #[derive(Debug, Default, Clone, Eq, PartialEq, Combine, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case", deny_unknown_fields)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 pub struct EnvironmentOptions {
-    /// Specifies the version of Python that will be used to execute the source code.
-    /// The version should be specified as a string in the format `M.m` where `M` is the major version
-    /// and `m` is the minor (e.g. "3.0" or "3.6").
-    /// If a version is provided, knot will generate errors if the source code makes use of language features
-    /// that are not supported in that version.
-    /// It will also tailor its use of type stub files, which conditionalizes type definitions based on the version.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub python_version: Option<RangedValue<PythonVersion>>,
 
-    /// Specifies the target platform that will be used to execute the source code.
-    /// If specified, Red Knot will tailor its use of type stub files,
-    /// which conditionalize type definitions based on the platform.
-    ///
-    /// If no platform is specified, knot will use `all` or the current platform in the LSP use case.
     #[serde(skip_serializing_if = "Option::is_none")]
     pub python_platform: Option<RangedValue<PythonPlatform>>,
 
@@ -236,19 +196,14 @@ pub struct EnvironmentOptions {
     #[serde(skip_serializing_if = "Option::is_none")]
     pub typeshed: Option<RelativePathBuf>,
 
-    /// Path to the Python installation from which Red Knot resolves type information and third-party dependencies.
-    ///
-    /// Red Knot will search in the path's `site-packages` directories for type information and
-    /// third-party imports.
-    ///
-    /// This option is commonly used to specify the path to a virtual environment.
+    // TODO: Rename to python, see https://github.com/astral-sh/ruff/issues/15530
+    /// The path to the user's `site-packages` directory, where third-party packages from ``PyPI`` are installed.
     #[serde(skip_serializing_if = "Option::is_none")]
-    pub python: Option<RelativePathBuf>,
+    pub venv_path: Option<RelativePathBuf>,
 }
 
 #[derive(Debug, Default, Clone, Eq, PartialEq, Combine, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case", deny_unknown_fields)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 pub struct SrcOptions {
     /// The root of the project, used for finding first-party modules.
     #[serde(skip_serializing_if = "Option::is_none")]
@@ -257,9 +212,7 @@ pub struct SrcOptions {
 
 #[derive(Debug, Default, Clone, Eq, PartialEq, Combine, Serialize, Deserialize)]
 #[serde(rename_all = "kebab-case", transparent)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 pub struct Rules {
-    #[cfg_attr(feature = "schemars", schemars(with = "schema::Rules"))]
     inner: FxHashMap<RangedValue<String>, RangedValue<Level>>,
 }
 
@@ -273,79 +226,6 @@ impl FromIterator<(RangedValue<String>, RangedValue<Level>)> for Rules {
     }
 }
 
-#[derive(Debug, Default, Clone, Eq, PartialEq, Combine, Serialize, Deserialize)]
-#[serde(rename_all = "kebab-case", deny_unknown_fields)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
-pub struct TerminalOptions {
-    /// Use exit code 1 if there are any warning-level diagnostics.
-    ///
-    /// Defaults to `false`.
-    pub error_on_warning: Option<bool>,
-}
-
-#[cfg(feature = "schemars")]
-mod schema {
-    use crate::DEFAULT_LINT_REGISTRY;
-    use red_knot_python_semantic::lint::Level;
-    use schemars::gen::SchemaGenerator;
-    use schemars::schema::{
-        InstanceType, Metadata, ObjectValidation, Schema, SchemaObject, SubschemaValidation,
-    };
-    use schemars::JsonSchema;
-
-    pub(super) struct Rules;
-
-    impl JsonSchema for Rules {
-        fn schema_name() -> String {
-            "Rules".to_string()
-        }
-
-        fn json_schema(gen: &mut SchemaGenerator) -> Schema {
-            let registry = &*DEFAULT_LINT_REGISTRY;
-
-            let level_schema = gen.subschema_for::<Level>();
-
-            let properties: schemars::Map<String, Schema> = registry
-                .lints()
-                .iter()
-                .map(|lint| {
-                    (
-                        lint.name().to_string(),
-                        Schema::Object(SchemaObject {
-                            metadata: Some(Box::new(Metadata {
-                                title: Some(lint.summary().to_string()),
-                                description: Some(lint.documentation()),
-                                deprecated: lint.status.is_deprecated(),
-                                default: Some(lint.default_level.to_string().into()),
-                                ..Metadata::default()
-                            })),
-                            subschemas: Some(Box::new(SubschemaValidation {
-                                one_of: Some(vec![level_schema.clone()]),
-                                ..Default::default()
-                            })),
-                            ..Default::default()
-                        }),
-                    )
-                })
-                .collect();
-
-            Schema::Object(SchemaObject {
-                instance_type: Some(InstanceType::Object.into()),
-                object: Some(Box::new(ObjectValidation {
-                    properties,
-                    // Allow unknown rules: Red Knot will warn about them.
-                    // It gives a better experience when using an older Red Knot version because
-                    // the schema will not deny rules that have been removed in newer versions.
-                    additional_properties: Some(Box::new(level_schema)),
-                    ..ObjectValidation::default()
-                })),
-
-                ..Default::default()
-            })
-        }
-    }
-}
-
 #[derive(Error, Debug)]
 pub enum KnotTomlError {
     #[error(transparent)]
@@ -357,7 +237,8 @@ pub struct OptionDiagnostic {
     id: DiagnosticId,
     message: String,
     severity: Severity,
-    span: Option<Span>,
+    file: Option<File>,
+    range: Option<TextRange>,
 }
 
 impl OptionDiagnostic {
@@ -366,17 +247,25 @@ impl OptionDiagnostic {
             id,
             message,
             severity,
-            span: None,
+            file: None,
+            range: None,
         }
     }
 
     #[must_use]
-    fn with_span(self, span: Option<Span>) -> Self {
-        OptionDiagnostic { span, ..self }
+    fn with_file(mut self, file: Option<File>) -> Self {
+        self.file = file;
+        self
+    }
+
+    #[must_use]
+    fn with_range(mut self, range: Option<TextRange>) -> Self {
+        self.range = range;
+        self
     }
 }
 
-impl OldDiagnosticTrait for OptionDiagnostic {
+impl Diagnostic for OptionDiagnostic {
     fn id(&self) -> DiagnosticId {
         self.id
     }
@@ -385,8 +274,12 @@ impl OldDiagnosticTrait for OptionDiagnostic {
         Cow::Borrowed(&self.message)
     }
 
-    fn span(&self) -> Option<Span> {
-        self.span.clone()
+    fn file(&self) -> Option<File> {
+        self.file
+    }
+
+    fn range(&self) -> Option<TextRange> {
+        self.range
     }
 
     fn severity(&self) -> Severity {

crates/red_knot_project/src/metadata/pyproject.rs

@@ -1,12 +1,11 @@
-use crate::metadata::options::Options;
-use crate::metadata::value::{RangedValue, ValueSource, ValueSourceGuard};
-use pep440_rs::{release_specifiers_to_ranges, Version, VersionSpecifiers};
-use ruff_python_ast::PythonVersion;
+use pep440_rs::{Version, VersionSpecifiers};
 use serde::{Deserialize, Deserializer, Serialize};
-use std::collections::Bound;
 use std::ops::Deref;
 use thiserror::Error;
 
+use crate::metadata::options::Options;
+use crate::metadata::value::{RangedValue, ValueSource, ValueSourceGuard};
+
 /// A `pyproject.toml` as specified in PEP 517.
 #[derive(Deserialize, Serialize, Debug, Default, Clone)]
 #[serde(rename_all = "kebab-case")]
@@ -56,73 +55,6 @@ pub struct Project {
     pub requires_python: Option<RangedValue<VersionSpecifiers>>,
 }
 
-impl Project {
-    pub(super) fn resolve_requires_python_lower_bound(
-        &self,
-    ) -> Result<Option<RangedValue<PythonVersion>>, ResolveRequiresPythonError> {
-        let Some(requires_python) = self.requires_python.as_ref() else {
-            return Ok(None);
-        };
-
-        tracing::debug!("Resolving requires-python constraint: `{requires_python}`");
-
-        let ranges = release_specifiers_to_ranges((**requires_python).clone());
-        let Some((lower, _)) = ranges.bounding_range() else {
-            return Ok(None);
-        };
-
-        let version = match lower {
-            // Ex) `>=3.10.1` -> `>=3.10`
-            Bound::Included(version) => version,
-
-            // Ex) `>3.10.1` -> `>=3.10` or `>3.10` -> `>=3.10`
-            // The second example looks obscure at first but it is required because
-            // `3.10.1 > 3.10` is true but we only have two digits here. So including 3.10 is the
-            // right move. Overall, using `>` without a patch release is most likely bogus.
-            Bound::Excluded(version) => version,
-
-            // Ex) `<3.10` or ``
-            Bound::Unbounded => {
-                return Err(ResolveRequiresPythonError::NoLowerBound(
-                    requires_python.to_string(),
-                ))
-            }
-        };
-
-        // Take the major and minor version
-        let mut versions = version.release().iter().take(2);
-
-        let Some(major) = versions.next().copied() else {
-            return Ok(None);
-        };
-
-        let minor = versions.next().copied().unwrap_or_default();
-
-        tracing::debug!("Resolved requires-python constraint to: {major}.{minor}");
-
-        let major =
-            u8::try_from(major).map_err(|_| ResolveRequiresPythonError::TooLargeMajor(major))?;
-        let minor =
-            u8::try_from(minor).map_err(|_| ResolveRequiresPythonError::TooLargeMajor(minor))?;
-
-        Ok(Some(
-            requires_python
-                .clone()
-                .map_value(|_| PythonVersion::from((major, minor))),
-        ))
-    }
-}
-
-#[derive(Debug, Error)]
-pub enum ResolveRequiresPythonError {
-    #[error("The major version `{0}` is larger than the maximum supported value 255")]
-    TooLargeMajor(u64),
-    #[error("The minor version `{0}` is larger than the maximum supported value 255")]
-    TooLargeMinor(u64),
-    #[error("value `{0}` does not contain a lower bound. Add a lower bound to indicate the minimum compatible Python version (e.g., `>=3.13`) or specify a version in `environment.python-version`.")]
-    NoLowerBound(String),
-}
-
 #[derive(Deserialize, Serialize, Debug, Clone, PartialEq, Eq)]
 #[serde(rename_all = "kebab-case")]
 pub struct Tool {

crates/red_knot_project/src/metadata/settings.rs

@@ -1,53 +0,0 @@
-use std::sync::Arc;
-
-use red_knot_python_semantic::lint::RuleSelection;
-
-/// The resolved [`super::Options`] for the project.
-///
-/// Unlike [`super::Options`], the struct has default values filled in and
-/// uses representations that are optimized for reads (instead of preserving the source representation).
-/// It's also not required that this structure precisely resembles the TOML schema, although
-/// it's encouraged to use a similar structure.
-///
-/// It's worth considering to adding a salsa query for specific settings to
-/// limit the blast radius when only some settings change. For example,
-/// changing the terminal settings shouldn't invalidate any core type-checking queries.
-/// This can be achieved by adding a salsa query for the type checking specific settings.
-///
-/// Settings that are part of [`red_knot_python_semantic::ProgramSettings`] are not included here.
-#[derive(Clone, Debug, Eq, PartialEq)]
-pub struct Settings {
-    rules: Arc<RuleSelection>,
-
-    terminal: TerminalSettings,
-}
-
-impl Settings {
-    pub fn new(rules: RuleSelection) -> Self {
-        Self {
-            rules: Arc::new(rules),
-            terminal: TerminalSettings::default(),
-        }
-    }
-
-    pub fn rules(&self) -> &RuleSelection {
-        &self.rules
-    }
-
-    pub fn to_rules(&self) -> Arc<RuleSelection> {
-        self.rules.clone()
-    }
-
-    pub fn terminal(&self) -> &TerminalSettings {
-        &self.terminal
-    }
-
-    pub fn set_terminal(&mut self, terminal: TerminalSettings) {
-        self.terminal = terminal;
-    }
-}
-
-#[derive(Debug, Clone, PartialEq, Eq, Default)]
-pub struct TerminalSettings {
-    pub error_on_warning: bool,
-}

crates/red_knot_project/src/metadata/value.rs

@@ -1,9 +1,8 @@
 use crate::combine::Combine;
 use crate::Db;
 use ruff_db::system::{System, SystemPath, SystemPathBuf};
-use ruff_macros::Combine;
 use ruff_text_size::{TextRange, TextSize};
-use serde::{Deserialize, Deserializer};
+use serde::{Deserialize, Deserializer, Serialize, Serializer};
 use std::cell::RefCell;
 use std::cmp::Ordering;
 use std::fmt;
@@ -71,19 +70,15 @@ impl Drop for ValueSourceGuard {
 ///
 /// This ensures that two resolved configurations are identical even if the position of a value has changed
 /// or if the values were loaded from different sources.
-#[derive(Clone, serde::Serialize)]
-#[serde(transparent)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
+#[derive(Clone)]
 pub struct RangedValue<T> {
     value: T,
-    #[serde(skip)]
     source: ValueSource,
 
     /// The byte range of `value` in `source`.
     ///
     /// Can be `None` because not all sources support a range.
     /// For example, arguments provided on the CLI won't have a range attached.
-    #[serde(skip)]
     range: Option<TextRange>,
 }
 
@@ -118,15 +113,6 @@ impl<T> RangedValue<T> {
         self
     }
 
-    #[must_use]
-    pub fn map_value<R>(self, f: impl FnOnce(T) -> R) -> RangedValue<R> {
-        RangedValue {
-            value: f(self.value),
-            source: self.source,
-            range: self.range,
-        }
-    }
-
     pub fn into_inner(self) -> T {
         self.value
     }
@@ -280,6 +266,18 @@ where
     }
 }
 
+impl<T> Serialize for RangedValue<T>
+where
+    T: Serialize,
+{
+    fn serialize<S>(&self, serializer: S) -> Result<S::Ok, S::Error>
+    where
+        S: Serializer,
+    {
+        self.value.serialize(serializer)
+    }
+}
+
 /// A possibly relative path in a configuration file.
 ///
 /// Relative paths in configuration files or from CLI options
@@ -288,19 +286,9 @@ where
 /// * CLI: The path is relative to the current working directory
 /// * Configuration file: The path is relative to the project's root.
 #[derive(
-    Debug,
-    Clone,
-    serde::Serialize,
-    serde::Deserialize,
-    PartialEq,
-    Eq,
-    PartialOrd,
-    Ord,
-    Hash,
-    Combine,
+    Debug, Clone, serde::Serialize, serde::Deserialize, PartialEq, Eq, PartialOrd, Ord, Hash,
 )]
 #[serde(transparent)]
-#[cfg_attr(feature = "schemars", derive(schemars::JsonSchema))]
 pub struct RelativePathBuf(RangedValue<SystemPathBuf>);
 
 impl RelativePathBuf {
@@ -337,3 +325,13 @@ impl RelativePathBuf {
         SystemPath::absolute(&self.0, relative_to)
     }
 }
+
+impl Combine for RelativePathBuf {
+    fn combine(self, other: Self) -> Self {
+        Self(self.0.combine(other.0))
+    }
+
+    fn combine_with(&mut self, other: Self) {
+        self.0.combine_with(other.0);
+    }
+}

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__nested_projects_in_root_project.snap

@@ -0,0 +1,13 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: root
+---
+ProjectMetadata(
+  name: Name("project-root"),
+  root: "/app",
+  options: Options(
+    src: Some(SrcOptions(
+      root: Some("src"),
+    )),
+  ),
+)

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__nested_projects_in_sub_project.snap

@@ -0,0 +1,13 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: sub_project
+---
+ProjectMetadata(
+  name: Name("nested-project"),
+  root: "/app/packages/a",
+  options: Options(
+    src: Some(SrcOptions(
+      root: Some("src"),
+    )),
+  ),
+)

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__nested_projects_with_outer_knot_section.snap

@@ -0,0 +1,13 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: root
+---
+ProjectMetadata(
+  name: Name("project-root"),
+  root: "/app",
+  options: Options(
+    environment: Some(EnvironmentOptions(
+      r#python-version: Some("3.10"),
+    )),
+  ),
+)

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__nested_projects_without_knot_sections.snap

@@ -0,0 +1,9 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: sub_project
+---
+ProjectMetadata(
+  name: Name("nested-project"),
+  root: "/app/packages/a",
+  options: Options(),
+)

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__project_with_knot_and_pyproject_toml.snap

@@ -0,0 +1,13 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: root
+---
+ProjectMetadata(
+  name: Name("super-app"),
+  root: "/app",
+  options: Options(
+    src: Some(SrcOptions(
+      root: Some("src"),
+    )),
+  ),
+)

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__project_with_pyproject.snap

@@ -0,0 +1,9 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: project
+---
+ProjectMetadata(
+  name: Name("backend"),
+  root: "/app",
+  options: Options(),
+)

crates/red_knot_project/src/snapshots/red_knot_project__metadata__tests__project_without_pyproject.snap

@@ -0,0 +1,9 @@
+---
+source: crates/red_knot_project/src/metadata.rs
+expression: project
+---
+ProjectMetadata(
+  name: Name("app"),
+  root: "/app",
+  options: Options(),
+)

crates/red_knot_project/src/walk.rs

@@ -1,256 +0,0 @@
-use crate::{Db, IOErrorDiagnostic, IOErrorKind, Project};
-use ruff_db::files::{system_path_to_file, File};
-use ruff_db::system::walk_directory::{ErrorKind, WalkDirectoryBuilder, WalkState};
-use ruff_db::system::{FileType, SystemPath, SystemPathBuf};
-use ruff_python_ast::PySourceType;
-use rustc_hash::{FxBuildHasher, FxHashSet};
-use std::path::PathBuf;
-use thiserror::Error;
-
-/// Filter that decides which files are included in the project.
-///
-/// In the future, this will hold a reference to the `include` and `exclude` pattern.
-///
-/// This struct mainly exists because `dyn Db` isn't `Send` or `Sync`, making it impossible
-/// to access fields from within the walker.
-#[derive(Default, Debug)]
-pub(crate) struct ProjectFilesFilter<'a> {
-    /// The same as [`Project::included_paths_or_root`].
-    included_paths: &'a [SystemPathBuf],
-
-    /// The filter skips checking if the path is in `included_paths` if set to `true`.
-    ///
-    /// Skipping this check is useful when the walker only walks over `included_paths`.
-    skip_included_paths: bool,
-}
-
-impl<'a> ProjectFilesFilter<'a> {
-    pub(crate) fn from_project(db: &'a dyn Db, project: Project) -> Self {
-        Self {
-            included_paths: project.included_paths_or_root(db),
-            skip_included_paths: false,
-        }
-    }
-
-    /// Returns `true` if a file is part of the project and included in the paths to check.
-    ///
-    /// A file is included in the checked files if it is a sub path of the project's root
-    /// (when no CLI path arguments are specified) or if it is a sub path of any path provided on the CLI (`knot check <paths>`) AND:
-    ///
-    /// * It matches a positive `include` pattern and isn't excluded by a later negative `include` pattern.
-    /// * It doesn't match a positive `exclude` pattern or is re-included by a later negative `exclude` pattern.
-    ///
-    /// ## Note
-    ///
-    /// This method may return `true` for files that don't end up being included when walking the
-    /// project tree because it doesn't consider `.gitignore` and other ignore files when deciding
-    /// if a file's included.
-    pub(crate) fn is_included(&self, path: &SystemPath) -> bool {
-        #[derive(Copy, Clone, Debug, PartialEq, Eq, PartialOrd, Ord)]
-        enum CheckPathMatch {
-            /// The path is a partial match of the checked path (it's a sub path)
-            Partial,
-
-            /// The path matches a check path exactly.
-            Full,
-        }
-
-        let m = if self.skip_included_paths {
-            Some(CheckPathMatch::Partial)
-        } else {
-            self.included_paths
-                .iter()
-                .filter_map(|included_path| {
-                    if let Ok(relative_path) = path.strip_prefix(included_path) {
-                        // Exact matches are always included
-                        if relative_path.as_str().is_empty() {
-                            Some(CheckPathMatch::Full)
-                        } else {
-                            Some(CheckPathMatch::Partial)
-                        }
-                    } else {
-                        None
-                    }
-                })
-                .max()
-        };
-
-        match m {
-            None => false,
-            Some(CheckPathMatch::Partial) => {
-                // TODO: For partial matches, only include the file if it is included by the project's include/exclude settings.
-                true
-            }
-            Some(CheckPathMatch::Full) => true,
-        }
-    }
-}
-
-pub(crate) struct ProjectFilesWalker<'a> {
-    walker: WalkDirectoryBuilder,
-
-    filter: ProjectFilesFilter<'a>,
-}
-
-impl<'a> ProjectFilesWalker<'a> {
-    pub(crate) fn new(db: &'a dyn Db) -> Self {
-        let project = db.project();
-
-        let mut filter = ProjectFilesFilter::from_project(db, project);
-        // It's unnecessary to filter on included paths because it only iterates over those to start with.
-        filter.skip_included_paths = true;
-
-        Self::from_paths(db, project.included_paths_or_root(db), filter)
-            .expect("included_paths_or_root to never return an empty iterator")
-    }
-
-    /// Creates a walker for indexing the project files incrementally.
-    ///
-    /// The main difference to a full project walk is that `paths` may contain paths
-    /// that aren't part of the included files.
-    pub(crate) fn incremental<P>(db: &'a dyn Db, paths: impl IntoIterator<Item = P>) -> Option<Self>
-    where
-        P: AsRef<SystemPath>,
-    {
-        let project = db.project();
-
-        let filter = ProjectFilesFilter::from_project(db, project);
-
-        Self::from_paths(db, paths, filter)
-    }
-
-    fn from_paths<P>(
-        db: &'a dyn Db,
-        paths: impl IntoIterator<Item = P>,
-        filter: ProjectFilesFilter<'a>,
-    ) -> Option<Self>
-    where
-        P: AsRef<SystemPath>,
-    {
-        let mut paths = paths.into_iter();
-
-        let mut walker = db.system().walk_directory(paths.next()?.as_ref());
-
-        for path in paths {
-            walker = walker.add(path);
-        }
-
-        Some(Self { walker, filter })
-    }
-
-    /// Walks the project paths and collects the paths of all files that
-    /// are included in the project.
-    pub(crate) fn walk_paths(self) -> (Vec<SystemPathBuf>, Vec<IOErrorDiagnostic>) {
-        let paths = std::sync::Mutex::new(Vec::new());
-        let diagnostics = std::sync::Mutex::new(Vec::new());
-
-        self.walker.run(|| {
-            Box::new(|entry| {
-                match entry {
-                    Ok(entry) => {
-                        if !self.filter.is_included(entry.path()) {
-                            tracing::debug!("Ignoring not-included path: {}", entry.path());
-                            return WalkState::Skip;
-                        }
-
-                        // Skip over any non python files to avoid creating too many entries in `Files`.
-                        match entry.file_type() {
-                            FileType::File => {
-                                if entry
-                                    .path()
-                                    .extension()
-                                    .and_then(PySourceType::try_from_extension)
-                                    .is_some()
-                                {
-                                    let mut paths = paths.lock().unwrap();
-                                    paths.push(entry.into_path());
-                                }
-                            }
-                            FileType::Directory | FileType::Symlink => {}
-                        }
-                    }
-                    Err(error) => match error.kind() {
-                        ErrorKind::Loop { .. } => {
-                            unreachable!("Loops shouldn't be possible without following symlinks.")
-                        }
-                        ErrorKind::Io { path, err } => {
-                            let mut diagnostics = diagnostics.lock().unwrap();
-                            let error = if let Some(path) = path {
-                                WalkError::IOPathError {
-                                    path: path.clone(),
-                                    error: err.to_string(),
-                                }
-                            } else {
-                                WalkError::IOError {
-                                    error: err.to_string(),
-                                }
-                            };
-
-                            diagnostics.push(IOErrorDiagnostic {
-                                file: None,
-                                error: IOErrorKind::Walk(error),
-                            });
-                        }
-                        ErrorKind::NonUtf8Path { path } => {
-                            diagnostics.lock().unwrap().push(IOErrorDiagnostic {
-                                file: None,
-                                error: IOErrorKind::Walk(WalkError::NonUtf8Path {
-                                    path: path.clone(),
-                                }),
-                            });
-                        }
-                    },
-                }
-
-                WalkState::Continue
-            })
-        });
-
-        (
-            paths.into_inner().unwrap(),
-            diagnostics.into_inner().unwrap(),
-        )
-    }
-
-    pub(crate) fn collect_vec(self, db: &dyn Db) -> (Vec<File>, Vec<IOErrorDiagnostic>) {
-        let (paths, diagnostics) = self.walk_paths();
-
-        (
-            paths
-                .into_iter()
-                .filter_map(move |path| {
-                    // If this returns `None`, then the file was deleted between the `walk_directory` call and now.
-                    // We can ignore this.
-                    system_path_to_file(db.upcast(), &path).ok()
-                })
-                .collect(),
-            diagnostics,
-        )
-    }
-
-    pub(crate) fn collect_set(self, db: &dyn Db) -> (FxHashSet<File>, Vec<IOErrorDiagnostic>) {
-        let (paths, diagnostics) = self.walk_paths();
-
-        let mut files = FxHashSet::with_capacity_and_hasher(paths.len(), FxBuildHasher);
-
-        for path in paths {
-            if let Ok(file) = system_path_to_file(db.upcast(), &path) {
-                files.insert(file);
-            }
-        }
-
-        (files, diagnostics)
-    }
-}
-
-#[derive(Error, Debug, Clone)]
-pub(crate) enum WalkError {
-    #[error("`{path}`: {error}")]
-    IOPathError { path: SystemPathBuf, error: String },
-
-    #[error("Failed to walk project directory: {error}")]
-    IOError { error: String },
-
-    #[error("`{path}` is not a valid UTF-8 path")]
-    NonUtf8Path { path: PathBuf },
-}

crates/red_knot_project/src/watch/project_watcher.rs

@@ -6,7 +6,7 @@ use tracing::info;
 use red_knot_python_semantic::system_module_search_paths;
 use ruff_cache::{CacheKey, CacheKeyHasher};
 use ruff_db::system::{SystemPath, SystemPathBuf};
-use ruff_db::Upcast;
+use ruff_db::{Db as _, Upcast};
 
 use crate::db::{Db, ProjectDatabase};
 use crate::watch::Watcher;
@@ -42,9 +42,9 @@ impl ProjectWatcher {
 
     pub fn update(&mut self, db: &ProjectDatabase) {
         let search_paths: Vec<_> = system_module_search_paths(db.upcast()).collect();
-        let project_path = db.project().root(db);
+        let project_path = db.project().root(db).to_path_buf();
 
-        let new_cache_key = Self::compute_cache_key(project_path, &search_paths);
+        let new_cache_key = Self::compute_cache_key(&project_path, &search_paths);
 
         if self.cache_key == Some(new_cache_key) {
             return;
@@ -68,47 +68,31 @@ impl ProjectWatcher {
 
         self.has_errored_paths = false;
 
-        let config_paths = db
-            .project()
-            .metadata(db)
-            .extra_configuration_paths()
-            .iter()
-            .map(SystemPathBuf::as_path);
-
-        // Watch both the project root and any paths provided by the user on the CLI (removing any redundant nested paths).
-        // This is necessary to observe changes to files that are outside the project root.
-        // We always need to watch the project root to observe changes to its configuration.
-        let included_paths = ruff_db::system::deduplicate_nested_paths(
-            std::iter::once(project_path).chain(
-                db.project()
-                    .included_paths_list(db)
-                    .iter()
-                    .map(SystemPathBuf::as_path),
-            ),
-        );
+        let project_path = db
+            .system()
+            .canonicalize_path(&project_path)
+            .unwrap_or(project_path);
 
         // Find the non-overlapping module search paths and filter out paths that are already covered by the project.
         // Module search paths are already canonicalized.
         let unique_module_paths = ruff_db::system::deduplicate_nested_paths(
             search_paths
                 .into_iter()
-                .filter(|path| !path.starts_with(project_path)),
-        );
+                .filter(|path| !path.starts_with(&project_path)),
+        )
+        .map(SystemPath::to_path_buf);
 
         // Now add the new paths, first starting with the project path and then
-        // adding the library search paths, and finally the paths for configurations.
-        for path in included_paths
-            .chain(unique_module_paths)
-            .chain(config_paths)
-        {
+        // adding the library search paths.
+        for path in std::iter::once(project_path).chain(unique_module_paths) {
             // Log a warning. It's not worth aborting if registering a single folder fails because
             // Ruff otherwise stills works as expected.
-            if let Err(error) = self.watcher.watch(path) {
+            if let Err(error) = self.watcher.watch(&path) {
                 // TODO: Log a user-facing warning.
                 tracing::warn!("Failed to setup watcher for path `{path}`: {error}. You have to restart Ruff after making changes to files under this path or you might see stale results.");
                 self.has_errored_paths = true;
             } else {
-                self.watched_paths.push(path.to_path_buf());
+                self.watched_paths.push(path);
             }
         }
 

crates/red_knot_project/tests/check.rs

@@ -117,7 +117,7 @@ fn run_corpus_tests(pattern: &str) -> anyhow::Result<()> {
         let code = std::fs::read_to_string(source)?;
 
         let mut check_with_file_name = |path: &SystemPath| {
-            memory_fs.write_file_all(path, &code).unwrap();
+            memory_fs.write_file(path, &code).unwrap();
             File::sync_path(&mut db, path);
 
             // this test is only asserting that we can pull every expression type without a panic
@@ -216,17 +216,6 @@ impl SourceOrderVisitor<'_> for PullTypesVisitor<'_> {
                 self.visit_body(&for_stmt.orelse);
                 return;
             }
-            Stmt::With(with_stmt) => {
-                for item in &with_stmt.items {
-                    if let Some(target) = &item.optional_vars {
-                        self.visit_target(target);
-                    }
-                    self.visit_expr(&item.context_expr);
-                }
-
-                self.visit_body(&with_stmt.body);
-                return;
-            }
             Stmt::AnnAssign(_)
             | Stmt::Return(_)
             | Stmt::Delete(_)
@@ -234,6 +223,7 @@ impl SourceOrderVisitor<'_> for PullTypesVisitor<'_> {
             | Stmt::TypeAlias(_)
             | Stmt::While(_)
             | Stmt::If(_)
+            | Stmt::With(_)
             | Stmt::Match(_)
             | Stmt::Raise(_)
             | Stmt::Try(_)
@@ -280,8 +270,6 @@ impl SourceOrderVisitor<'_> for PullTypesVisitor<'_> {
 /// Whether or not the .py/.pyi version of this file is expected to fail
 #[rustfmt::skip]
 const KNOWN_FAILURES: &[(&str, bool, bool)] = &[
-    // related to circular references in nested functions
-    ("crates/ruff_linter/resources/test/fixtures/flake8_return/RET503.py", false, true),
     // related to circular references in class definitions
     ("crates/ruff_linter/resources/test/fixtures/pyflakes/F821_26.py", true, true),
     ("crates/ruff_linter/resources/test/fixtures/pyflakes/F821_27.py", true, true),
@@ -293,9 +281,4 @@ const KNOWN_FAILURES: &[(&str, bool, bool)] = &[
     // related to circular references in f-string annotations (invalid syntax)
     ("crates/ruff_linter/resources/test/fixtures/pyflakes/F821_15.py", true, true),
     ("crates/ruff_linter/resources/test/fixtures/pyflakes/F821_14.py", false, true),
-    // related to circular references in stub type annotations (salsa cycle panic):
-    ("crates/ruff_linter/resources/test/fixtures/pycodestyle/E501_4.py", false, true),
-    ("crates/ruff_linter/resources/test/fixtures/pyflakes/F401_0.py", false, true),
-    ("crates/ruff_linter/resources/test/fixtures/pyflakes/F401_12.py", false, true),
-    ("crates/ruff_linter/resources/test/fixtures/pyflakes/F401_14.py", false, true),
 ];

crates/red_knot_python_semantic/Cargo.toml

@@ -12,9 +12,9 @@ license = { workspace = true }
 
 [dependencies]
 ruff_db = { workspace = true }
-ruff_index = { workspace = true, features = ["salsa"] }
+ruff_index = { workspace = true }
 ruff_macros = { workspace = true }
-ruff_python_ast = { workspace = true, features = ["salsa"] }
+ruff_python_ast = { workspace = true }
 ruff_python_parser = { workspace = true }
 ruff_python_stdlib = { workspace = true }
 ruff_source_file = { workspace = true }
@@ -31,22 +31,19 @@ drop_bomb = { workspace = true }
 indexmap = { workspace = true }
 itertools = { workspace = true }
 ordermap = { workspace = true }
-salsa = { workspace = true, features = ["compact_str"] }
+salsa = { workspace = true }
 thiserror = { workspace = true }
 tracing = { workspace = true }
 rustc-hash = { workspace = true }
 hashbrown = { workspace = true }
-schemars = { workspace = true, optional = true }
 serde = { workspace = true, optional = true }
 smallvec = { workspace = true }
 static_assertions = { workspace = true }
 test-case = { workspace = true }
 memchr = { workspace = true }
-strum = { workspace = true}
-strum_macros = { workspace = true}
 
 [dev-dependencies]
-ruff_db = { workspace = true, features = ["testing", "os"] }
+ruff_db = { workspace = true, features = ["os", "testing"] }
 ruff_python_parser = { workspace = true }
 red_knot_test = { workspace = true }
 red_knot_vendored = { workspace = true }
@@ -59,7 +56,7 @@ quickcheck = { version = "1.0.3", default-features = false }
 quickcheck_macros = { version = "1.0.0" }
 
 [features]
-serde = ["ruff_db/serde", "dep:serde", "ruff_python_ast/serde"]
+serde = ["ruff_db/serde", "dep:serde"]
 
 [lints]
 workspace = true

crates/red_knot_python_semantic/resources/mdtest/annotations/callable.md

@@ -1,195 +0,0 @@
-# Callable
-
-References:
-
-- <https://typing.readthedocs.io/en/latest/spec/callables.html#callable>
-
-TODO: Use `collections.abc` as importing from `typing` is deprecated but this requires support for
-`*` imports. See: <https://docs.python.org/3/library/typing.html#deprecated-aliases>.
-
-## Invalid forms
-
-The `Callable` special form requires _exactly_ two arguments where the first argument is either a
-parameter type list, parameter specification, `typing.Concatenate`, or `...` and the second argument
-is the return type. Here, we explore various invalid forms.
-
-### Empty
-
-A bare `Callable` without any type arguments:
-
-```py
-from typing import Callable
-
-def _(c: Callable):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-### Invalid parameter type argument
-
-When it's not a list:
-
-```py
-from typing import Callable
-
-# error: [invalid-type-form] "The first argument to `Callable` must be either a list of types, ParamSpec, Concatenate, or `...`"
-def _(c: Callable[int, str]):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-Or, when it's a literal type:
-
-```py
-# error: [invalid-type-form] "The first argument to `Callable` must be either a list of types, ParamSpec, Concatenate, or `...`"
-def _(c: Callable[42, str]):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-Or, when one of the parameter type is invalid in the list:
-
-```py
-def _(c: Callable[[int, 42, str, False], None]):
-    # revealed: (int, @Todo(number literal in type expression), str, @Todo(boolean literal in type expression), /) -> None
-    reveal_type(c)
-```
-
-### Missing return type
-
-Using a parameter list:
-
-```py
-from typing import Callable
-
-# error: [invalid-type-form] "Special form `typing.Callable` expected exactly two arguments (parameter types and return type)"
-def _(c: Callable[[int, str]]):
-    reveal_type(c)  # revealed: (int, str, /) -> Unknown
-```
-
-Or, an ellipsis:
-
-```py
-# error: [invalid-type-form] "Special form `typing.Callable` expected exactly two arguments (parameter types and return type)"
-def _(c: Callable[...]):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-### More than two arguments
-
-We can't reliably infer the callable type if there are more then 2 arguments because we don't know
-which argument corresponds to either the parameters or the return type.
-
-```py
-from typing import Callable
-
-# error: [invalid-type-form] "Special form `typing.Callable` expected exactly two arguments (parameter types and return type)"
-def _(c: Callable[[int], str, str]):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-## Simple
-
-A simple `Callable` with multiple parameters and a return type:
-
-```py
-from typing import Callable
-
-def _(c: Callable[[int, str], int]):
-    reveal_type(c)  # revealed: (int, str, /) -> int
-```
-
-## Nested
-
-A nested `Callable` as one of the parameter types:
-
-```py
-from typing import Callable
-
-def _(c: Callable[[Callable[[int], str]], int]):
-    reveal_type(c)  # revealed: ((int, /) -> str, /) -> int
-```
-
-And, as the return type:
-
-```py
-def _(c: Callable[[int, str], Callable[[int], int]]):
-    reveal_type(c)  # revealed: (int, str, /) -> (int, /) -> int
-```
-
-## Gradual form
-
-The `Callable` special form supports the use of `...` in place of the list of parameter types. This
-is a [gradual form] indicating that the type is consistent with any input signature:
-
-```py
-from typing import Callable
-
-def gradual_form(c: Callable[..., str]):
-    reveal_type(c)  # revealed: (...) -> str
-```
-
-## Using `typing.Concatenate`
-
-Using `Concatenate` as the first argument to `Callable`:
-
-```py
-from typing_extensions import Callable, Concatenate
-
-def _(c: Callable[Concatenate[int, str, ...], int]):
-    reveal_type(c)  # revealed: (*args: @Todo(todo signature *args), **kwargs: @Todo(todo signature **kwargs)) -> int
-```
-
-And, as one of the parameter types:
-
-```py
-def _(c: Callable[[Concatenate[int, str, ...], int], int]):
-    reveal_type(c)  # revealed: (*args: @Todo(todo signature *args), **kwargs: @Todo(todo signature **kwargs)) -> int
-```
-
-## Using `typing.ParamSpec`
-
-Using a `ParamSpec` in a `Callable` annotation:
-
-```py
-from typing_extensions import Callable
-
-# TODO: Not an error; remove once `ParamSpec` is supported
-# error: [invalid-type-form]
-def _[**P1](c: Callable[P1, int]):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-And, using the legacy syntax:
-
-```py
-from typing_extensions import ParamSpec
-
-P2 = ParamSpec("P2")
-
-# TODO: Not an error; remove once `ParamSpec` is supported
-# error: [invalid-type-form]
-def _(c: Callable[P2, int]):
-    reveal_type(c)  # revealed: (...) -> Unknown
-```
-
-## Using `typing.Unpack`
-
-Using the unpack operator (`*`):
-
-```py
-from typing_extensions import Callable, TypeVarTuple
-
-Ts = TypeVarTuple("Ts")
-
-def _(c: Callable[[int, *Ts], int]):
-    reveal_type(c)  # revealed: (*args: @Todo(todo signature *args), **kwargs: @Todo(todo signature **kwargs)) -> int
-```
-
-And, using the legacy syntax using `Unpack`:
-
-```py
-from typing_extensions import Unpack
-
-def _(c: Callable[[int, Unpack[Ts]], int]):
-    reveal_type(c)  # revealed: (*args: @Todo(todo signature *args), **kwargs: @Todo(todo signature **kwargs)) -> int
-```
-
-[gradual form]: https://typing.readthedocs.io/en/latest/spec/glossary.html#term-gradual-form

crates/red_knot_python_semantic/resources/mdtest/annotations/deferred.md

@@ -2,9 +2,7 @@
 
 ## Deferred annotations in stubs always resolve
 
-`mod.pyi`:
-
-```pyi
+```pyi path=mod.pyi
 def get_foo() -> Foo: ...
 class Foo: ...
 ```

crates/red_knot_python_semantic/resources/mdtest/annotations/int_float_complex.md

@@ -1,90 +0,0 @@
-# Special cases for int/float/complex in annotations
-
-In order to support common use cases, an annotation of `float` actually means `int | float`, and an
-annotation of `complex` actually means `int | float | complex`. See
-[the specification](https://typing.readthedocs.io/en/latest/spec/special-types.html#special-cases-for-float-and-complex)
-
-## float
-
-An annotation of `float` means `int | float`, so `int` is assignable to it:
-
-```py
-def takes_float(x: float):
-    pass
-
-def passes_int_to_float(x: int):
-    # no error!
-    takes_float(x)
-```
-
-It also applies to variable annotations:
-
-```py
-def assigns_int_to_float(x: int):
-    # no error!
-    y: float = x
-```
-
-It doesn't work the other way around:
-
-```py
-def takes_int(x: int):
-    pass
-
-def passes_float_to_int(x: float):
-    # error: [invalid-argument-type]
-    takes_int(x)
-
-def assigns_float_to_int(x: float):
-    # error: [invalid-assignment]
-    y: int = x
-```
-
-Unlike other type checkers, we choose not to obfuscate this special case by displaying `int | float`
-as just `float`; we display the actual type:
-
-```py
-def f(x: float):
-    reveal_type(x)  # revealed: int | float
-```
-
-## complex
-
-An annotation of `complex` means `int | float | complex`, so `int` and `float` are both assignable
-to it (but not the other way around):
-
-```py
-def takes_complex(x: complex):
-    pass
-
-def passes_to_complex(x: float, y: int):
-    # no errors!
-    takes_complex(x)
-    takes_complex(y)
-
-def assigns_to_complex(x: float, y: int):
-    # no errors!
-    a: complex = x
-    b: complex = y
-
-def takes_int(x: int):
-    pass
-
-def takes_float(x: float):
-    pass
-
-def passes_complex(x: complex):
-    # error: [invalid-argument-type]
-    takes_int(x)
-    # error: [invalid-argument-type]
-    takes_float(x)
-
-def assigns_complex(x: complex):
-    # error: [invalid-assignment]
-    y: int = x
-    # error: [invalid-assignment]
-    z: float = x
-
-def f(x: complex):
-    reveal_type(x)  # revealed: int | float | complex
-```

crates/red_knot_python_semantic/resources/mdtest/annotations/invalid.md

@@ -1,45 +0,0 @@
-# Tests for invalid types in type expressions
-
-## Invalid types are rejected
-
-Many types are illegal in the context of a type expression:
-
-```py
-import typing
-from knot_extensions import AlwaysTruthy, AlwaysFalsy
-from typing_extensions import Literal, Never
-
-def _(
-    a: type[int],
-    b: AlwaysTruthy,
-    c: AlwaysFalsy,
-    d: Literal[True],
-    e: Literal["bar"],
-    f: Literal[b"foo"],
-    g: tuple[int, str],
-    h: Never,
-):
-    def foo(): ...
-    def invalid(
-        i: a,  # error: [invalid-type-form] "Variable of type `type[int]` is not allowed in a type expression"
-        j: b,  # error: [invalid-type-form]
-        k: c,  # error: [invalid-type-form]
-        l: d,  # error: [invalid-type-form]
-        m: e,  # error: [invalid-type-form]
-        n: f,  # error: [invalid-type-form]
-        o: g,  # error: [invalid-type-form]
-        p: h,  # error: [invalid-type-form]
-        q: typing,  # error: [invalid-type-form]
-        r: foo,  # error: [invalid-type-form]
-    ):
-        reveal_type(i)  # revealed: Unknown
-        reveal_type(j)  # revealed: Unknown
-        reveal_type(k)  # revealed: Unknown
-        reveal_type(l)  # revealed: Unknown
-        reveal_type(m)  # revealed: Unknown
-        reveal_type(n)  # revealed: Unknown
-        reveal_type(o)  # revealed: Unknown
-        reveal_type(p)  # revealed: Unknown
-        reveal_type(q)  # revealed: Unknown
-        reveal_type(r)  # revealed: Unknown
-```

crates/red_knot_python_semantic/resources/mdtest/annotations/literal.md

@@ -106,7 +106,7 @@ def union_example(
         Literal["B"],
         Literal[True],
         None,
-    ],
+    ]
 ):
     reveal_type(x)  # revealed: Unknown | Literal[-1, "A", b"A", b"\x00", b"\x07", 0, 1, "B", "foo", "bar", True] | None
 ```
@@ -116,9 +116,7 @@ def union_example(
 Only Literal that is defined in typing and typing_extension modules is detected as the special
 Literal.
 
-`other.pyi`:
-
-```pyi
+```pyi path=other.pyi
 from typing import _SpecialForm
 
 Literal: _SpecialForm

crates/red_knot_python_semantic/resources/mdtest/annotations/literal_string.md

@@ -73,12 +73,12 @@ qux = (foo, bar)
 reveal_type(qux)  # revealed: tuple[Literal["foo"], Literal["bar"]]
 
 # TODO: Infer "LiteralString"
-reveal_type(foo.join(qux))  # revealed: @Todo(return type of decorated function)
+reveal_type(foo.join(qux))  # revealed: @Todo(Attribute access on `StringLiteral` types)
 
 template: LiteralString = "{}, {}"
 reveal_type(template)  # revealed: Literal["{}, {}"]
 # TODO: Infer `LiteralString`
-reveal_type(template.format(foo, bar))  # revealed: @Todo(return type of decorated function)
+reveal_type(template.format(foo, bar))  # revealed: @Todo(Attribute access on `StringLiteral` types)
 ```
 
 ### Assignability

crates/red_knot_python_semantic/resources/mdtest/annotations/stdlib_typing_aliases.md

@@ -70,7 +70,8 @@ import typing
 
 class ListSubclass(typing.List): ...
 
-# revealed: tuple[Literal[ListSubclass], Literal[list], Literal[MutableSequence], Literal[Sequence], Literal[Reversible], Literal[Collection], Literal[Iterable], Literal[Container], @Todo(protocol), Literal[object]]
+# TODO: should have `Generic`, should not have `Unknown`
+# revealed: tuple[Literal[ListSubclass], Literal[list], Unknown, Literal[object]]
 reveal_type(ListSubclass.__mro__)
 
 class DictSubclass(typing.Dict): ...

crates/red_knot_python_semantic/resources/mdtest/annotations/string.md

@@ -116,8 +116,8 @@ MyType = int
 class Aliases:
     MyType = str
 
-    forward: "MyType" = "value"
-    not_forward: MyType = "value"
+    forward: "MyType"
+    not_forward: MyType
 
 reveal_type(Aliases.forward)  # revealed: str
 reveal_type(Aliases.not_forward)  # revealed: str

crates/red_knot_python_semantic/resources/mdtest/annotations/union.md

@@ -9,9 +9,9 @@ from typing import Union
 
 a: Union[int, str]
 a1: Union[int, bool]
-a2: Union[int, Union[bytes, str]]
+a2: Union[int, Union[float, str]]
 a3: Union[int, None]
-a4: Union[Union[bytes, str]]
+a4: Union[Union[float, str]]
 a5: Union[int]
 a6: Union[()]
 
@@ -21,11 +21,11 @@ def f():
     # Since bool is a subtype of int we simplify to int here. But we do allow assigning boolean values (see below).
     # revealed: int
     reveal_type(a1)
-    # revealed: int | bytes | str
+    # revealed: int | float | str
     reveal_type(a2)
     # revealed: int | None
     reveal_type(a3)
-    # revealed: bytes | str
+    # revealed: float | str
     reveal_type(a4)
     # revealed: int
     reveal_type(a5)

crates/red_knot_python_semantic/resources/mdtest/annotations/unsupported_special_forms.md

@@ -18,7 +18,7 @@ def f(*args: Unpack[Ts]) -> tuple[Unpack[Ts]]:
     # TODO: should understand the annotation
     reveal_type(args)  # revealed: tuple
 
-    reveal_type(Alias)  # revealed: @Todo(Invalid or unsupported `KnownInstanceType` in `Type::to_type_expression`)
+    reveal_type(Alias)  # revealed: @Todo(Unsupported or invalid type in a type expression)
 
 def g() -> TypeGuard[int]: ...
 def h() -> TypeIs[int]: ...
@@ -29,13 +29,11 @@ def i(callback: Callable[Concatenate[int, P], R_co], *args: P.args, **kwargs: P.
     # TODO: should understand the annotation
     reveal_type(kwargs)  # revealed: dict
 
-    # TODO: not an error; remove once `call` is implemented for `Callable`
-    # error: [call-non-callable]
     return callback(42, *args, **kwargs)
 
 class Foo:
     def method(self, x: Self):
-        reveal_type(x)  # revealed: @Todo(Invalid or unsupported `KnownInstanceType` in `Type::to_type_expression`)
+        reveal_type(x)  # revealed: @Todo(Unsupported or invalid type in a type expression)
 ```
 
 ## Inheritance

crates/red_knot_python_semantic/resources/mdtest/assignment/annotations.md

@@ -25,9 +25,7 @@ x = "foo"  # error: [invalid-assignment] "Object of type `Literal["foo"]` is not
 
 ## Tuple annotations are understood
 
-`module.py`:
-
-```py
+```py path=module.py
 from typing_extensions import Unpack
 
 a: tuple[()] = ()
@@ -42,9 +40,7 @@ i: tuple[str | int, str | int] = (42, 42)
 j: tuple[str | int] = (42,)
 ```
 
-`script.py`:
-
-```py
+```py path=script.py
 from module import a, b, c, d, e, f, g, h, i, j
 
 reveal_type(a)  # revealed: tuple[()]
@@ -118,7 +114,7 @@ reveal_type(x)  # revealed: Foo
 
 ## Annotations in stub files are deferred
 
-```pyi
+```pyi path=main.pyi
 x: Foo
 
 class Foo: ...
@@ -129,7 +125,7 @@ reveal_type(x)  # revealed: Foo
 
 ## Annotated assignments in stub files are inferred correctly
 
-```pyi
+```pyi path=main.pyi
 x: int = 1
 reveal_type(x) # revealed: Literal[1]
 ```

crates/red_knot_python_semantic/resources/mdtest/assignment/augmented.md

@@ -9,7 +9,7 @@ reveal_type(x)  # revealed: Literal[2]
 
 x = 1.0
 x /= 2
-reveal_type(x)  # revealed: int | float
+reveal_type(x)  # revealed: float
 ```
 
 ## Dunder methods
@@ -24,12 +24,12 @@ x -= 1
 reveal_type(x)  # revealed: str
 
 class C:
-    def __iadd__(self, other: str) -> int:
-        return 1
+    def __iadd__(self, other: str) -> float:
+        return 1.0
 
 x = C()
 x += "Hello"
-reveal_type(x)  # revealed: int
+reveal_type(x)  # revealed: float
 ```
 
 ## Unsupported types
@@ -40,7 +40,7 @@ class C:
         return 42
 
 x = C()
-# error: [unsupported-operator] "Operator `-=` is unsupported between objects of type `C` and `Literal[1]`"
+# error: [invalid-argument-type]
 x -= 1
 
 reveal_type(x)  # revealed: int
@@ -75,7 +75,8 @@ def _(flag: bool):
 
     f = Foo()
 
-    # error: [unsupported-operator] "Operator `+=` is unsupported between objects of type `Foo` and `Literal["Hello, world!"]`"
+    # TODO: We should emit an `unsupported-operator` error here, possibly with the information
+    # that `Foo.__iadd__` may be unbound as additional context.
     f += "Hello, world!"
 
     reveal_type(f)  # revealed: int | Unknown
@@ -129,10 +130,10 @@ def _(flag: bool):
     if flag:
         f = Foo()
     else:
-        f = 42
+        f = 42.0
     f += 12
 
-    reveal_type(f)  # revealed: str | Literal[54]
+    reveal_type(f)  # revealed: str | float
 ```
 
 ## Partially bound target union with `__add__`

crates/red_knot_python_semantic/resources/mdtest/binary/booleans.md

@@ -56,7 +56,7 @@ def _(a: bool):
         reveal_type(x - a)  # revealed: int
         reveal_type(x * a)  # revealed: int
         reveal_type(x // a)  # revealed: int
-        reveal_type(x / a)  # revealed: int | float
+        reveal_type(x / a)  # revealed: float
         reveal_type(x % a)  # revealed: int
 
     def rhs_is_int(x: int):
@@ -64,7 +64,7 @@ def _(a: bool):
         reveal_type(a - x)  # revealed: int
         reveal_type(a * x)  # revealed: int
         reveal_type(a // x)  # revealed: int
-        reveal_type(a / x)  # revealed: int | float
+        reveal_type(a / x)  # revealed: float
         reveal_type(a % x)  # revealed: int
 
     def lhs_is_bool(x: bool):
@@ -72,7 +72,7 @@ def _(a: bool):
         reveal_type(x - a)  # revealed: int
         reveal_type(x * a)  # revealed: int
         reveal_type(x // a)  # revealed: int
-        reveal_type(x / a)  # revealed: int | float
+        reveal_type(x / a)  # revealed: float
         reveal_type(x % a)  # revealed: int
 
     def rhs_is_bool(x: bool):
@@ -80,7 +80,7 @@ def _(a: bool):
         reveal_type(a - x)  # revealed: int
         reveal_type(a * x)  # revealed: int
         reveal_type(a // x)  # revealed: int
-        reveal_type(a / x)  # revealed: int | float
+        reveal_type(a / x)  # revealed: float
         reveal_type(a % x)  # revealed: int
 
     def both_are_bool(x: bool, y: bool):
@@ -88,6 +88,6 @@ def _(a: bool):
         reveal_type(x - y)  # revealed: int
         reveal_type(x * y)  # revealed: int
         reveal_type(x // y)  # revealed: int
-        reveal_type(x / y)  # revealed: int | float
+        reveal_type(x / y)  # revealed: float
         reveal_type(x % y)  # revealed: int
 ```

crates/red_knot_python_semantic/resources/mdtest/binary/custom.md

@@ -3,8 +3,6 @@
 ## Class instances
 
 ```py
-from typing import Literal
-
 class Yes:
     def __add__(self, other) -> Literal["+"]:
         return "+"
@@ -138,8 +136,6 @@ reveal_type(No() // Yes())  # revealed: Unknown
 ## Subclass reflections override superclass dunders
 
 ```py
-from typing import Literal
-
 class Yes:
     def __add__(self, other) -> Literal["+"]:
         return "+"
@@ -298,8 +294,6 @@ itself. (For these operators to work on the class itself, they would have to be
 class's type, i.e. `type`.)
 
 ```py
-from typing import Literal
-
 class Yes:
     def __add__(self, other) -> Literal["+"]:
         return "+"
@@ -318,8 +312,6 @@ reveal_type(No + No)  # revealed: Unknown
 ## Subclass
 
 ```py
-from typing import Literal
-
 class Yes:
     def __add__(self, other) -> Literal["+"]:
         return "+"

crates/red_knot_python_semantic/resources/mdtest/binary/instances.md

@@ -244,7 +244,10 @@ class B:
     def __rsub__(self, other: A) -> B:
         return B()
 
-reveal_type(A() - B())  # revealed: B
+# TODO: this should be `B` (the return annotation of `B.__rsub__`),
+# because `A.__sub__` is annotated as only accepting `A`,
+# but `B.__rsub__` will accept `A`.
+reveal_type(A() - B())  # revealed: A
 ```
 
 ## Callable instances as dunders
@@ -259,38 +262,32 @@ class A:
 class B:
     __add__ = A()
 
+# TODO: this could be `int` if we declare `B.__add__` using a `Callable` type
 reveal_type(B() + B())  # revealed: Unknown | int
 ```
 
-Note that we union with `Unknown` here because `__add__` is not declared. We do infer just `int` if
-the callable is declared:
-
-```py
-class B2:
-    __add__: A = A()
-
-reveal_type(B2() + B2())  # revealed: int
-```
-
 ## Integration test: numbers from typeshed
 
-We get less precise results from binary operations on float/complex literals due to the special case
-for annotations of `float` or `complex`, which applies also to return annotations for typeshed
-dunder methods. Perhaps we could have a special-case on the special-case, to exclude these typeshed
-return annotations from the widening, and preserve a bit more precision here?
-
 ```py
-reveal_type(3j + 3.14)  # revealed: int | float | complex
-reveal_type(4.2 + 42)  # revealed: int | float
-reveal_type(3j + 3)  # revealed: int | float | complex
-reveal_type(3.14 + 3j)  # revealed: int | float | complex
-reveal_type(42 + 4.2)  # revealed: int | float
-reveal_type(3 + 3j)  # revealed: int | float | complex
+reveal_type(3j + 3.14)  # revealed: complex
+reveal_type(4.2 + 42)  # revealed: float
+reveal_type(3j + 3)  # revealed: complex
+
+# TODO should be complex, need to check arg type and fall back to `rhs.__radd__`
+reveal_type(3.14 + 3j)  # revealed: float
+
+# TODO should be float, need to check arg type and fall back to `rhs.__radd__`
+reveal_type(42 + 4.2)  # revealed: int
+
+# TODO should be complex, need to check arg type and fall back to `rhs.__radd__`
+reveal_type(3 + 3j)  # revealed: int
 
 def _(x: bool, y: int):
     reveal_type(x + y)  # revealed: int
-    reveal_type(4.2 + x)  # revealed: int | float
-    reveal_type(y + 4.12)  # revealed: int | float
+    reveal_type(4.2 + x)  # revealed: float
+
+    # TODO should be float, need to check arg type and fall back to `rhs.__radd__`
+    reveal_type(y + 4.12)  # revealed: int
 ```
 
 ## With literal types
@@ -307,12 +304,13 @@ class A:
         return self
 
 reveal_type(A() + 1)  # revealed: A
-reveal_type(1 + A())  # revealed: A
+# TODO should be `A` since `int.__add__` doesn't support `A` instances
+reveal_type(1 + A())  # revealed: int
 
 reveal_type(A() + "foo")  # revealed: A
 # TODO should be `A` since `str.__add__` doesn't support `A` instances
 # TODO overloads
-reveal_type("foo" + A())  # revealed: @Todo(return type of decorated function)
+reveal_type("foo" + A())  # revealed: @Todo(return type)
 
 reveal_type(A() + b"foo")  # revealed: A
 # TODO should be `A` since `bytes.__add__` doesn't support `A` instances
@@ -320,7 +318,7 @@ reveal_type(b"foo" + A())  # revealed: bytes
 
 reveal_type(A() + ())  # revealed: A
 # TODO this should be `A`, since `tuple.__add__` doesn't support `A` instances
-reveal_type(() + A())  # revealed: @Todo(return type of decorated function)
+reveal_type(() + A())  # revealed: @Todo(return type)
 
 literal_string_instance = "foo" * 1_000_000_000
 # the test is not testing what it's meant to be testing if this isn't a `LiteralString`:
@@ -329,7 +327,7 @@ reveal_type(literal_string_instance)  # revealed: LiteralString
 reveal_type(A() + literal_string_instance)  # revealed: A
 # TODO should be `A` since `str.__add__` doesn't support `A` instances
 # TODO overloads
-reveal_type(literal_string_instance + A())  # revealed: @Todo(return type of decorated function)
+reveal_type(literal_string_instance + A())  # revealed: @Todo(return type)
 ```
 
 ## Operations involving instances of classes inheriting from `Any`
@@ -357,20 +355,6 @@ class Y(Foo): ...
 reveal_type(X() + Y())  # revealed: int
 ```
 
-## Operations involving types with invalid `__bool__` methods
-
-<!-- snapshot-diagnostics -->
-
-```py
-class NotBoolable:
-    __bool__ = 3
-
-a = NotBoolable()
-
-# error: [unsupported-bool-conversion]
-10 and a and True
-```
-
 ## Unsupported
 
 ### Dunder as instance attribute

crates/red_knot_python_semantic/resources/mdtest/binary/integers.md

@@ -10,15 +10,16 @@ reveal_type(-3 // 3)  # revealed: Literal[-1]
 reveal_type(-3 / 3)  # revealed: float
 reveal_type(5 % 3)  # revealed: Literal[2]
 
-# error: [unsupported-operator] "Operator `+` is unsupported between objects of type `Literal[2]` and `Literal["f"]`"
-reveal_type(2 + "f")  # revealed: Unknown
+# TODO: We don't currently verify that the actual parameter to int.__add__ matches the declared
+# formal parameter type.
+reveal_type(2 + "f")  # revealed: int
 
 def lhs(x: int):
     reveal_type(x + 1)  # revealed: int
     reveal_type(x - 4)  # revealed: int
     reveal_type(x * -1)  # revealed: int
     reveal_type(x // 3)  # revealed: int
-    reveal_type(x / 3)  # revealed: int | float
+    reveal_type(x / 3)  # revealed: float
     reveal_type(x % 3)  # revealed: int
 
 def rhs(x: int):
@@ -26,7 +27,7 @@ def rhs(x: int):
     reveal_type(3 - x)  # revealed: int
     reveal_type(3 * x)  # revealed: int
     reveal_type(-3 // x)  # revealed: int
-    reveal_type(-3 / x)  # revealed: int | float
+    reveal_type(-3 / x)  # revealed: float
     reveal_type(5 % x)  # revealed: int
 
 def both(x: int):
@@ -34,7 +35,7 @@ def both(x: int):
     reveal_type(x - x)  # revealed: int
     reveal_type(x * x)  # revealed: int
     reveal_type(x // x)  # revealed: int
-    reveal_type(x / x)  # revealed: int | float
+    reveal_type(x / x)  # revealed: float
     reveal_type(x % x)  # revealed: int
 ```
 
@@ -50,9 +51,9 @@ reveal_type(1 ** (largest_u32 + 1))  # revealed: int
 reveal_type(2**largest_u32)  # revealed: int
 
 def variable(x: int):
-    reveal_type(x**2)  # revealed: @Todo(return type of decorated function)
-    reveal_type(2**x)  # revealed: @Todo(return type of decorated function)
-    reveal_type(x**x)  # revealed: @Todo(return type of decorated function)
+    reveal_type(x**2)  # revealed: @Todo(return type)
+    reveal_type(2**x)  # revealed: @Todo(return type)
+    reveal_type(x**x)  # revealed: @Todo(return type)
 ```
 
 ## Division by Zero
@@ -79,20 +80,24 @@ c = 3 % 0  # error: "Cannot reduce object of type `Literal[3]` modulo zero"
 reveal_type(c)  # revealed: int
 
 # error: "Cannot divide object of type `int` by zero"
-reveal_type(int() / 0)  # revealed: int | float
+# revealed: float
+reveal_type(int() / 0)
 
 # error: "Cannot divide object of type `Literal[1]` by zero"
-reveal_type(1 / False)  # revealed: float
+# revealed: float
+reveal_type(1 / False)
 # error: [division-by-zero] "Cannot divide object of type `Literal[True]` by zero"
 True / False
 # error: [division-by-zero] "Cannot divide object of type `Literal[True]` by zero"
 bool(1) / False
 
 # error: "Cannot divide object of type `float` by zero"
-reveal_type(1.0 / 0)  # revealed: int | float
+# revealed: float
+reveal_type(1.0 / 0)
 
 class MyInt(int): ...
 
 # No error for a subclass of int
-reveal_type(MyInt(3) / 0)  # revealed: int | float
+# revealed: float
+reveal_type(MyInt(3) / 0)
 ```

crates/red_knot_python_semantic/resources/mdtest/boundness_declaredness/public.md

@@ -1,6 +1,6 @@
 # Boundness and declaredness: public uses
 
-This document demonstrates how type-inference and diagnostics work for *public* uses of a symbol,
+This document demonstrates how type-inference and diagnostics works for *public* uses of a symbol,
 that is, a use of a symbol from another scope. If a symbol has a declared type in its local scope
 (e.g. `int`), we use that as the symbol's "public type" (the type of the symbol from the perspective
 of other scopes) even if there is a more precise local inferred type for the symbol (`Literal[1]`).
@@ -34,28 +34,20 @@ In particular, we should raise errors in the "possibly-undeclared-and-unbound" a
 ### Declared and bound
 
 If a symbol has a declared type (`int`), we use that even if there is a more precise inferred type
-(`Literal[1]`), or a conflicting inferred type (`str` vs. `Literal[2]` below):
+(`Literal[1]`), or a conflicting inferred type (`Literal[2]`):
 
-`mod.py`:
+```py path=mod.py
+x: int = 1
 
-```py
-from typing import Any
-
-def any() -> Any: ...
-
-a: int = 1
-b: str = 2  # error: [invalid-assignment]
-c: Any = 3
-d: int = any()
+# error: [invalid-assignment]
+y: str = 2
 ```
 
 ```py
-from mod import a, b, c, d
+from mod import x, y
 
-reveal_type(a)  # revealed: int
-reveal_type(b)  # revealed: str
-reveal_type(c)  # revealed: Any
-reveal_type(d)  # revealed: int
+reveal_type(x)  # revealed: int
+reveal_type(y)  # revealed: str
 ```
 
 ### Declared and possibly unbound
@@ -63,33 +55,22 @@ reveal_type(d)  # revealed: int
 If a symbol is declared and *possibly* unbound, we trust that other module and use the declared type
 without raising an error.
 
-`mod.py`:
-
-```py
-from typing import Any
-
-def any() -> Any: ...
+```py path=mod.py
 def flag() -> bool: ...
 
-a: int
-b: str
-c: Any
-d: int
-
+x: int
+y: str
 if flag:
-    a = 1
-    b = 2  # error: [invalid-assignment]
-    c = 3
-    d = any()
+    x = 1
+    # error: [invalid-assignment]
+    y = 2
 ```
 
 ```py
-from mod import a, b, c, d
+from mod import x, y
 
-reveal_type(a)  # revealed: int
-reveal_type(b)  # revealed: str
-reveal_type(c)  # revealed: Any
-reveal_type(d)  # revealed: int
+reveal_type(x)  # revealed: int
+reveal_type(y)  # revealed: str
 ```
 
 ### Declared and unbound
@@ -97,20 +78,14 @@ reveal_type(d)  # revealed: int
 Similarly, if a symbol is declared but unbound, we do not raise an error. We trust that this symbol
 is available somehow and simply use the declared type.
 
-`mod.py`:
-
-```py
-from typing import Any
-
-a: int
-b: Any
+```py path=mod.py
+x: int
 ```
 
 ```py
-from mod import a, b
+from mod import x
 
-reveal_type(a)  # revealed: int
-reveal_type(b)  # revealed: Any
+reveal_type(x)  # revealed: int
 ```
 
 ## Possibly undeclared
@@ -120,70 +95,61 @@ reveal_type(b)  # revealed: Any
 If a symbol is possibly undeclared but definitely bound, we use the union of the declared and
 inferred types:
 
-`mod.py`:
-
-```py
+```py path=mod.py
 from typing import Any
 
-def any() -> Any: ...
 def flag() -> bool: ...
 
-a = 1
-b = 2
-c = 3
-d = any()
+x = 1
+y = 2
+z = 3
 if flag():
-    a: int
-    b: Any
-    c: str  # error: [invalid-declaration]
-    d: int
+    x: int
+    y: Any
+    # error: [invalid-declaration]
+    z: str
 ```
 
 ```py
-from mod import a, b, c, d
+from mod import x, y, z
 
-reveal_type(a)  # revealed: int
-reveal_type(b)  # revealed: Literal[2] | Any
-reveal_type(c)  # revealed: Literal[3] | Unknown
-reveal_type(d)  # revealed: Any | int
+reveal_type(x)  # revealed: int
+reveal_type(y)  # revealed: Literal[2] | Any
+reveal_type(z)  # revealed: Literal[3] | Unknown
 
-# External modifications of `a` that violate the declared type are not allowed:
+# External modifications of `x` that violate the declared type are not allowed:
 # error: [invalid-assignment]
-a = None
+x = None
 ```
 
 ### Possibly undeclared and possibly unbound
 
 If a symbol is possibly undeclared and possibly unbound, we also use the union of the declared and
 inferred types. This case is interesting because the "possibly declared" definition might not be the
-same as the "possibly bound" definition (symbol `b`). Note that we raise a `possibly-unbound-import`
-error for both `a` and `b`:
-
-`mod.py`:
-
-```py
-from typing import Any
+same as the "possibly bound" definition (symbol `y`). Note that we raise a `possibly-unbound-import`
+error for both `x` and `y`:
 
+```py path=mod.py
 def flag() -> bool: ...
 
 if flag():
-    a: Any = 1
-    b = 2
+    x: Any = 1
+    y = 2
 else:
-    b: str
+    y: str
 ```
 
 ```py
 # error: [possibly-unbound-import]
 # error: [possibly-unbound-import]
-from mod import a, b
+from mod import x, y
 
-reveal_type(a)  # revealed: Literal[1] | Any
-reveal_type(b)  # revealed: Literal[2] | str
+reveal_type(x)  # revealed: Literal[1] | Any
+reveal_type(y)  # revealed: Literal[2] | str
 
-# External modifications of `b` that violate the declared type are not allowed:
+# External modifications of `y` that violate the declared type are not allowed:
 # error: [invalid-assignment]
-b = None
+y = None
 ```
 
 ### Possibly undeclared and unbound
@@ -191,53 +157,40 @@ b = None
 If a symbol is possibly undeclared and definitely unbound, we currently do not raise an error. This
 seems inconsistent when compared to the case just above.
 
-`mod.py`:
-
-```py
+```py path=mod.py
 def flag() -> bool: ...
 
 if flag():
-    a: int
+    x: int
 ```
 
 ```py
 # TODO: this should raise an error. Once we fix this, update the section description and the table
 # on top of this document.
-from mod import a
+from mod import x
 
-reveal_type(a)  # revealed: int
+reveal_type(x)  # revealed: int
 
-# External modifications to `a` that violate the declared type are not allowed:
+# External modifications to `x` that violate the declared type are not allowed:
 # error: [invalid-assignment]
-a = None
+x = None
 ```
 
 ## Undeclared
 
 ### Undeclared but bound
 
-If a symbol is *undeclared*, we use the union of `Unknown` with the inferred type. Note that we
-treat this case differently from the case where a symbol is implicitly declared with `Unknown`,
-possibly due to the usage of an unknown name in the annotation:
-
-`mod.py`:
-
-```py
-# Undeclared:
-a = 1
-
-# Implicitly declared with `Unknown`, due to the usage of an unknown name in the annotation:
-b: SomeUnknownName = 1  # error: [unresolved-reference]
+```py path=mod.py
+x = 1
 ```
 
 ```py
-from mod import a, b
+from mod import x
 
-reveal_type(a)  # revealed: Unknown | Literal[1]
-reveal_type(b)  # revealed: Unknown
+reveal_type(x)  # revealed: Unknown | Literal[1]
 
-# All external modifications of `a` are allowed:
-a = None
+# All external modifications of `x` are allowed:
+x = None
 ```
 
 ### Undeclared and possibly unbound
@@ -245,45 +198,39 @@ a = None
 If a symbol is undeclared and *possibly* unbound, we currently do not raise an error. This seems
 inconsistent when compared to the "possibly-undeclared-and-possibly-unbound" case.
 
-`mod.py`:
-
-```py
+```py path=mod.py
 def flag() -> bool: ...
 
 if flag:
-    a = 1
-    b: SomeUnknownName = 1  # error: [unresolved-reference]
+    x = 1
 ```
 
 ```py
 # TODO: this should raise an error. Once we fix this, update the section description and the table
 # on top of this document.
-from mod import a, b
+from mod import x
 
-reveal_type(a)  # revealed: Unknown | Literal[1]
-reveal_type(b)  # revealed: Unknown
+reveal_type(x)  # revealed: Unknown | Literal[1]
 
-# All external modifications of `a` are allowed:
-a = None
+# All external modifications of `x` are allowed:
+x = None
 ```
 
 ### Undeclared and unbound
 
 If a symbol is undeclared *and* unbound, we infer `Unknown` and raise an error.
 
-`mod.py`:
-
-```py
+```py path=mod.py
 if False:
-    a: int = 1
+    x: int = 1
 ```
 
 ```py
 # error: [unresolved-import]
-from mod import a
+from mod import x
 
-reveal_type(a)  # revealed: Unknown
+reveal_type(x)  # revealed: Unknown
 
 # Modifications allowed in this case:
-a = None
+x = None
 ```

crates/red_knot_python_semantic/resources/mdtest/call/builtins.md

@@ -1,37 +0,0 @@
-# Calling builtins
-
-## `bool` with incorrect arguments
-
-```py
-class NotBool:
-    __bool__ = None
-
-# TODO: We should emit an `invalid-argument` error here for `2` because `bool` only takes one argument.
-bool(1, 2)
-
-# TODO: We should emit an `unsupported-bool-conversion` error here because the argument doesn't implement `__bool__` correctly.
-bool(NotBool())
-```
-
-## Calls to `type()`
-
-A single-argument call to `type()` returns an object that has the argument's meta-type. (This is
-tested more extensively in `crates/red_knot_python_semantic/resources/mdtest/attributes.md`,
-alongside the tests for the `__class__` attribute.)
-
-```py
-reveal_type(type(1))  # revealed: Literal[int]
-```
-
-But a three-argument call to type creates a dynamic instance of the `type` class:
-
-```py
-reveal_type(type("Foo", (), {}))  # revealed: type
-```
-
-Other numbers of arguments are invalid (TODO -- these should emit a diagnostic)
-
-```py
-type("Foo", ())
-type("Foo", (), {}, weird_other_arg=42)
-```

crates/red_knot_python_semantic/resources/mdtest/call/callable_instance.md

@@ -4,14 +4,14 @@
 
 ```py
 class Multiplier:
-    def __init__(self, factor: int):
+    def __init__(self, factor: float):
         self.factor = factor
 
-    def __call__(self, number: int) -> int:
+    def __call__(self, number: float) -> float:
         return number * self.factor
 
-a = Multiplier(2)(3)
-reveal_type(a)  # revealed: int
+a = Multiplier(2.0)(3.0)
+reveal_type(a)  # revealed: float
 
 class Unit: ...
 
@@ -52,7 +52,7 @@ class NonCallable:
     __call__ = 1
 
 a = NonCallable()
-# error: [call-non-callable] "Object of type `Literal[1]` is not callable"
+# error: "Object of type `Unknown | Literal[1]` is not callable (due to union element `Literal[1]`)"
 reveal_type(a())  # revealed: Unknown
 ```
 
@@ -67,8 +67,8 @@ def _(flag: bool):
             def __call__(self) -> int: ...
 
     a = NonCallable()
-    # error: [call-non-callable] "Object of type `Literal[1]` is not callable"
-    reveal_type(a())  # revealed: int | Unknown
+    # error: "Object of type `Literal[1] | Literal[__call__]` is not callable (due to union element `Literal[1]`)"
+    reveal_type(a())  # revealed: Unknown | int
 ```
 
 ## Call binding errors
@@ -82,7 +82,7 @@ class C:
 
 c = C()
 
-# error: 15 [invalid-argument-type] "Object of type `Literal["foo"]` cannot be assigned to parameter 2 (`x`) of bound method `__call__`; expected type `int`"
+# error: 15 [invalid-argument-type] "Object of type `Literal["foo"]` cannot be assigned to parameter 2 (`x`) of function `__call__`; expected type `int`"
 reveal_type(c("foo"))  # revealed: int
 ```
 
@@ -96,29 +96,6 @@ class C:
 
 c = C()
 
-# error: 13 [invalid-argument-type] "Object of type `C` cannot be assigned to parameter 1 (`self`) of bound method `__call__`; expected type `int`"
+# error: 13 [invalid-argument-type] "Object of type `C` cannot be assigned to parameter 1 (`self`) of function `__call__`; expected type `int`"
 reveal_type(c())  # revealed: int
 ```
-
-## Union over callables
-
-### Possibly unbound `__call__`
-
-```py
-def outer(cond1: bool):
-    class Test:
-        if cond1:
-            def __call__(self): ...
-
-    class Other:
-        def __call__(self): ...
-
-    def inner(cond2: bool):
-        if cond2:
-            a = Test()
-        else:
-            a = Other()
-
-            # error: [call-non-callable] "Object of type `Test` is not callable (possibly unbound `__call__` method)"
-        a()
-```

crates/red_knot_python_semantic/resources/mdtest/call/dunder.md

@@ -1,219 +0,0 @@
-# Dunder calls
-
-## Introduction
-
-This test suite explains and documents how dunder methods are looked up and called. Throughout the
-document, we use `__getitem__` as an example, but the same principles apply to other dunder methods.
-
-Dunder methods are implicitly called when using certain syntax. For example, the index operator
-`obj[key]` calls the `__getitem__` method under the hood. Exactly *how* a dunder method is looked up
-and called works slightly different from regular methods. Dunder methods are not looked up on `obj`
-directly, but rather on `type(obj)`. But in many ways, they still *act* as if they were called on
-`obj` directly. If the `__getitem__` member of `type(obj)` is a descriptor, it is called with `obj`
-as the `instance` argument to `__get__`. A desugared version of `obj[key]` is roughly equivalent to
-`getitem_desugared(obj, key)` as defined below:
-
-```py
-from typing import Any
-
-def find_name_in_mro(typ: type, name: str) -> Any:
-    # See implementation in https://docs.python.org/3/howto/descriptor.html#invocation-from-an-instance
-    pass
-
-def getitem_desugared(obj: object, key: object) -> object:
-    getitem_callable = find_name_in_mro(type(obj), "__getitem__")
-    if hasattr(getitem_callable, "__get__"):
-        getitem_callable = getitem_callable.__get__(obj, type(obj))
-
-    return getitem_callable(key)
-```
-
-In the following tests, we demonstrate that we implement this behavior correctly.
-
-## Operating on class objects
-
-If we invoke a dunder method on a class, it is looked up on the *meta* class, since any class is an
-instance of its metaclass:
-
-```py
-class Meta(type):
-    def __getitem__(cls, key: int) -> str:
-        return str(key)
-
-class DunderOnMetaclass(metaclass=Meta):
-    pass
-
-reveal_type(DunderOnMetaclass[0])  # revealed: str
-```
-
-If the dunder method is only present on the class itself, it will not be called:
-
-```py
-class ClassWithNormalDunder:
-    def __getitem__(self, key: int) -> str:
-        return str(key)
-
-# error: [non-subscriptable]
-ClassWithNormalDunder[0]
-```
-
-## Operating on instances
-
-When invoking a dunder method on an instance of a class, it is looked up on the class:
-
-```py
-class ClassWithNormalDunder:
-    def __getitem__(self, key: int) -> str:
-        return str(key)
-
-class_with_normal_dunder = ClassWithNormalDunder()
-
-reveal_type(class_with_normal_dunder[0])  # revealed: str
-```
-
-Which can be demonstrated by trying to attach a dunder method to an instance, which will not work:
-
-```py
-def external_getitem(instance, key: int) -> str:
-    return str(key)
-
-class ThisFails:
-    def __init__(self):
-        self.__getitem__ = external_getitem
-
-this_fails = ThisFails()
-
-# error: [non-subscriptable] "Cannot subscript object of type `ThisFails` with no `__getitem__` method"
-reveal_type(this_fails[0])  # revealed: Unknown
-```
-
-However, the attached dunder method *can* be called if accessed directly:
-
-```py
-reveal_type(this_fails.__getitem__(this_fails, 0))  # revealed: Unknown | str
-```
-
-The instance-level method is also not called when the class-level method is present:
-
-```py
-def external_getitem1(instance, key) -> str:
-    return "a"
-
-def external_getitem2(key) -> int:
-    return 1
-
-def _(flag: bool):
-    class ThisFails:
-        if flag:
-            __getitem__ = external_getitem1
-
-        def __init__(self):
-            self.__getitem__ = external_getitem2
-
-    this_fails = ThisFails()
-
-    # error: [call-possibly-unbound-method]
-    reveal_type(this_fails[0])  # revealed: Unknown | str
-```
-
-## When the dunder is not a method
-
-A dunder can also be a non-method callable:
-
-```py
-class SomeCallable:
-    def __call__(self, key: int) -> str:
-        return str(key)
-
-class ClassWithNonMethodDunder:
-    __getitem__: SomeCallable = SomeCallable()
-
-class_with_callable_dunder = ClassWithNonMethodDunder()
-
-reveal_type(class_with_callable_dunder[0])  # revealed: str
-```
-
-## Dunders are looked up using the descriptor protocol
-
-Here, we demonstrate that the descriptor protocol is invoked when looking up a dunder method. Note
-that the `instance` argument is on object of type `ClassWithDescriptorDunder`:
-
-```py
-from __future__ import annotations
-
-class SomeCallable:
-    def __call__(self, key: int) -> str:
-        return str(key)
-
-class Descriptor:
-    def __get__(self, instance: ClassWithDescriptorDunder, owner: type[ClassWithDescriptorDunder]) -> SomeCallable:
-        return SomeCallable()
-
-class ClassWithDescriptorDunder:
-    __getitem__: Descriptor = Descriptor()
-
-class_with_descriptor_dunder = ClassWithDescriptorDunder()
-
-reveal_type(class_with_descriptor_dunder[0])  # revealed: str
-```
-
-## Dunders can not be overwritten on instances
-
-If we attempt to overwrite a dunder method on an instance, it does not affect the behavior of
-implicit dunder calls:
-
-```py
-class C:
-    def __getitem__(self, key: int) -> str:
-        return str(key)
-
-    def f(self):
-        # TODO: This should emit an `invalid-assignment` diagnostic once we understand the type of `self`
-        self.__getitem__ = None
-
-# This is still fine, and simply calls the `__getitem__` method on the class
-reveal_type(C()[0])  # revealed: str
-```
-
-## Calling a union of dunder methods
-
-```py
-def _(flag: bool):
-    class C:
-        if flag:
-            def __getitem__(self, key: int) -> str:
-                return str(key)
-        else:
-            def __getitem__(self, key: int) -> bytes:
-                return key
-
-    c = C()
-    reveal_type(c[0])  # revealed: str | bytes
-
-    if flag:
-        class D:
-            def __getitem__(self, key: int) -> str:
-                return str(key)
-
-    else:
-        class D:
-            def __getitem__(self, key: int) -> bytes:
-                return key
-
-    d = D()
-    reveal_type(d[0])  # revealed: str | bytes
-```
-
-## Calling a possibly-unbound dunder method
-
-```py
-def _(flag: bool):
-    class C:
-        if flag:
-            def __getitem__(self, key: int) -> str:
-                return str(key)
-
-    c = C()
-    # error: [call-possibly-unbound-method]
-    reveal_type(c[0])  # revealed: str
-```

crates/red_knot_python_semantic/resources/mdtest/call/function.md

@@ -44,7 +44,7 @@ def bar() -> str:
     return "bar"
 
 # TODO: should reveal `int`, as the decorator replaces `bar` with `foo`
-reveal_type(bar())  # revealed: @Todo(return type of decorated function)
+reveal_type(bar())  # revealed: @Todo(return type)
 ```
 
 ## Invalid callable
@@ -278,10 +278,10 @@ proper diagnostics in case of missing or superfluous arguments.
 from typing_extensions import reveal_type
 
 # error: [missing-argument] "No argument provided for required parameter `obj` of function `reveal_type`"
-reveal_type()
+reveal_type()  # revealed: Unknown
 
 # error: [too-many-positional-arguments] "Too many positional arguments to function `reveal_type`: expected 1, got 2"
-reveal_type(1, 2)
+reveal_type(1, 2)  # revealed: Literal[1]
 ```
 
 ### `static_assert`
@@ -290,6 +290,7 @@ reveal_type(1, 2)
 from knot_extensions import static_assert
 
 # error: [missing-argument] "No argument provided for required parameter `condition` of function `static_assert`"
+# error: [static-assert-error]
 static_assert()
 
 # error: [too-many-positional-arguments] "Too many positional arguments to function `static_assert`: expected 2, got 3"

crates/red_knot_python_semantic/resources/mdtest/call/getattr_static.md

@@ -1,150 +0,0 @@
-# `inspect.getattr_static`
-
-## Basic usage
-
-`inspect.getattr_static` is a function that returns attributes of an object without invoking the
-descriptor protocol (for caveats, see the [official documentation]).
-
-Consider the following example:
-
-```py
-import inspect
-
-class Descriptor:
-    def __get__(self, instance, owner) -> str:
-        return "a"
-
-class C:
-    normal: int = 1
-    descriptor: Descriptor = Descriptor()
-```
-
-If we access attributes on an instance of `C` as usual, the descriptor protocol is invoked, and we
-get a type of `str` for the `descriptor` attribute:
-
-```py
-c = C()
-
-reveal_type(c.normal)  # revealed: int
-reveal_type(c.descriptor)  # revealed: str
-```
-
-However, if we use `inspect.getattr_static`, we can see the underlying `Descriptor` type:
-
-```py
-reveal_type(inspect.getattr_static(c, "normal"))  # revealed: int
-reveal_type(inspect.getattr_static(c, "descriptor"))  # revealed: Descriptor
-```
-
-For non-existent attributes, a default value can be provided:
-
-```py
-reveal_type(inspect.getattr_static(C, "normal", "default-arg"))  # revealed: int
-reveal_type(inspect.getattr_static(C, "non_existent", "default-arg"))  # revealed: Literal["default-arg"]
-```
-
-When a non-existent attribute is accessed without a default value, the runtime raises an
-`AttributeError`. We could emit a diagnostic for this case, but that is currently not supported:
-
-```py
-# TODO: we could emit a diagnostic here
-reveal_type(inspect.getattr_static(C, "non_existent"))  # revealed: Never
-```
-
-We can access attributes on objects of all kinds:
-
-```py
-import sys
-
-reveal_type(inspect.getattr_static(sys, "platform"))  # revealed: LiteralString
-reveal_type(inspect.getattr_static(inspect, "getattr_static"))  # revealed: Literal[getattr_static]
-
-reveal_type(inspect.getattr_static(1, "real"))  # revealed: Literal[real]
-```
-
-(Implicit) instance attributes can also be accessed through `inspect.getattr_static`:
-
-```py
-class D:
-    def __init__(self) -> None:
-        self.instance_attr: int = 1
-
-reveal_type(inspect.getattr_static(D(), "instance_attr"))  # revealed: int
-```
-
-And attributes on metaclasses can be accessed when probing the class:
-
-```py
-class Meta(type):
-    attr: int = 1
-
-class E(metaclass=Meta): ...
-
-reveal_type(inspect.getattr_static(E, "attr"))  # revealed: int
-```
-
-Metaclass attributes can not be added when probing an instance of the class:
-
-```py
-reveal_type(inspect.getattr_static(E(), "attr", "non_existent"))  # revealed: Literal["non_existent"]
-```
-
-## Error cases
-
-We can only infer precise types if the attribute is a literal string. In all other cases, we fall
-back to `Any`:
-
-```py
-import inspect
-
-class C:
-    x: int = 1
-
-def _(attr_name: str):
-    reveal_type(inspect.getattr_static(C(), attr_name))  # revealed: Any
-    reveal_type(inspect.getattr_static(C(), attr_name, 1))  # revealed: Any
-```
-
-But we still detect errors in the number or type of arguments:
-
-```py
-# error: [missing-argument] "No arguments provided for required parameters `obj`, `attr` of function `getattr_static`"
-inspect.getattr_static()
-
-# error: [missing-argument] "No argument provided for required parameter `attr`"
-inspect.getattr_static(C())
-
-# error: [invalid-argument-type] "Object of type `Literal[1]` cannot be assigned to parameter 2 (`attr`) of function `getattr_static`; expected type `str`"
-inspect.getattr_static(C(), 1)
-
-# error: [too-many-positional-arguments] "Too many positional arguments to function `getattr_static`: expected 3, got 4"
-inspect.getattr_static(C(), "x", "default-arg", "one too many")
-```
-
-## Possibly unbound attributes
-
-```py
-import inspect
-
-def _(flag: bool):
-    class C:
-        if flag:
-            x: int = 1
-
-    reveal_type(inspect.getattr_static(C, "x", "default"))  # revealed: int | Literal["default"]
-```
-
-## Gradual types
-
-```py
-import inspect
-from typing import Any
-
-def _(a: Any, tuple_of_any: tuple[Any]):
-    reveal_type(inspect.getattr_static(a, "x", "default"))  # revealed: Any | Literal["default"]
-
-    # TODO: Ideally, this would just be `Literal[index]`
-    reveal_type(inspect.getattr_static(tuple_of_any, "index", "default"))  # revealed: Literal[index] | Literal["default"]
-```
-
-[official documentation]: https://docs.python.org/3/library/inspect.html#inspect.getattr_static

crates/red_knot_python_semantic/resources/mdtest/call/methods.md

@@ -1,432 +0,0 @@
-# Methods
-
-## Background: Functions as descriptors
-
-> Note: See also this related section in the descriptor guide: [Functions and methods].
-
-Say we have a simple class `C` with a function definition `f` inside its body:
-
-```py
-class C:
-    def f(self, x: int) -> str:
-        return "a"
-```
-
-Whenever we access the `f` attribute through the class object itself (`C.f`) or through an instance
-(`C().f`), this access happens via the descriptor protocol. Functions are (non-data) descriptors
-because they implement a `__get__` method. This is crucial in making sure that method calls work as
-expected. In general, the signature of the `__get__` method in the descriptor protocol is
-`__get__(self, instance, owner)`. The `self` argument is the descriptor object itself (`f`). The
-passed value for the `instance` argument depends on whether the attribute is accessed from the class
-object (in which case it is `None`), or from an instance (in which case it is the instance of type
-`C`). The `owner` argument is the class itself (`C` of type `Literal[C]`). To summarize:
-
-- `C.f` is equivalent to `getattr_static(C, "f").__get__(None, C)`
-- `C().f` is equivalent to `getattr_static(C, "f").__get__(C(), C)`
-
-Here, `inspect.getattr_static` is used to bypass the descriptor protocol and directly access the
-function attribute. The way the special `__get__` method *on functions* works is as follows. In the
-former case, if the `instance` argument is `None`, `__get__` simply returns the function itself. In
-the latter case, it returns a *bound method* object:
-
-```py
-from inspect import getattr_static
-
-reveal_type(getattr_static(C, "f"))  # revealed: Literal[f]
-
-reveal_type(getattr_static(C, "f").__get__)  # revealed: <method-wrapper `__get__` of `f`>
-
-reveal_type(getattr_static(C, "f").__get__(None, C))  # revealed: Literal[f]
-reveal_type(getattr_static(C, "f").__get__(C(), C))  # revealed: <bound method `f` of `C`>
-```
-
-In conclusion, this is why we see the following two types when accessing the `f` attribute on the
-class object `C` and on an instance `C()`:
-
-```py
-reveal_type(C.f)  # revealed: Literal[f]
-reveal_type(C().f)  # revealed: <bound method `f` of `C`>
-```
-
-A bound method is a callable object that contains a reference to the `instance` that it was called
-on (can be inspected via `__self__`), and the function object that it refers to (can be inspected
-via `__func__`):
-
-```py
-bound_method = C().f
-
-reveal_type(bound_method.__self__)  # revealed: C
-reveal_type(bound_method.__func__)  # revealed: Literal[f]
-```
-
-When we call the bound method, the `instance` is implicitly passed as the first argument (`self`):
-
-```py
-reveal_type(C().f(1))  # revealed: str
-reveal_type(bound_method(1))  # revealed: str
-```
-
-When we call the function object itself, we need to pass the `instance` explicitly:
-
-```py
-C.f(1)  # error: [missing-argument]
-
-reveal_type(C.f(C(), 1))  # revealed: str
-```
-
-When we access methods from derived classes, they will be bound to instances of the derived class:
-
-```py
-class D(C):
-    pass
-
-reveal_type(D().f)  # revealed: <bound method `f` of `D`>
-```
-
-If we access an attribute on a bound method object itself, it will defer to `types.MethodType`:
-
-```py
-reveal_type(bound_method.__hash__)  # revealed: <bound method `__hash__` of `MethodType`>
-```
-
-If an attribute is not available on the bound method object, it will be looked up on the underlying
-function object. We model this explicitly, which means that we can access `__kwdefaults__` on bound
-methods, even though it is not available on `types.MethodType`:
-
-```py
-reveal_type(bound_method.__kwdefaults__)  # revealed: @Todo(generics) | None
-```
-
-## Basic method calls on class objects and instances
-
-```py
-class Base:
-    def method_on_base(self, x: int | None) -> str:
-        return "a"
-
-class Derived(Base):
-    def method_on_derived(self, x: bytes) -> tuple[int, str]:
-        return (1, "a")
-
-reveal_type(Base().method_on_base(1))  # revealed: str
-reveal_type(Base.method_on_base(Base(), 1))  # revealed: str
-
-Base().method_on_base("incorrect")  # error: [invalid-argument-type]
-Base().method_on_base()  # error: [missing-argument]
-Base().method_on_base(1, 2)  # error: [too-many-positional-arguments]
-
-reveal_type(Derived().method_on_base(1))  # revealed: str
-reveal_type(Derived().method_on_derived(b"abc"))  # revealed: tuple[int, str]
-reveal_type(Derived.method_on_base(Derived(), 1))  # revealed: str
-reveal_type(Derived.method_on_derived(Derived(), b"abc"))  # revealed: tuple[int, str]
-```
-
-## Method calls on literals
-
-### Boolean literals
-
-```py
-reveal_type(True.bit_length())  # revealed: int
-reveal_type(True.as_integer_ratio())  # revealed: tuple[int, Literal[1]]
-```
-
-### Integer literals
-
-```py
-reveal_type((42).bit_length())  # revealed: int
-```
-
-### String literals
-
-```py
-reveal_type("abcde".find("abc"))  # revealed: int
-reveal_type("foo".encode(encoding="utf-8"))  # revealed: bytes
-
-"abcde".find(123)  # error: [invalid-argument-type]
-```
-
-### Bytes literals
-
-```py
-reveal_type(b"abcde".startswith(b"abc"))  # revealed: bool
-```
-
-## Method calls on `LiteralString`
-
-```py
-from typing_extensions import LiteralString
-
-def f(s: LiteralString) -> None:
-    reveal_type(s.find("a"))  # revealed: int
-```
-
-## Method calls on `tuple`
-
-```py
-def f(t: tuple[int, str]) -> None:
-    reveal_type(t.index("a"))  # revealed: int
-```
-
-## Method calls on unions
-
-```py
-from typing import Any
-
-class A:
-    def f(self) -> int:
-        return 1
-
-class B:
-    def f(self) -> str:
-        return "a"
-
-def f(a_or_b: A | B, any_or_a: Any | A):
-    reveal_type(a_or_b.f)  # revealed: <bound method `f` of `A`> | <bound method `f` of `B`>
-    reveal_type(a_or_b.f())  # revealed: int | str
-
-    reveal_type(any_or_a.f)  # revealed: Any | <bound method `f` of `A`>
-    reveal_type(any_or_a.f())  # revealed: Any | int
-```
-
-## Method calls on `KnownInstance` types
-
-```toml
-[environment]
-python-version = "3.12"
-```
-
-```py
-type IntOrStr = int | str
-
-reveal_type(IntOrStr.__or__)  # revealed: <bound method `__or__` of `typing.TypeAliasType`>
-```
-
-## Error cases: Calling `__get__` for methods
-
-The `__get__` method on `types.FunctionType` has the following overloaded signature in typeshed:
-
-```py
-from types import FunctionType, MethodType
-from typing import overload
-
-@overload
-def __get__(self, instance: None, owner: type, /) -> FunctionType: ...
-@overload
-def __get__(self, instance: object, owner: type | None = None, /) -> MethodType: ...
-```
-
-Here, we test that this signature is enforced correctly:
-
-```py
-from inspect import getattr_static
-
-class C:
-    def f(self, x: int) -> str:
-        return "a"
-
-method_wrapper = getattr_static(C, "f").__get__
-
-reveal_type(method_wrapper)  # revealed: <method-wrapper `__get__` of `f`>
-
-# All of these are fine:
-method_wrapper(C(), C)
-method_wrapper(C())
-method_wrapper(C(), None)
-method_wrapper(None, C)
-
-# Passing `None` without an `owner` argument is an
-# error: [missing-argument] "No argument provided for required parameter `owner`"
-method_wrapper(None)
-
-# Passing something that is not assignable to `type` as the `owner` argument is an
-# error: [invalid-argument-type] "Object of type `Literal[1]` cannot be assigned to parameter 2 (`owner`) of method wrapper `__get__` of function `f`; expected type `type`"
-method_wrapper(None, 1)
-
-# Passing `None` as the `owner` argument when `instance` is `None` is an
-# error: [invalid-argument-type] "Object of type `None` cannot be assigned to parameter 2 (`owner`) of method wrapper `__get__` of function `f`; expected type `type`"
-method_wrapper(None, None)
-
-# Calling `__get__` without any arguments is an
-# error: [missing-argument] "No argument provided for required parameter `instance`"
-method_wrapper()
-
-# Calling `__get__` with too many positional arguments is an
-# error: [too-many-positional-arguments] "Too many positional arguments to method wrapper `__get__` of function `f`: expected 2, got 3"
-method_wrapper(C(), C, "one too many")
-```
-
-## Fallback to metaclass
-
-When a method is accessed on a class object, it is looked up on the metaclass if it is not found on
-the class itself. This also creates a bound method that is bound to the class object itself:
-
-```py
-from __future__ import annotations
-
-class Meta(type):
-    def f(cls, arg: int) -> str:
-        return "a"
-
-class C(metaclass=Meta):
-    pass
-
-reveal_type(C.f)  # revealed: <bound method `f` of `Literal[C]`>
-reveal_type(C.f(1))  # revealed: str
-```
-
-The method `f` can not be accessed from an instance of the class:
-
-```py
-# error: [unresolved-attribute] "Type `C` has no attribute `f`"
-C().f
-```
-
-A metaclass function can be shadowed by a method on the class:
-
-```py
-from typing import Any, Literal
-
-class D(metaclass=Meta):
-    def f(arg: int) -> Literal["a"]:
-        return "a"
-
-reveal_type(D.f(1))  # revealed: Literal["a"]
-```
-
-If the class method is possibly unbound, we union the return types:
-
-```py
-def flag() -> bool:
-    return True
-
-class E(metaclass=Meta):
-    if flag():
-        def f(arg: int) -> Any:
-            return "a"
-
-reveal_type(E.f(1))  # revealed: str | Any
-```
-
-## `@classmethod`
-
-### Basic
-
-When a `@classmethod` attribute is accessed, it returns a bound method object, even when accessed on
-the class object itself:
-
-```py
-from __future__ import annotations
-
-class C:
-    @classmethod
-    def f(cls: type[C], x: int) -> str:
-        return "a"
-
-reveal_type(C.f)  # revealed: <bound method `f` of `Literal[C]`>
-reveal_type(C().f)  # revealed: <bound method `f` of `type[C]`>
-```
-
-The `cls` method argument is then implicitly passed as the first argument when calling the method:
-
-```py
-reveal_type(C.f(1))  # revealed: str
-reveal_type(C().f(1))  # revealed: str
-```
-
-When the class method is called incorrectly, we detect it:
-
-```py
-C.f("incorrect")  # error: [invalid-argument-type]
-C.f()  # error: [missing-argument]
-C.f(1, 2)  # error: [too-many-positional-arguments]
-```
-
-If the `cls` parameter is wrongly annotated, we emit an error at the call site:
-
-```py
-class D:
-    @classmethod
-    def f(cls: D):
-        # This function is wrongly annotated, it should be `type[D]` instead of `D`
-        pass
-
-# error: [invalid-argument-type] "Object of type `Literal[D]` cannot be assigned to parameter 1 (`cls`) of bound method `f`; expected type `D`"
-D.f()
-```
-
-When a class method is accessed on a derived class, it is bound to that derived class:
-
-```py
-class Derived(C):
-    pass
-
-reveal_type(Derived.f)  # revealed: <bound method `f` of `Literal[Derived]`>
-reveal_type(Derived().f)  # revealed: <bound method `f` of `type[Derived]`>
-
-reveal_type(Derived.f(1))  # revealed: str
-reveal_type(Derived().f(1))  # revealed: str
-```
-
-### Accessing the classmethod as a static member
-
-Accessing a `@classmethod`-decorated function at runtime returns a `classmethod` object. We
-currently don't model this explicitly:
-
-```py
-from inspect import getattr_static
-
-class C:
-    @classmethod
-    def f(cls): ...
-
-reveal_type(getattr_static(C, "f"))  # revealed: Literal[f]
-reveal_type(getattr_static(C, "f").__get__)  # revealed: <method-wrapper `__get__` of `f`>
-```
-
-But we correctly model how the `classmethod` descriptor works:
-
-```py
-reveal_type(getattr_static(C, "f").__get__(None, C))  # revealed: <bound method `f` of `Literal[C]`>
-reveal_type(getattr_static(C, "f").__get__(C(), C))  # revealed: <bound method `f` of `Literal[C]`>
-reveal_type(getattr_static(C, "f").__get__(C()))  # revealed: <bound method `f` of `type[C]`>
-```
-
-The `owner` argument takes precedence over the `instance` argument:
-
-```py
-reveal_type(getattr_static(C, "f").__get__("dummy", C))  # revealed: <bound method `f` of `Literal[C]`>
-```
-
-### Classmethods mixed with other decorators
-
-When a `@classmethod` is additionally decorated with another decorator, it is still treated as a
-class method:
-
-```py
-from __future__ import annotations
-
-def does_nothing[T](f: T) -> T:
-    return f
-
-class C:
-    @classmethod
-    @does_nothing
-    def f1(cls: type[C], x: int) -> str:
-        return "a"
-
-    @does_nothing
-    @classmethod
-    def f2(cls: type[C], x: int) -> str:
-        return "a"
-
-# TODO: We do not support decorators yet (only limited special cases). Eventually,
-# these should all return `str`:
-
-reveal_type(C.f1(1))  # revealed: @Todo(return type of decorated function)
-reveal_type(C().f1(1))  # revealed: @Todo(return type of decorated function)
-
-reveal_type(C.f2(1))  # revealed: @Todo(return type of decorated function)
-reveal_type(C().f2(1))  # revealed: @Todo(return type of decorated function)
-```
-
-[functions and methods]: https://docs.python.org/3/howto/descriptor.html#functions-and-methods

crates/red_knot_python_semantic/resources/mdtest/call/never.md

@@ -1,12 +0,0 @@
-# Never is callable
-
-The type `Never` is callable with an arbitrary set of arguments. The result is always `Never`.
-
-```py
-from typing_extensions import Never
-
-def f(never: Never):
-    reveal_type(never())  # revealed: Never
-    reveal_type(never(1))  # revealed: Never
-    reveal_type(never(1, "a", never, x=None))  # revealed: Never
-```

crates/red_knot_python_semantic/resources/mdtest/call/subclass_of.md

@@ -1,50 +0,0 @@
-# Call `type[...]`
-
-## Single class
-
-### Trivial constructor
-
-```py
-class C: ...
-
-def _(subclass_of_c: type[C]):
-    reveal_type(subclass_of_c())  # revealed: C
-```
-
-### Non-trivial constructor
-
-```py
-class C:
-    def __init__(self, x: int): ...
-
-def _(subclass_of_c: type[C]):
-    reveal_type(subclass_of_c(1))  # revealed: C
-
-    # TODO: Those should all be errors
-    reveal_type(subclass_of_c("a"))  # revealed: C
-    reveal_type(subclass_of_c())  # revealed: C
-    reveal_type(subclass_of_c(1, 2))  # revealed: C
-```
-
-## Dynamic base
-
-```py
-from typing import Any
-from knot_extensions import Unknown
-
-def _(subclass_of_any: type[Any], subclass_of_unknown: type[Unknown]):
-    reveal_type(subclass_of_any())  # revealed: Any
-    reveal_type(subclass_of_any("any", "args", 1, 2))  # revealed: Any
-    reveal_type(subclass_of_unknown())  # revealed: Unknown
-    reveal_type(subclass_of_unknown("any", "args", 1, 2))  # revealed: Unknown
-```
-
-## Unions of classes
-
-```py
-class A: ...
-class B: ...
-
-def _(subclass_of_ab: type[A | B]):
-    reveal_type(subclass_of_ab())  # revealed: A | B
-```

crates/red_knot_python_semantic/resources/mdtest/call/union.md

@@ -39,8 +39,8 @@ def _(flag: bool):
     else:
         def f() -> int:
             return 1
-    x = f()  # error: [call-non-callable] "Object of type `Literal[1]` is not callable"
-    reveal_type(x)  # revealed: int | Unknown
+    x = f()  # error: "Object of type `Literal[1] | Literal[f]` is not callable (due to union element `Literal[1]`)"
+    reveal_type(x)  # revealed: Unknown | int
 ```
 
 ## Multiple non-callable elements in a union
@@ -56,9 +56,8 @@ def _(flag: bool, flag2: bool):
     else:
         def f() -> int:
             return 1
-    # TODO we should mention all non-callable elements of the union
-    # error: [call-non-callable] "Object of type `Literal[1]` is not callable"
-    # revealed: int | Unknown
+    # error: "Object of type `Literal[1, "foo"] | Literal[f]` is not callable (due to union elements Literal[1], Literal["foo"])"
+    # revealed: Unknown | int
     reveal_type(f())
 ```
 
@@ -73,74 +72,6 @@ def _(flag: bool):
     else:
         f = "foo"
 
-    x = f()  # error: [call-non-callable] "Object of type `Literal[1, "foo"]` is not callable"
-    reveal_type(x)  # revealed: Unknown
-```
-
-## Mismatching signatures
-
-Calling a union where the arguments don't match the signature of all variants.
-
-```py
-def f1(a: int) -> int: ...
-def f2(a: str) -> str: ...
-def _(flag: bool):
-    if flag:
-        f = f1
-    else:
-        f = f2
-
-    # error: [invalid-argument-type] "Object of type `Literal[3]` cannot be assigned to parameter 1 (`a`) of function `f2`; expected type `str`"
-    x = f(3)
-    reveal_type(x)  # revealed: int | str
-```
-
-## Any non-callable variant
-
-```py
-def f1(a: int): ...
-def _(flag: bool):
-    if flag:
-        f = f1
-    else:
-        f = "This is a string literal"
-
-    # error: [call-non-callable] "Object of type `Literal["This is a string literal"]` is not callable"
-    x = f(3)
-    reveal_type(x)  # revealed: Unknown
-```
-
-## Union of binding errors
-
-```py
-def f1(): ...
-def f2(): ...
-def _(flag: bool):
-    if flag:
-        f = f1
-    else:
-        f = f2
-
-    # TODO: we should show all errors from the union, not arbitrarily pick one union element
-    # error: [too-many-positional-arguments] "Too many positional arguments to function `f1`: expected 0, got 1"
-    x = f(3)
-    reveal_type(x)  # revealed: Unknown
-```
-
-## One not-callable, one wrong argument
-
-```py
-class C: ...
-
-def f1(): ...
-def _(flag: bool):
-    if flag:
-        f = f1
-    else:
-        f = C()
-
-    # TODO: we should either show all union errors here, or prioritize the not-callable error
-    # error: [too-many-positional-arguments] "Too many positional arguments to function `f1`: expected 0, got 1"
-    x = f(3)
+    x = f()  # error: "Object of type `Literal[1, "foo"]` is not callable"
     reveal_type(x)  # revealed: Unknown
 ```

crates/red_knot_python_semantic/resources/mdtest/comparison/instances/membership_test.md

@@ -21,9 +21,8 @@ class A:
 
 reveal_type("hello" in A())  # revealed: bool
 reveal_type("hello" not in A())  # revealed: bool
-# error: [unsupported-operator] "Operator `in` is not supported for types `int` and `A`, in comparing `Literal[42]` with `A`"
+# TODO: should emit diagnostic, need to check arg type, will fail
 reveal_type(42 in A())  # revealed: bool
-# error: [unsupported-operator] "Operator `not in` is not supported for types `int` and `A`, in comparing `Literal[42]` with `A`"
 reveal_type(42 not in A())  # revealed: bool
 ```
 
@@ -127,9 +126,9 @@ class A:
 
 reveal_type(CheckContains() in A())  # revealed: bool
 
-# error: [unsupported-operator] "Operator `in` is not supported for types `CheckIter` and `A`"
+# TODO: should emit diagnostic, need to check arg type,
+# should not fall back to __iter__ or __getitem__
 reveal_type(CheckIter() in A())  # revealed: bool
-# error: [unsupported-operator] "Operator `in` is not supported for types `CheckGetItem` and `A`"
 reveal_type(CheckGetItem() in A())  # revealed: bool
 
 class B:
@@ -155,50 +154,7 @@ class A:
     def __getitem__(self, key: str) -> str:
         return "foo"
 
-# error: [unsupported-operator] "Operator `in` is not supported for types `int` and `A`, in comparing `Literal[42]` with `A`"
+# TODO should emit a diagnostic
 reveal_type(42 in A())  # revealed: bool
-# error: [unsupported-operator] "Operator `in` is not supported for types `str` and `A`, in comparing `Literal["hello"]` with `A`"
 reveal_type("hello" in A())  # revealed: bool
 ```
-
-## Return type that doesn't implement `__bool__` correctly
-
-`in` and `not in` operations will fail at runtime if the object on the right-hand side of the
-operation has a `__contains__` method that returns a type which is not convertible to `bool`. This
-is because of the way these operations are handled by the Python interpreter at runtime. If we
-assume that `y` is an object that has a `__contains__` method, the Python expression `x in y`
-desugars to a `contains(y, x)` call, where `contains` looks something like this:
-
-```ignore
-def contains(y, x):
-    return bool(type(y).__contains__(y, x))
-```
-
-where the `bool()` conversion itself implicitly calls `__bool__` under the hood.
-
-TODO: Ideally the message would explain to the user what's wrong. E.g,
-
-```ignore
-error: [operator] cannot use `in` operator on object of type `WithContains`
-    note: This is because the `in` operator implicitly calls `WithContains.__contains__`, but `WithContains.__contains__` is invalidly defined
-    note: `WithContains.__contains__` is invalidly defined because it returns an instance of `NotBoolable`, which cannot be evaluated in a boolean context
-    note: `NotBoolable` cannot be evaluated in a boolean context because its `__bool__` attribute is not callable
-```
-
-It may also be more appropriate to use `unsupported-operator` as the error code.
-
-<!-- snapshot-diagnostics -->
-
-```py
-class NotBoolable:
-    __bool__ = 3
-
-class WithContains:
-    def __contains__(self, item) -> NotBoolable:
-        return NotBoolable()
-
-# error: [unsupported-bool-conversion]
-10 in WithContains()
-# error: [unsupported-bool-conversion]
-10 not in WithContains()
-```

crates/red_knot_python_semantic/resources/mdtest/comparison/instances/rich_comparison.md

@@ -16,38 +16,31 @@ most common case involves implementing these methods for the same type:
 ```py
 from __future__ import annotations
 
-class EqReturnType: ...
-class NeReturnType: ...
-class LtReturnType: ...
-class LeReturnType: ...
-class GtReturnType: ...
-class GeReturnType: ...
-
 class A:
-    def __eq__(self, other: A) -> EqReturnType:
-        return EqReturnType()
+    def __eq__(self, other: A) -> int:
+        return 42
 
-    def __ne__(self, other: A) -> NeReturnType:
-        return NeReturnType()
+    def __ne__(self, other: A) -> float:
+        return 42.0
 
-    def __lt__(self, other: A) -> LtReturnType:
-        return LtReturnType()
+    def __lt__(self, other: A) -> str:
+        return "42"
 
-    def __le__(self, other: A) -> LeReturnType:
-        return LeReturnType()
+    def __le__(self, other: A) -> bytes:
+        return b"42"
 
-    def __gt__(self, other: A) -> GtReturnType:
-        return GtReturnType()
+    def __gt__(self, other: A) -> list:
+        return [42]
 
-    def __ge__(self, other: A) -> GeReturnType:
-        return GeReturnType()
+    def __ge__(self, other: A) -> set:
+        return {42}
 
-reveal_type(A() == A())  # revealed: EqReturnType
-reveal_type(A() != A())  # revealed: NeReturnType
-reveal_type(A() < A())  # revealed: LtReturnType
-reveal_type(A() <= A())  # revealed: LeReturnType
-reveal_type(A() > A())  # revealed: GtReturnType
-reveal_type(A() >= A())  # revealed: GeReturnType
+reveal_type(A() == A())  # revealed: int
+reveal_type(A() != A())  # revealed: float
+reveal_type(A() < A())  # revealed: str
+reveal_type(A() <= A())  # revealed: bytes
+reveal_type(A() > A())  # revealed: list
+reveal_type(A() >= A())  # revealed: set
 ```
 
 ## Rich Comparison Dunder Implementations for Other Class
@@ -58,40 +51,33 @@ type:
 ```py
 from __future__ import annotations
 
-class EqReturnType: ...
-class NeReturnType: ...
-class LtReturnType: ...
-class LeReturnType: ...
-class GtReturnType: ...
-class GeReturnType: ...
-
 class A:
-    def __eq__(self, other: B) -> EqReturnType:
-        return EqReturnType()
+    def __eq__(self, other: B) -> int:
+        return 42
 
-    def __ne__(self, other: B) -> NeReturnType:
-        return NeReturnType()
+    def __ne__(self, other: B) -> float:
+        return 42.0
 
-    def __lt__(self, other: B) -> LtReturnType:
-        return LtReturnType()
+    def __lt__(self, other: B) -> str:
+        return "42"
 
-    def __le__(self, other: B) -> LeReturnType:
-        return LeReturnType()
+    def __le__(self, other: B) -> bytes:
+        return b"42"
 
-    def __gt__(self, other: B) -> GtReturnType:
-        return GtReturnType()
+    def __gt__(self, other: B) -> list:
+        return [42]
 
-    def __ge__(self, other: B) -> GeReturnType:
-        return GeReturnType()
+    def __ge__(self, other: B) -> set:
+        return {42}
 
 class B: ...
 
-reveal_type(A() == B())  # revealed: EqReturnType
-reveal_type(A() != B())  # revealed: NeReturnType
-reveal_type(A() < B())  # revealed: LtReturnType
-reveal_type(A() <= B())  # revealed: LeReturnType
-reveal_type(A() > B())  # revealed: GtReturnType
-reveal_type(A() >= B())  # revealed: GeReturnType
+reveal_type(A() == B())  # revealed: int
+reveal_type(A() != B())  # revealed: float
+reveal_type(A() < B())  # revealed: str
+reveal_type(A() <= B())  # revealed: bytes
+reveal_type(A() > B())  # revealed: list
+reveal_type(A() >= B())  # revealed: set
 ```
 
 ## Reflected Comparisons
@@ -103,64 +89,58 @@ these methods will be ignored here because they require a mismatched operand typ
 ```py
 from __future__ import annotations
 
-class EqReturnType: ...
-class NeReturnType: ...
-class LtReturnType: ...
-class LeReturnType: ...
-class GtReturnType: ...
-class GeReturnType: ...
-
 class A:
-    def __eq__(self, other: B) -> EqReturnType:
-        return EqReturnType()
+    def __eq__(self, other: B) -> int:
+        return 42
 
-    def __ne__(self, other: B) -> NeReturnType:
-        return NeReturnType()
+    def __ne__(self, other: B) -> float:
+        return 42.0
 
-    def __lt__(self, other: B) -> LtReturnType:
-        return LtReturnType()
+    def __lt__(self, other: B) -> str:
+        return "42"
 
-    def __le__(self, other: B) -> LeReturnType:
-        return LeReturnType()
+    def __le__(self, other: B) -> bytes:
+        return b"42"
 
-    def __gt__(self, other: B) -> GtReturnType:
-        return GtReturnType()
+    def __gt__(self, other: B) -> list:
+        return [42]
 
-    def __ge__(self, other: B) -> GeReturnType:
-        return GeReturnType()
-
-class Unrelated: ...
+    def __ge__(self, other: B) -> set:
+        return {42}
 
 class B:
     # To override builtins.object.__eq__ and builtins.object.__ne__
     # TODO these should emit an invalid override diagnostic
-    def __eq__(self, other: Unrelated) -> B:
+    def __eq__(self, other: str) -> B:
         return B()
 
-    def __ne__(self, other: Unrelated) -> B:
+    def __ne__(self, other: str) -> B:
         return B()
 
+# TODO: should be `int` and `float`.
+# Need to check arg type and fall back to `rhs.__eq__` and `rhs.__ne__`.
+#
 # Because `object.__eq__` and `object.__ne__` accept `object` in typeshed,
 # this can only happen with an invalid override of these methods,
 # but we still support it.
-reveal_type(B() == A())  # revealed: EqReturnType
-reveal_type(B() != A())  # revealed: NeReturnType
+reveal_type(B() == A())  # revealed: B
+reveal_type(B() != A())  # revealed: B
 
-reveal_type(B() < A())  # revealed: GtReturnType
-reveal_type(B() <= A())  # revealed: GeReturnType
+reveal_type(B() < A())  # revealed: list
+reveal_type(B() <= A())  # revealed: set
 
-reveal_type(B() > A())  # revealed: LtReturnType
-reveal_type(B() >= A())  # revealed: LeReturnType
+reveal_type(B() > A())  # revealed: str
+reveal_type(B() >= A())  # revealed: bytes
 
 class C:
-    def __gt__(self, other: C) -> EqReturnType:
+    def __gt__(self, other: C) -> int:
         return 42
 
-    def __ge__(self, other: C) -> NeReturnType:
-        return NeReturnType()
+    def __ge__(self, other: C) -> float:
+        return 42.0
 
-reveal_type(C() < C())  # revealed: EqReturnType
-reveal_type(C() <= C())  # revealed: NeReturnType
+reveal_type(C() < C())  # revealed: int
+reveal_type(C() <= C())  # revealed: float
 ```
 
 ## Reflected Comparisons with Subclasses
@@ -172,13 +152,6 @@ than `A`.
 ```py
 from __future__ import annotations
 
-class EqReturnType: ...
-class NeReturnType: ...
-class LtReturnType: ...
-class LeReturnType: ...
-class GtReturnType: ...
-class GeReturnType: ...
-
 class A:
     def __eq__(self, other: A) -> A:
         return A()
@@ -199,32 +172,32 @@ class A:
         return A()
 
 class B(A):
-    def __eq__(self, other: A) -> EqReturnType:
-        return EqReturnType()
+    def __eq__(self, other: A) -> int:
+        return 42
 
-    def __ne__(self, other: A) -> NeReturnType:
-        return NeReturnType()
+    def __ne__(self, other: A) -> float:
+        return 42.0
 
-    def __lt__(self, other: A) -> LtReturnType:
-        return LtReturnType()
+    def __lt__(self, other: A) -> str:
+        return "42"
 
-    def __le__(self, other: A) -> LeReturnType:
-        return LeReturnType()
+    def __le__(self, other: A) -> bytes:
+        return b"42"
 
-    def __gt__(self, other: A) -> GtReturnType:
-        return GtReturnType()
+    def __gt__(self, other: A) -> list:
+        return [42]
 
-    def __ge__(self, other: A) -> GeReturnType:
-        return GeReturnType()
+    def __ge__(self, other: A) -> set:
+        return {42}
 
-reveal_type(A() == B())  # revealed: EqReturnType
-reveal_type(A() != B())  # revealed: NeReturnType
+reveal_type(A() == B())  # revealed: int
+reveal_type(A() != B())  # revealed: float
 
-reveal_type(A() < B())  # revealed: GtReturnType
-reveal_type(A() <= B())  # revealed: GeReturnType
+reveal_type(A() < B())  # revealed: list
+reveal_type(A() <= B())  # revealed: set
 
-reveal_type(A() > B())  # revealed: LtReturnType
-reveal_type(A() >= B())  # revealed: LeReturnType
+reveal_type(A() > B())  # revealed: str
+reveal_type(A() >= B())  # revealed: bytes
 ```
 
 ## Reflected Comparisons with Subclass But Falls Back to LHS
@@ -249,8 +222,9 @@ class B(A):
     def __gt__(self, other: int) -> B:
         return B()
 
-reveal_type(A() < B())  # revealed: A
-reveal_type(A() > B())  # revealed: A
+# TODO: should be `A`, need to check argument type and fall back to LHS method
+reveal_type(A() < B())  # revealed: B
+reveal_type(A() > B())  # revealed: B
 ```
 
 ## Operations involving instances of classes inheriting from `Any`
@@ -298,8 +272,9 @@ class A:
     def __ne__(self, other: int) -> A:
         return A()
 
-reveal_type(A() == A())  # revealed: bool
-reveal_type(A() != A())  # revealed: bool
+# TODO: it should be `bool`, need to check arg type and fall back to `is` and `is not`
+reveal_type(A() == A())  # revealed: A
+reveal_type(A() != A())  # revealed: A
 ```
 
 ## Object Comparisons with Typeshed
@@ -330,14 +305,12 @@ reveal_type(1 >= 1.0)  # revealed: bool
 reveal_type(1 == 2j)  # revealed: bool
 reveal_type(1 != 2j)  # revealed: bool
 
-# error: [unsupported-operator] "Operator `<` is not supported for types `int` and `complex`, in comparing `Literal[1]` with `complex`"
-reveal_type(1 < 2j)  # revealed: Unknown
-# error: [unsupported-operator] "Operator `<=` is not supported for types `int` and `complex`, in comparing `Literal[1]` with `complex`"
-reveal_type(1 <= 2j)  # revealed: Unknown
-# error: [unsupported-operator] "Operator `>` is not supported for types `int` and `complex`, in comparing `Literal[1]` with `complex`"
-reveal_type(1 > 2j)  # revealed: Unknown
-# error: [unsupported-operator] "Operator `>=` is not supported for types `int` and `complex`, in comparing `Literal[1]` with `complex`"
-reveal_type(1 >= 2j)  # revealed: Unknown
+# TODO: should be Unknown and emit diagnostic,
+# need to check arg type and should be failed
+reveal_type(1 < 2j)  # revealed: bool
+reveal_type(1 <= 2j)  # revealed: bool
+reveal_type(1 > 2j)  # revealed: bool
+reveal_type(1 >= 2j)  # revealed: bool
 
 def f(x: bool, y: int):
     reveal_type(x < y)  # revealed: bool
@@ -345,47 +318,3 @@ def f(x: bool, y: int):
     reveal_type(4.2 < x)  # revealed: bool
     reveal_type(x < 4.2)  # revealed: bool
 ```
-
-## Chained comparisons with objects that don't implement `__bool__` correctly
-
-<!-- snapshot-diagnostics -->
-
-Python implicitly calls `bool` on the comparison result of preceding elements (but not for the last
-element) of a chained comparison.
-
-```py
-class NotBoolable:
-    __bool__ = 3
-
-class Comparable:
-    def __lt__(self, item) -> NotBoolable:
-        return NotBoolable()
-
-    def __gt__(self, item) -> NotBoolable:
-        return NotBoolable()
-
-# error: [unsupported-bool-conversion]
-10 < Comparable() < 20
-# error: [unsupported-bool-conversion]
-10 < Comparable() < Comparable()
-
-Comparable() < Comparable()  # fine
-```
-
-## Callables as comparison dunders
-
-```py
-from typing import Literal
-
-class AlwaysTrue:
-    def __call__(self, other: object) -> Literal[True]:
-        return True
-
-class A:
-    __eq__: AlwaysTrue = AlwaysTrue()
-    __lt__: AlwaysTrue = AlwaysTrue()
-
-reveal_type(A() == A())  # revealed: Literal[True]
-reveal_type(A() < A())  # revealed: Literal[True]
-reveal_type(A() > A())  # revealed: Literal[True]
-```

crates/red_knot_python_semantic/resources/mdtest/comparison/integers.md

@@ -12,8 +12,8 @@ reveal_type(1 is 1)  # revealed: bool
 reveal_type(1 is not 1)  # revealed: bool
 reveal_type(1 is 2)  # revealed: Literal[False]
 reveal_type(1 is not 7)  # revealed: Literal[True]
-# error: [unsupported-operator] "Operator `<=` is not supported for types `int` and `str`, in comparing `Literal[1]` with `Literal[""]`"
-reveal_type(1 <= "" and 0 < 1)  # revealed: Unknown & ~AlwaysTruthy | Literal[True]
+# TODO: should be Unknown, and emit diagnostic, once we check call argument types
+reveal_type(1 <= "" and 0 < 1)  # revealed: bool
 ```
 
 ## Integer instance

crates/red_knot_python_semantic/resources/mdtest/comparison/intersections.md

@@ -6,11 +6,7 @@ If we have an intersection type `A & B` and we get a definitive true/false answe
 types, we can infer that the result for the intersection type is also true/false:
 
 ```py
-from typing import Literal
-
-class Base:
-    def __gt__(self, other) -> bool:
-        return False
+class Base: ...
 
 class Child1(Base):
     def __eq__(self, other) -> Literal[True]:

crates/red_knot_python_semantic/resources/mdtest/comparison/non_bool_returns.md

@@ -23,7 +23,6 @@ from __future__ import annotations
 
 class A:
     def __lt__(self, other) -> A: ...
-    def __gt__(self, other) -> bool: ...
 
 class B:
     def __lt__(self, other) -> B: ...

crates/red_knot_python_semantic/resources/mdtest/comparison/tuples.md

@@ -33,7 +33,7 @@ reveal_type(a >= b)  # revealed: Literal[False]
 
 Even when tuples have different lengths, comparisons should be handled appropriately.
 
-```py
+```py path=different_length.py
 a = (1, 2, 3)
 b = (1, 2, 3, 4)
 
@@ -58,7 +58,22 @@ reveal_type(c >= d)  # revealed: Literal[True]
 #### Results with Ambiguity
 
 ```py
-def _(x: bool, y: int):
+class P:
+    def __lt__(self, other: "P") -> bool:
+        return True
+
+    def __le__(self, other: "P") -> bool:
+        return True
+
+    def __gt__(self, other: "P") -> bool:
+        return True
+
+    def __ge__(self, other: "P") -> bool:
+        return True
+
+class Q(P): ...
+
+def _(x: P, y: Q):
     a = (x,)
     b = (y,)
 
@@ -92,20 +107,17 @@ reveal_type(a == b)  # revealed: bool
 # TODO: should be Literal[True], once we implement (in)equality for mismatched literals
 reveal_type(a != b)  # revealed: bool
 
-# error: [unsupported-operator] "Operator `<` is not supported for types `int` and `str`, in comparing `tuple[Literal[1], Literal[2]]` with `tuple[Literal[1], Literal["hello"]]`"
-reveal_type(a < b)  # revealed: Unknown
-# error: [unsupported-operator] "Operator `<=` is not supported for types `int` and `str`, in comparing `tuple[Literal[1], Literal[2]]` with `tuple[Literal[1], Literal["hello"]]`"
-reveal_type(a <= b)  # revealed: Unknown
-# error: [unsupported-operator] "Operator `>` is not supported for types `int` and `str`, in comparing `tuple[Literal[1], Literal[2]]` with `tuple[Literal[1], Literal["hello"]]`"
-reveal_type(a > b)  # revealed: Unknown
-# error: [unsupported-operator] "Operator `>=` is not supported for types `int` and `str`, in comparing `tuple[Literal[1], Literal[2]]` with `tuple[Literal[1], Literal["hello"]]`"
-reveal_type(a >= b)  # revealed: Unknown
+# TODO: should be Unknown and add more informative diagnostics
+reveal_type(a < b)  # revealed: bool
+reveal_type(a <= b)  # revealed: bool
+reveal_type(a > b)  # revealed: bool
+reveal_type(a >= b)  # revealed: bool
 ```
 
 However, if the lexicographic comparison completes without reaching a point where str and int are
 compared, Python will still produce a result based on the prior elements.
 
-```py
+```py path=short_circuit.py
 a = (1, 2)
 b = (999999, "hello")
 
@@ -147,40 +159,33 @@ of the dunder methods.)
 ```py
 from __future__ import annotations
 
-class EqReturnType: ...
-class NeReturnType: ...
-class LtReturnType: ...
-class LeReturnType: ...
-class GtReturnType: ...
-class GeReturnType: ...
-
 class A:
-    def __eq__(self, o: object) -> EqReturnType:
-        return EqReturnType()
+    def __eq__(self, o: object) -> str:
+        return "hello"
 
-    def __ne__(self, o: object) -> NeReturnType:
-        return NeReturnType()
+    def __ne__(self, o: object) -> bytes:
+        return b"world"
 
-    def __lt__(self, o: A) -> LtReturnType:
-        return LtReturnType()
+    def __lt__(self, o: A) -> float:
+        return 3.14
 
-    def __le__(self, o: A) -> LeReturnType:
-        return LeReturnType()
+    def __le__(self, o: A) -> complex:
+        return complex(0.5, -0.5)
 
-    def __gt__(self, o: A) -> GtReturnType:
-        return GtReturnType()
+    def __gt__(self, o: A) -> tuple:
+        return (1, 2, 3)
 
-    def __ge__(self, o: A) -> GeReturnType:
-        return GeReturnType()
+    def __ge__(self, o: A) -> list:
+        return [1, 2, 3]
 
 a = (A(), A())
 
 reveal_type(a == a)  # revealed: bool
 reveal_type(a != a)  # revealed: bool
-reveal_type(a < a)  # revealed: LtReturnType | Literal[False]
-reveal_type(a <= a)  # revealed: LeReturnType | Literal[True]
-reveal_type(a > a)  # revealed: GtReturnType | Literal[False]
-reveal_type(a >= a)  # revealed: GeReturnType | Literal[True]
+reveal_type(a < a)  # revealed: float | Literal[False]
+reveal_type(a <= a)  # revealed: complex | Literal[True]
+reveal_type(a > a)  # revealed: tuple | Literal[False]
+reveal_type(a >= a)  # revealed: list | Literal[True]
 
 # If lexicographic comparison is finished before comparing A()
 b = ("1_foo", A())
@@ -193,13 +198,11 @@ reveal_type(b <= c)  # revealed: Literal[True]
 reveal_type(b > c)  # revealed: Literal[False]
 reveal_type(b >= c)  # revealed: Literal[False]
 
-class LtReturnTypeOnB: ...
-
 class B:
-    def __lt__(self, o: B) -> LtReturnTypeOnB:
+    def __lt__(self, o: B) -> set:
         return set()
 
-reveal_type((A(), B()) < (A(), B()))  # revealed: LtReturnType | LtReturnTypeOnB | Literal[False]
+reveal_type((A(), B()) < (A(), B()))  # revealed: float | set | Literal[False]
 ```
 
 #### Special Handling of Eq and NotEq in Lexicographic Comparisons
@@ -334,61 +337,3 @@ reveal_type(a is not c)  # revealed: Literal[True]
 For tuples like `tuple[int, ...]`, `tuple[Any, ...]`
 
 // TODO
-
-## Chained comparisons with elements that incorrectly implement `__bool__`
-
-<!-- snapshot-diagnostics -->
-
-For an operation `A() < A()` to succeed at runtime, the `A.__lt__` method does not necessarily need
-to return an object that is convertible to a `bool`. However, the return type _does_ need to be
-convertible to a `bool` for the operation `A() < A() < A()` (a _chained_ comparison) to succeed.
-This is because `A() < A() < A()` desugars to something like this, which involves several implicit
-conversions to `bool`:
-
-```ignore
-def compute_chained_comparison():
-  a1 = A()
-  a2 = A()
-  first_comparison = a1 < a2
-  return first_comparison and (a2 < A())
-```
-
-```py
-class NotBoolable:
-    __bool__ = 5
-
-class Comparable:
-    def __lt__(self, other) -> NotBoolable:
-        return NotBoolable()
-
-    def __gt__(self, other) -> NotBoolable:
-        return NotBoolable()
-
-a = (1, Comparable())
-b = (1, Comparable())
-
-# error: [unsupported-bool-conversion]
-a < b < b
-
-a < b  # fine
-```
-
-## Equality with elements that incorrectly implement `__bool__`
-
-<!-- snapshot-diagnostics -->
-
-Python does not generally attempt to coerce the result of `==` and `!=` operations between two
-arbitrary objects to a `bool`, but a comparison of tuples will fail if the result of comparing any
-pair of elements at equivalent positions cannot be converted to a `bool`:
-
-```py
-class A:
-    def __eq__(self, other) -> NotBoolable:
-        return NotBoolable()
-
-class NotBoolable:
-    __bool__ = None
-
-# error: [unsupported-bool-conversion]
-(A(),) == (A(),)
-```

crates/red_knot_python_semantic/resources/mdtest/comparison/unsupported.md

@@ -9,22 +9,28 @@ def _(flag: bool, flag1: bool, flag2: bool):
     b = 0 not in 10  # error: "Operator `not in` is not supported for types `Literal[0]` and `Literal[10]`"
     reveal_type(b)  # revealed: bool
 
-    # error: [unsupported-operator] "Operator `<` is not supported for types `object` and `int`, in comparing `object` with `Literal[5]`"
+    # TODO: should error, once operand type check is implemented
+    # ("Operator `<` is not supported for types `object` and `int`")
     c = object() < 5
-    reveal_type(c)  # revealed: Unknown
+    # TODO: should be Unknown, once operand type check is implemented
+    reveal_type(c)  # revealed: bool
 
-    # error: [unsupported-operator] "Operator `<` is not supported for types `int` and `object`, in comparing `Literal[5]` with `object`"
+    # TODO: should error, once operand type check is implemented
+    # ("Operator `<` is not supported for types `int` and `object`")
     d = 5 < object()
-    reveal_type(d)  # revealed: Unknown
+    # TODO: should be Unknown, once operand type check is implemented
+    reveal_type(d)  # revealed: bool
 
     int_literal_or_str_literal = 1 if flag else "foo"
     # error: "Operator `in` is not supported for types `Literal[42]` and `Literal[1]`, in comparing `Literal[42]` with `Literal[1, "foo"]`"
     e = 42 in int_literal_or_str_literal
     reveal_type(e)  # revealed: bool
 
-    # error: [unsupported-operator] "Operator `<` is not supported for types `int` and `str`, in comparing `tuple[Literal[1], Literal[2]]` with `tuple[Literal[1], Literal["hello"]]`"
+    # TODO: should error, need to check if __lt__ signature is valid for right operand
+    # error may be "Operator `<` is not supported for types `int` and `str`, in comparing `tuple[Literal[1], Literal[2]]` with `tuple[Literal[1], Literal["hello"]]`
     f = (1, 2) < (1, "hello")
-    reveal_type(f)  # revealed: Unknown
+    # TODO: should be Unknown, once operand type check is implemented
+    reveal_type(f)  # revealed: bool
 
     # error: [unsupported-operator] "Operator `<` is not supported for types `A` and `A`, in comparing `tuple[bool, A]` with `tuple[bool, A]`"
     g = (flag1, A()) < (flag2, A())

crates/red_knot_python_semantic/resources/mdtest/comprehensions/basic.md

@@ -43,7 +43,8 @@ class IntIterable:
     def __iter__(self) -> IntIterator:
         return IntIterator()
 
-# revealed: tuple[int, int]
+# TODO: This could be a `tuple[int, int]` if we model that `y` can not be modified in the outer comprehension scope
+# revealed: tuple[int, Unknown | int]
 [[reveal_type((x, y)) for x in IntIterable()] for y in IntIterable()]
 ```
 
@@ -66,7 +67,8 @@ class IterableOfIterables:
     def __iter__(self) -> IteratorOfIterables:
         return IteratorOfIterables()
 
-# revealed: tuple[int, IntIterable]
+# TODO: This could be a `tuple[int, int]` (see above)
+# revealed: tuple[int, Unknown | IntIterable]
 [[reveal_type((x, y)) for x in y] for y in IterableOfIterables()]
 ```
 

crates/red_knot_python_semantic/resources/mdtest/conditional/if_expression.md

@@ -35,13 +35,3 @@ def _(flag: bool):
     x = 1 if flag else None
     reveal_type(x)  # revealed: Literal[1] | None
 ```
-
-## Condition with object that implements `__bool__` incorrectly
-
-```py
-class NotBoolable:
-    __bool__ = 3
-
-# error: [unsupported-bool-conversion] "Boolean conversion is unsupported for type `NotBoolable`; its `__bool__` method isn't callable"
-3 if NotBoolable() else 4
-```

crates/red_knot_python_semantic/resources/mdtest/conditional/if_statement.md

@@ -147,17 +147,3 @@ def _(flag: bool):
 
     reveal_type(y)  # revealed: Literal[0, 1]
 ```
-
-## Condition with object that implements `__bool__` incorrectly
-
-```py
-class NotBoolable:
-    __bool__ = 3
-
-# error: [unsupported-bool-conversion] "Boolean conversion is unsupported for type `NotBoolable`; its `__bool__` method isn't callable"
-if NotBoolable():
-    ...
-# error: [unsupported-bool-conversion] "Boolean conversion is unsupported for type `NotBoolable`; its `__bool__` method isn't callable"
-elif NotBoolable():
-    ...
-```

crates/red_knot_python_semantic/resources/mdtest/conditional/match.md

@@ -43,21 +43,3 @@ def _(target: int):
 
     reveal_type(y)  # revealed: Literal[2, 3, 4]
 ```
-
-## Guard with object that implements `__bool__` incorrectly
-
-```py
-class NotBoolable:
-    __bool__ = 3
-
-def _(target: int, flag: NotBoolable):
-    y = 1
-    match target:
-        # error: [unsupported-bool-conversion] "Boolean conversion is unsupported for type `NotBoolable`; its `__bool__` method isn't callable"
-        case 1 if flag:
-            y = 2
-        case 2:
-            y = 3
-
-    reveal_type(y)  # revealed: Literal[1, 2, 3]
-```

crates/red_knot_python_semantic/resources/mdtest/descriptor_protocol.md

@@ -1,742 +0,0 @@
-# Descriptor protocol
-
-[Descriptors] let objects customize attribute lookup, storage, and deletion.
-
-A descriptor is an attribute value that has one of the methods in the descriptor protocol. Those
-methods are `__get__()`, `__set__()`, and `__delete__()`. If any of those methods are defined for an
-attribute, it is said to be a descriptor.
-
-## Basic example
-
-An introductory example, modeled after a [simple example] in the primer on descriptors, involving a
-descriptor that returns a constant value:
-
-```py
-from typing import Literal
-
-class Ten:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal[10]:
-        return 10
-
-    def __set__(self, instance: object, value: Literal[10]) -> None:
-        pass
-
-class C:
-    ten: Ten = Ten()
-
-c = C()
-
-reveal_type(c.ten)  # revealed: Literal[10]
-
-reveal_type(C.ten)  # revealed: Literal[10]
-
-# These are fine:
-c.ten = 10
-C.ten = 10
-
-# error: [invalid-assignment] "Object of type `Literal[11]` is not assignable to attribute `ten` of type `Literal[10]`"
-c.ten = 11
-
-# error: [invalid-assignment] "Object of type `Literal[11]` is not assignable to attribute `ten` of type `Literal[10]`"
-C.ten = 11
-```
-
-## Different types for `__get__` and `__set__`
-
-The return type of `__get__` and the value type of `__set__` can be different:
-
-```py
-class FlexibleInt:
-    def __init__(self):
-        self._value: int | None = None
-
-    def __get__(self, instance: object, owner: type | None = None) -> int | None:
-        return self._value
-
-    def __set__(self, instance: object, value: int | str) -> None:
-        self._value = int(value)
-
-class C:
-    flexible_int: FlexibleInt = FlexibleInt()
-
-c = C()
-
-reveal_type(c.flexible_int)  # revealed: int | None
-
-c.flexible_int = 42  # okay
-# TODO: This should not be an error
-# error: [invalid-assignment]
-c.flexible_int = "42"  # also okay!
-
-reveal_type(c.flexible_int)  # revealed: int | None
-
-# TODO: This should be an error
-c.flexible_int = None  # not okay
-
-reveal_type(c.flexible_int)  # revealed: int | None
-```
-
-## Data and non-data descriptors
-
-Descriptors that define `__set__` or `__delete__` are called *data descriptors*. An example of a
-data descriptor is a `property` with a setter and/or a deleter. Descriptors that only define
-`__get__`, meanwhile, are called *non-data descriptors*. Examples include functions, `classmethod`
-or `staticmethod`.
-
-The precedence chain for attribute access is (1) data descriptors, (2) instance attributes, and (3)
-non-data descriptors.
-
-```py
-from typing import Literal
-
-class DataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["data"]:
-        return "data"
-
-    def __set__(self, instance: object, value: int) -> None:
-        pass
-
-class NonDataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["non-data"]:
-        return "non-data"
-
-class C:
-    data_descriptor = DataDescriptor()
-    non_data_descriptor = NonDataDescriptor()
-
-    def f(self):
-        # This explains why data descriptors come first in the precedence chain. If
-        # instance attributes would take priority, we would override the descriptor
-        # here. Instead, this calls `DataDescriptor.__set__`, i.e. it does not affect
-        # the type of the `data_descriptor` attribute.
-        self.data_descriptor = 1
-
-        # However, for non-data descriptors, instance attributes do take precedence.
-        # So it is possible to override them.
-        self.non_data_descriptor = 1
-
-c = C()
-
-reveal_type(c.data_descriptor)  # revealed: Unknown | Literal["data"]
-
-reveal_type(c.non_data_descriptor)  # revealed: Unknown | Literal["non-data", 1]
-
-reveal_type(C.data_descriptor)  # revealed: Unknown | Literal["data"]
-
-reveal_type(C.non_data_descriptor)  # revealed: Unknown | Literal["non-data"]
-
-# It is possible to override data descriptors via class objects. The following
-# assignment does not call `DataDescriptor.__set__`. For this reason, we infer
-# `Unknown | …` for all (descriptor) attributes.
-C.data_descriptor = "something else"  # This is okay
-```
-
-## Descriptor protocol for class objects
-
-When attributes are accessed on a class object, the following [precedence chain] is used:
-
-- Data descriptor on the metaclass
-- Data or non-data descriptor on the class
-- Class attribute
-- Non-data descriptor on the metaclass
-- Metaclass attribute
-
-To verify this, we define a data and a non-data descriptor:
-
-```py
-from typing import Literal, Any
-
-class DataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["data"]:
-        return "data"
-
-    def __set__(self, instance: object, value: str) -> None:
-        pass
-
-class NonDataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["non-data"]:
-        return "non-data"
-```
-
-First, we make sure that the descriptors are correctly accessed when defined on the metaclass or the
-class:
-
-```py
-class Meta1(type):
-    meta_data_descriptor: DataDescriptor = DataDescriptor()
-    meta_non_data_descriptor: NonDataDescriptor = NonDataDescriptor()
-
-class C1(metaclass=Meta1):
-    class_data_descriptor: DataDescriptor = DataDescriptor()
-    class_non_data_descriptor: NonDataDescriptor = NonDataDescriptor()
-
-reveal_type(C1.meta_data_descriptor)  # revealed: Literal["data"]
-reveal_type(C1.meta_non_data_descriptor)  # revealed: Literal["non-data"]
-
-reveal_type(C1.class_data_descriptor)  # revealed: Literal["data"]
-reveal_type(C1.class_non_data_descriptor)  # revealed: Literal["non-data"]
-```
-
-Next, we demonstrate that a *metaclass data descriptor* takes precedence over all class-level
-attributes:
-
-```py
-class Meta2(type):
-    meta_data_descriptor1: DataDescriptor = DataDescriptor()
-    meta_data_descriptor2: DataDescriptor = DataDescriptor()
-
-class ClassLevelDataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["class level data descriptor"]:
-        return "class level data descriptor"
-
-    def __set__(self, instance: object, value: str) -> None:
-        pass
-
-class C2(metaclass=Meta2):
-    meta_data_descriptor1: Literal["value on class"] = "value on class"
-    meta_data_descriptor2: ClassLevelDataDescriptor = ClassLevelDataDescriptor()
-
-reveal_type(C2.meta_data_descriptor1)  # revealed: Literal["data"]
-reveal_type(C2.meta_data_descriptor2)  # revealed: Literal["data"]
-```
-
-On the other hand, normal metaclass attributes and metaclass non-data descriptors are shadowed by
-class-level attributes (descriptor or not):
-
-```py
-class Meta3(type):
-    meta_attribute1: Literal["value on metaclass"] = "value on metaclass"
-    meta_attribute2: Literal["value on metaclass"] = "value on metaclass"
-    meta_non_data_descriptor1: NonDataDescriptor = NonDataDescriptor()
-    meta_non_data_descriptor2: NonDataDescriptor = NonDataDescriptor()
-
-class C3(metaclass=Meta3):
-    meta_attribute1: Literal["value on class"] = "value on class"
-    meta_attribute2: ClassLevelDataDescriptor = ClassLevelDataDescriptor()
-    meta_non_data_descriptor1: Literal["value on class"] = "value on class"
-    meta_non_data_descriptor2: ClassLevelDataDescriptor = ClassLevelDataDescriptor()
-
-reveal_type(C3.meta_attribute1)  # revealed: Literal["value on class"]
-reveal_type(C3.meta_attribute2)  # revealed: Literal["class level data descriptor"]
-reveal_type(C3.meta_non_data_descriptor1)  # revealed: Literal["value on class"]
-reveal_type(C3.meta_non_data_descriptor2)  # revealed: Literal["class level data descriptor"]
-```
-
-Finally, metaclass attributes and metaclass non-data descriptors are only accessible when they are
-not shadowed by class-level attributes:
-
-```py
-class Meta4(type):
-    meta_attribute: Literal["value on metaclass"] = "value on metaclass"
-    meta_non_data_descriptor: NonDataDescriptor = NonDataDescriptor()
-
-class C4(metaclass=Meta4): ...
-
-reveal_type(C4.meta_attribute)  # revealed: Literal["value on metaclass"]
-reveal_type(C4.meta_non_data_descriptor)  # revealed: Literal["non-data"]
-```
-
-When a metaclass data descriptor is possibly unbound, we union the result type of its `__get__`
-method with an underlying class level attribute, if present:
-
-```py
-def _(flag: bool):
-    class Meta5(type):
-        if flag:
-            meta_data_descriptor1: DataDescriptor = DataDescriptor()
-            meta_data_descriptor2: DataDescriptor = DataDescriptor()
-
-    class C5(metaclass=Meta5):
-        meta_data_descriptor1: Literal["value on class"] = "value on class"
-
-    reveal_type(C5.meta_data_descriptor1)  # revealed: Literal["data", "value on class"]
-    # error: [possibly-unbound-attribute]
-    reveal_type(C5.meta_data_descriptor2)  # revealed: Literal["data"]
-```
-
-When a class-level attribute is possibly unbound, we union its (descriptor protocol) type with the
-metaclass attribute (unless it's a data descriptor, which always takes precedence):
-
-```py
-from typing import Any
-
-def _(flag: bool):
-    class Meta6(type):
-        attribute1: DataDescriptor = DataDescriptor()
-        attribute2: NonDataDescriptor = NonDataDescriptor()
-        attribute3: Literal["value on metaclass"] = "value on metaclass"
-
-    class C6(metaclass=Meta6):
-        if flag:
-            attribute1: Literal["value on class"] = "value on class"
-            attribute2: Literal["value on class"] = "value on class"
-            attribute3: Literal["value on class"] = "value on class"
-            attribute4: Literal["value on class"] = "value on class"
-
-    reveal_type(C6.attribute1)  # revealed: Literal["data"]
-    reveal_type(C6.attribute2)  # revealed: Literal["non-data", "value on class"]
-    reveal_type(C6.attribute3)  # revealed: Literal["value on metaclass", "value on class"]
-    # error: [possibly-unbound-attribute]
-    reveal_type(C6.attribute4)  # revealed: Literal["value on class"]
-```
-
-Finally, we can also have unions of various types of attributes:
-
-```py
-def _(flag: bool):
-    class Meta7(type):
-        if flag:
-            union_of_metaclass_attributes: Literal[1] = 1
-            union_of_metaclass_data_descriptor_and_attribute: DataDescriptor = DataDescriptor()
-        else:
-            union_of_metaclass_attributes: Literal[2] = 2
-            union_of_metaclass_data_descriptor_and_attribute: Literal[2] = 2
-
-    class C7(metaclass=Meta7):
-        if flag:
-            union_of_class_attributes: Literal[1] = 1
-            union_of_class_data_descriptor_and_attribute: DataDescriptor = DataDescriptor()
-        else:
-            union_of_class_attributes: Literal[2] = 2
-            union_of_class_data_descriptor_and_attribute: Literal[2] = 2
-
-    reveal_type(C7.union_of_metaclass_attributes)  # revealed: Literal[1, 2]
-    reveal_type(C7.union_of_metaclass_data_descriptor_and_attribute)  # revealed: Literal["data", 2]
-    reveal_type(C7.union_of_class_attributes)  # revealed: Literal[1, 2]
-    reveal_type(C7.union_of_class_data_descriptor_and_attribute)  # revealed: Literal["data", 2]
-```
-
-## Partial fall back
-
-Our implementation of the descriptor protocol takes into account that symbols can be possibly
-unbound. In those cases, we fall back to lower precedence steps of the descriptor protocol and union
-all possible results accordingly. We start by defining a data and a non-data descriptor:
-
-```py
-from typing import Literal
-
-class DataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["data"]:
-        return "data"
-
-    def __set__(self, instance: object, value: int) -> None:
-        pass
-
-class NonDataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal["non-data"]:
-        return "non-data"
-```
-
-Then, we demonstrate that we fall back to an instance attribute if a data descriptor is possibly
-unbound:
-
-```py
-def f1(flag: bool):
-    class C1:
-        if flag:
-            attr = DataDescriptor()
-
-        def f(self):
-            self.attr = "normal"
-
-    reveal_type(C1().attr)  # revealed: Unknown | Literal["data", "normal"]
-```
-
-We never treat implicit instance attributes as definitely bound, so we fall back to the non-data
-descriptor here:
-
-```py
-def f2(flag: bool):
-    class C2:
-        def f(self):
-            self.attr = "normal"
-        attr = NonDataDescriptor()
-
-    reveal_type(C2().attr)  # revealed: Unknown | Literal["non-data", "normal"]
-```
-
-## Built-in `property` descriptor
-
-The built-in `property` decorator creates a descriptor. The names for attribute reads/writes are
-determined by the return type of the `name` method and the parameter type of the setter,
-respectively.
-
-```py
-class C:
-    _name: str | None = None
-
-    @property
-    def name(self) -> str:
-        return self._name or "Unset"
-    # TODO: No diagnostic should be emitted here
-    # error: [unresolved-attribute] "Type `Literal[name]` has no attribute `setter`"
-    @name.setter
-    def name(self, value: str | None) -> None:
-        self._value = value
-
-c = C()
-
-reveal_type(c._name)  # revealed: str | None
-
-# TODO: Should be `str`
-reveal_type(c.name)  # revealed: <bound method `name` of `C`>
-
-# Should be `builtins.property`
-reveal_type(C.name)  # revealed: Literal[name]
-
-# TODO: These should not emit errors
-# error: [invalid-assignment]
-c.name = "new"
-
-# error: [invalid-assignment]
-c.name = None
-
-# TODO: this should be an error, but with a proper error message
-# error: [invalid-assignment] "Object of type `Literal[42]` is not assignable to attribute `name` of type `<bound method `name` of `C`>`"
-c.name = 42
-```
-
-## Built-in `classmethod` descriptor
-
-Similarly to `property`, `classmethod` decorator creates an implicit descriptor that binds the first
-argument to the class instead of the instance.
-
-```py
-class C:
-    def __init__(self, value: str) -> None:
-        self._name: str = value
-
-    @classmethod
-    def factory(cls, value: str) -> "C":
-        return cls(value)
-
-    @classmethod
-    def get_name(cls) -> str:
-        return cls.__name__
-
-c1 = C.factory("test")  # okay
-
-reveal_type(c1)  # revealed: C
-
-reveal_type(C.get_name())  # revealed: str
-
-reveal_type(C("42").get_name())  # revealed: str
-```
-
-## Descriptors only work when used as class variables
-
-From the descriptor guide:
-
-> Descriptors only work when used as class variables. When put in instances, they have no effect.
-
-```py
-from typing import Literal
-
-class Ten:
-    def __get__(self, instance: object, owner: type | None = None) -> Literal[10]:
-        return 10
-
-class C:
-    def __init__(self):
-        self.ten: Ten = Ten()
-
-reveal_type(C().ten)  # revealed: Ten
-```
-
-## Descriptors distinguishing between class and instance access
-
-Overloads can be used to distinguish between when a descriptor is accessed on a class object and
-when it is accessed on an instance. A real-world example of this is the `__get__` method on
-`types.FunctionType`.
-
-```py
-from typing_extensions import Literal, LiteralString, overload
-
-class Descriptor:
-    @overload
-    def __get__(self, instance: None, owner: type, /) -> Literal["called on class object"]: ...
-    @overload
-    def __get__(self, instance: object, owner: type | None = None, /) -> Literal["called on instance"]: ...
-    def __get__(self, instance, owner=None, /) -> LiteralString:
-        if instance:
-            return "called on instance"
-        else:
-            return "called on class object"
-
-class C:
-    d: Descriptor = Descriptor()
-
-# TODO: should be `Literal["called on class object"]
-reveal_type(C.d)  # revealed: LiteralString
-
-# TODO: should be `Literal["called on instance"]
-reveal_type(C().d)  # revealed: LiteralString
-```
-
-## Undeclared descriptor arguments
-
-If a descriptor attribute is not declared, we union with `Unknown`, just like for regular
-attributes, since that attribute could be overwritten externally. Even a data descriptor with a
-`__set__` method can be overwritten when accessed through a class object.
-
-```py
-class Descriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> int:
-        return 1
-
-    def __set__(self, instance: object, value: int) -> None:
-        pass
-
-class C:
-    descriptor = Descriptor()
-
-C.descriptor = "something else"
-
-# This could also be `Literal["something else"]` if we support narrowing of attribute types based on assignments
-reveal_type(C.descriptor)  # revealed: Unknown | int
-```
-
-## `__get__` is called with correct arguments
-
-```py
-from __future__ import annotations
-
-class TailoredForClassObjectAccess:
-    def __get__(self, instance: None, owner: type[C]) -> int:
-        return 1
-
-class TailoredForInstanceAccess:
-    def __get__(self, instance: C, owner: type[C] | None = None) -> str:
-        return "a"
-
-class TailoredForMetaclassAccess:
-    def __get__(self, instance: type[C], owner: type[Meta]) -> bytes:
-        return b"a"
-
-class Meta(type):
-    metaclass_access: TailoredForMetaclassAccess = TailoredForMetaclassAccess()
-
-class C(metaclass=Meta):
-    class_object_access: TailoredForClassObjectAccess = TailoredForClassObjectAccess()
-    instance_access: TailoredForInstanceAccess = TailoredForInstanceAccess()
-
-reveal_type(C.class_object_access)  # revealed: int
-reveal_type(C().instance_access)  # revealed: str
-reveal_type(C.metaclass_access)  # revealed: bytes
-
-# TODO: These should emit a diagnostic
-reveal_type(C().class_object_access)  # revealed: TailoredForClassObjectAccess
-reveal_type(C.instance_access)  # revealed: TailoredForInstanceAccess
-```
-
-## Descriptors with incorrect `__get__` signature
-
-```py
-class Descriptor:
-    # `__get__` method with missing parameters:
-    def __get__(self) -> int:
-        return 1
-
-class C:
-    descriptor: Descriptor = Descriptor()
-
-# TODO: This should be an error
-reveal_type(C.descriptor)  # revealed: Descriptor
-
-# TODO: This should be an error
-reveal_type(C().descriptor)  # revealed: Descriptor
-```
-
-## Possibly unbound descriptor attributes
-
-```py
-class DataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> int:
-        return 1
-
-    def __set__(self, instance: int, value) -> None:
-        pass
-
-class NonDataDescriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> int:
-        return 1
-
-def _(flag: bool):
-    class PossiblyUnbound:
-        if flag:
-            non_data: NonDataDescriptor = NonDataDescriptor()
-            data: DataDescriptor = DataDescriptor()
-
-    # error: [possibly-unbound-attribute] "Attribute `non_data` on type `Literal[PossiblyUnbound]` is possibly unbound"
-    reveal_type(PossiblyUnbound.non_data)  # revealed: int
-
-    # error: [possibly-unbound-attribute] "Attribute `non_data` on type `PossiblyUnbound` is possibly unbound"
-    reveal_type(PossiblyUnbound().non_data)  # revealed: int
-
-    # error: [possibly-unbound-attribute] "Attribute `data` on type `Literal[PossiblyUnbound]` is possibly unbound"
-    reveal_type(PossiblyUnbound.data)  # revealed: int
-
-    # error: [possibly-unbound-attribute] "Attribute `data` on type `PossiblyUnbound` is possibly unbound"
-    reveal_type(PossiblyUnbound().data)  # revealed: int
-```
-
-## Possibly-unbound `__get__` method
-
-```py
-def _(flag: bool):
-    class MaybeDescriptor:
-        if flag:
-            def __get__(self, instance: object, owner: type | None = None) -> int:
-                return 1
-
-    class C:
-        descriptor: MaybeDescriptor = MaybeDescriptor()
-
-    reveal_type(C.descriptor)  # revealed: int | MaybeDescriptor
-
-    reveal_type(C().descriptor)  # revealed: int | MaybeDescriptor
-```
-
-## Descriptors with non-function `__get__` callables that are descriptors themselves
-
-The descriptor protocol is recursive, i.e. looking up `__get__` can involve triggering the
-descriptor protocol on the callable's `__call__` method:
-
-```py
-from __future__ import annotations
-
-class ReturnedCallable2:
-    def __call__(self, descriptor: Descriptor1, instance: None, owner: type[C]) -> int:
-        return 1
-
-class ReturnedCallable1:
-    def __call__(self, descriptor: Descriptor2, instance: Callable1, owner: type[Callable1]) -> ReturnedCallable2:
-        return ReturnedCallable2()
-
-class Callable3:
-    def __call__(self, descriptor: Descriptor3, instance: Callable2, owner: type[Callable2]) -> ReturnedCallable1:
-        return ReturnedCallable1()
-
-class Descriptor3:
-    __get__: Callable3 = Callable3()
-
-class Callable2:
-    __call__: Descriptor3 = Descriptor3()
-
-class Descriptor2:
-    __get__: Callable2 = Callable2()
-
-class Callable1:
-    __call__: Descriptor2 = Descriptor2()
-
-class Descriptor1:
-    __get__: Callable1 = Callable1()
-
-class C:
-    d: Descriptor1 = Descriptor1()
-
-reveal_type(C.d)  # revealed: int
-```
-
-## Dunder methods
-
-Dunder methods are looked up on the meta-type, but we still need to invoke the descriptor protocol:
-
-```py
-class SomeCallable:
-    def __call__(self, x: int) -> str:
-        return "a"
-
-class Descriptor:
-    def __get__(self, instance: object, owner: type | None = None) -> SomeCallable:
-        return SomeCallable()
-
-class B:
-    __call__: Descriptor = Descriptor()
-
-b_instance = B()
-reveal_type(b_instance(1))  # revealed: str
-
-b_instance("bla")  # error: [invalid-argument-type]
-```
-
-## Functions as descriptors
-
-Functions are descriptors because they implement a `__get__` method. This is crucial in making sure
-that method calls work as expected. See [this test suite](./call/methods.md) for more information.
-Here, we only demonstrate how `__get__` works on functions:
-
-```py
-from inspect import getattr_static
-
-def f(x: object) -> str:
-    return "a"
-
-reveal_type(f)  # revealed: Literal[f]
-reveal_type(f.__get__)  # revealed: <method-wrapper `__get__` of `f`>
-reveal_type(f.__get__(None, type(f)))  # revealed: Literal[f]
-reveal_type(f.__get__(None, type(f))(1))  # revealed: str
-
-wrapper_descriptor = getattr_static(f, "__get__")
-
-reveal_type(wrapper_descriptor)  # revealed: <wrapper-descriptor `__get__` of `function` objects>
-reveal_type(wrapper_descriptor(f, None, type(f)))  # revealed: Literal[f]
-
-# Attribute access on the method-wrapper `f.__get__` falls back to `MethodWrapperType`:
-reveal_type(f.__get__.__hash__)  # revealed: <bound method `__hash__` of `MethodWrapperType`>
-
-# Attribute access on the wrapper-descriptor falls back to `WrapperDescriptorType`:
-reveal_type(wrapper_descriptor.__qualname__)  # revealed: @Todo(@property)
-```
-
-We can also bind the free function `f` to an instance of a class `C`:
-
-```py
-class C: ...
-
-bound_method = wrapper_descriptor(f, C(), C)
-
-reveal_type(bound_method)  # revealed: <bound method `f` of `C`>
-```
-
-We can then call it, and the instance of `C` is implicitly passed to the first parameter of `f`
-(`x`):
-
-```py
-reveal_type(bound_method())  # revealed: str
-```
-
-Finally, we test some error cases for the call to the wrapper descriptor:
-
-```py
-# Calling the wrapper descriptor without any arguments is an
-# error: [missing-argument] "No arguments provided for required parameters `self`, `instance`"
-wrapper_descriptor()
-
-# Calling it without the `instance` argument is an also an
-# error: [missing-argument] "No argument provided for required parameter `instance`"
-wrapper_descriptor(f)
-
-# Calling it without the `owner` argument if `instance` is not `None` is an
-# error: [missing-argument] "No argument provided for required parameter `owner`"
-wrapper_descriptor(f, None)
-
-# But calling it with an instance is fine (in this case, the `owner` argument is optional):
-wrapper_descriptor(f, C())
-
-# Calling it with something that is not a `FunctionType` as the first argument is an
-# error: [invalid-argument-type] "Object of type `Literal[1]` cannot be assigned to parameter 1 (`self`) of wrapper descriptor `FunctionType.__get__`; expected type `FunctionType`"
-wrapper_descriptor(1, None, type(f))
-
-# Calling it with something that is not a `type` as the `owner` argument is an
-# error: [invalid-argument-type] "Object of type `Literal[f]` cannot be assigned to parameter 3 (`owner`) of wrapper descriptor `FunctionType.__get__`; expected type `type`"
-wrapper_descriptor(f, None, f)
-
-# Calling it with too many positional arguments is an
-# error: [too-many-positional-arguments] "Too many positional arguments to wrapper descriptor `FunctionType.__get__`: expected 3, got 4"
-wrapper_descriptor(f, None, type(f), "one too many")
-```
-
-[descriptors]: https://docs.python.org/3/howto/descriptor.html
-[precedence chain]: https://github.com/python/cpython/blob/3.13/Objects/typeobject.c#L5393-L5481
-[simple example]: https://docs.python.org/3/howto/descriptor.html#simple-example-a-descriptor-that-returns-a-constant

crates/red_knot_python_semantic/resources/mdtest/diagnostics/invalid_argument_type.md

@@ -1,197 +0,0 @@
-# Invalid argument type diagnostics
-
-<!-- snapshot-diagnostics -->
-
-## Basic
-
-This is a basic test demonstrating that a diagnostic points to the function definition corresponding
-to the invalid argument.
-
-```py
-def foo(x: int) -> int:
-    return x * x
-
-foo("hello")  # error: [invalid-argument-type]
-```
-
-## Different source order
-
-This is like the basic test, except we put the call site above the function definition.
-
-```py
-def bar():
-    foo("hello")  # error: [invalid-argument-type]
-
-def foo(x: int) -> int:
-    return x * x
-```
-
-## Different files
-
-This tests that a diagnostic can point to a function definition in a different file in which an
-invalid call site was found.
-
-`package.py`:
-
-```py
-def foo(x: int) -> int:
-    return x * x
-```
-
-```py
-import package
-
-package.foo("hello")  # error: [invalid-argument-type]
-```
-
-## Many parameters
-
-This checks that a diagnostic renders reasonably when there are multiple parameters.
-
-```py
-def foo(x: int, y: int, z: int) -> int:
-    return x * y * z
-
-foo(1, "hello", 3)  # error: [invalid-argument-type]
-```
-
-## Many parameters across multiple lines
-
-This checks that a diagnostic renders reasonably when there are multiple parameters spread out
-across multiple lines.
-
-```py
-def foo(
-    x: int,
-    y: int,
-    z: int,
-) -> int:
-    return x * y * z
-
-foo(1, "hello", 3)  # error: [invalid-argument-type]
-```
-
-## Many parameters with multiple invalid arguments
-
-This checks that a diagnostic renders reasonably when there are multiple parameters and multiple
-invalid argument types.
-
-```py
-def foo(x: int, y: int, z: int) -> int:
-    return x * y * z
-
-# error: [invalid-argument-type]
-# error: [invalid-argument-type]
-# error: [invalid-argument-type]
-foo("a", "b", "c")
-```
-
-At present (2025-02-18), this renders three different diagnostic messages. But arguably, these could
-all be folded into one diagnostic. Fixing this requires at least better support for multi-spans in
-the diagnostic model and possibly also how diagnostics are emitted by the type checker itself.
-
-## Test calling a function whose type is vendored from `typeshed`
-
-This tests that diagnostic rendering is reasonable when the function being called is from the
-standard library.
-
-```py
-import json
-
-json.loads(5)  # error: [invalid-argument-type]
-```
-
-## Tests for a variety of argument types
-
-These tests check that diagnostic output is reasonable regardless of the kinds of arguments used in
-a function definition.
-
-### Only positional
-
-Tests a function definition with only positional parameters.
-
-```py
-def foo(x: int, y: int, z: int, /) -> int:
-    return x * y * z
-
-foo(1, "hello", 3)  # error: [invalid-argument-type]
-```
-
-### Variadic arguments
-
-Tests a function definition with variadic arguments.
-
-```py
-def foo(*numbers: int) -> int:
-    return len(numbers)
-
-foo(1, 2, 3, "hello", 5)  # error: [invalid-argument-type]
-```
-
-### Keyword only arguments
-
-Tests a function definition with keyword-only arguments.
-
-```py
-def foo(x: int, y: int, *, z: int = 0) -> int:
-    return x * y * z
-
-foo(1, 2, z="hello")  # error: [invalid-argument-type]
-```
-
-### One keyword argument
-
-Tests a function definition with keyword-only arguments.
-
-```py
-def foo(x: int, y: int, z: int = 0) -> int:
-    return x * y * z
-
-foo(1, 2, "hello")  # error: [invalid-argument-type]
-```
-
-### Variadic keyword arguments
-
-```py
-def foo(**numbers: int) -> int:
-    return len(numbers)
-
-foo(a=1, b=2, c=3, d="hello", e=5)  # error: [invalid-argument-type]
-```
-
-### Mix of arguments
-
-Tests a function definition with multiple different kinds of arguments.
-
-```py
-def foo(x: int, /, y: int, *, z: int = 0) -> int:
-    return x * y * z
-
-foo(1, 2, z="hello")  # error: [invalid-argument-type]
-```
-
-### Synthetic arguments
-
-Tests a function call with synthetic arguments.
-
-```py
-class C:
-    def __call__(self, x: int) -> int:
-        return 1
-
-c = C()
-c("wrong")  # error: [invalid-argument-type]
-```
-
-## Calls to methods
-
-Tests that we also see a reference to a function if the callable is a bound method.
-
-```py
-class C:
-    def square(self, x: int) -> int:
-        return x * x
-
-c = C()
-c.square("hello")  # error: [invalid-argument-type]
-```

crates/red_knot_python_semantic/resources/mdtest/diagnostics/unpacking.md

@@ -1,21 +0,0 @@
-# Unpacking
-
-<!-- snapshot-diagnostics -->
-
-## Right hand side not iterable
-
-```py
-a, b = 1  # error: [not-iterable]
-```
-
-## Too many values to unpack
-
-```py
-a, b = (1, 2, 3)  # error: [invalid-assignment]
-```
-
-## Too few values to unpack
-
-```py
-a, b = (1,)  # error: [invalid-assignment]
-```

crates/red_knot_python_semantic/resources/mdtest/diagnostics/unresolved_import.md

@@ -1,87 +0,0 @@
-# Unresolved import diagnostics
-
-<!-- snapshot-diagnostics -->
-
-## Using `from` with an unresolvable module
-
-This example demonstrates the diagnostic when a `from` style import is used with a module that could
-not be found:
-
-```py
-from does_not_exist import add  # error: [unresolved-import]
-
-stat = add(10, 15)
-```
-
-## Using `from` with too many leading dots
-
-This example demonstrates the diagnostic when a `from` style import is used with a presumptively
-valid path, but where there are too many leading dots.
-
-`package/__init__.py`:
-
-```py
-```
-
-`package/foo.py`:
-
-```py
-def add(x, y):
-    return x + y
-```
-
-`package/subpackage/subsubpackage/__init__.py`:
-
-```py
-from ....foo import add  # error: [unresolved-import]
-
-stat = add(10, 15)
-```
-
-## Using `from` with an unknown current module
-
-This is another case handled separately in Red Knot, where a `.` provokes relative module name
-resolution, but where the module name is not resolvable.
-
-```py
-from .does_not_exist import add  # error: [unresolved-import]
-
-stat = add(10, 15)
-```
-
-## Using `from` with an unknown nested module
-
-Like the previous test, but with sub-modules to ensure the span is correct.
-
-```py
-from .does_not_exist.foo.bar import add  # error: [unresolved-import]
-
-stat = add(10, 15)
-```
-
-## Using `from` with a resolvable module but unresolvable item
-
-This ensures that diagnostics for an unresolvable item inside a resolvable import highlight the item
-and not the entire `from ... import ...` statement.
-
-`a.py`:
-
-```py
-does_exist1 = 1
-does_exist2 = 2
-```
-
-```py
-from a import does_exist1, does_not_exist, does_exist2  # error: [unresolved-import]
-```
-
-## An unresolvable import that does not use `from`
-
-This ensures that an unresolvable `import ...` statement highlights just the module name and not the
-entire statement.
-
-```py
-import does_not_exist  # error: [unresolved-import]
-
-x = does_not_exist.foo
-```

crates/red_knot_python_semantic/resources/mdtest/directives/assert_type.md

@@ -78,7 +78,7 @@ def _(a: type[Unknown], b: type[Any]):
 Tuple types with the same elements are the same.
 
 ```py
-from typing_extensions import Any, assert_type
+from typing_extensions import assert_type
 
 from knot_extensions import Unknown
 

crates/red_knot_python_semantic/resources/mdtest/doc/README.md

@@ -1,2 +0,0 @@
-This directory contains user-facing documentation, but also doubles as an extended test suite that
-makes sure that our documentation stays up to date.