Use --lib in uv init in tutorial

## Summary

Use `Unknown | T_inferred` as the type for *undeclared* public symbols.

## Test Plan

- Updated existing tests
- New test for external `__slots__` modifications.
- New tests for external modifications of public symbols.

.config/nextest.toml

@@ -6,3 +6,10 @@ failure-output = "immediate-final"
 fail-fast = false
 
 status-level = "skip"
+
+# Mark tests that take longer than 1s as slow.
+# Terminate after 60s as a stop-gap measure to terminate on deadlock.
+slow-timeout =  { period = "1s", terminate-after = 60 }
+
+# Show slow jobs in the final summary
+final-status-level = "slow"

.gitattributes

@@ -14,5 +14,7 @@ crates/ruff_python_parser/resources/invalid/re_lex_logical_token_mac_eol.py text
 
 crates/ruff_python_parser/resources/inline linguist-generated=true
 
-ruff.schema.json linguist-generated=true text=auto eol=lf
+ruff.schema.json -diff linguist-generated=true text=auto eol=lf
+crates/ruff_python_ast/src/generated.rs -diff linguist-generated=true text=auto eol=lf
+crates/ruff_python_formatter/src/generated.rs -diff linguist-generated=true text=auto eol=lf
 *.md.snap linguist-language=Markdown

.github/ISSUE_TEMPLATE/config.yml

@@ -0,0 +1,2 @@
+# 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/actionlint.yaml

@@ -6,4 +6,5 @@ self-hosted-runner:
   labels:
     - depot-ubuntu-latest-8
     - depot-ubuntu-22.04-16
-    - windows-latest-xlarge
+    - github-windows-2025-x86_64-8
+    - github-windows-2025-x86_64-16

.github/workflows/build-binaries.yml

@@ -23,6 +23,8 @@ concurrency:
   group: ${{ github.workflow }}-${{ github.ref }}
   cancel-in-progress: true
 
+permissions: {}
+
 env:
   PACKAGE_NAME: ruff
   MODULE_NAME: ruff

.github/workflows/build-docker.yml

@@ -51,7 +51,7 @@ jobs:
         env:
           TAG: ${{ inputs.plan != '' && fromJson(inputs.plan).announcement_tag || 'dry-run' }}
         run: |
-          version=$(grep "version = " pyproject.toml | sed -e 's/version = "\(.*\)"/\1/g')
+          version=$(grep -m 1 "^version = " pyproject.toml | sed -e 's/version = "\(.*\)"/\1/g')
           if [ "${TAG}" != "${version}" ]; then
             echo "The input tag does not match the version from pyproject.toml:" >&2
             echo "${TAG}" >&2

.github/workflows/ci.yaml

@@ -1,5 +1,7 @@
 name: CI
 
+permissions: {}
+
 on:
   push:
     branches: [main]
@@ -59,6 +61,7 @@ jobs:
               - Cargo.toml
               - Cargo.lock
               - crates/**
+              - "!crates/red_knot*/**"
               - "!crates/ruff_python_formatter/**"
               - "!crates/ruff_formatter/**"
               - "!crates/ruff_dev/**"
@@ -116,11 +119,11 @@ jobs:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: |
           rustup component add clippy
           rustup target add wasm32-unknown-unknown
-      - uses: Swatinem/rust-cache@v2
       - name: "Clippy"
         run: cargo clippy --workspace --all-targets --all-features --locked -- -D warnings
       - name: "Clippy (wasm)"
@@ -130,12 +133,13 @@ jobs:
     name: "cargo test (linux)"
     runs-on: depot-ubuntu-22.04-16
     needs: determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 20
     steps:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install mold"
@@ -148,7 +152,6 @@ jobs:
         uses: taiki-e/install-action@v2
         with:
           tool: cargo-insta
-      - uses: Swatinem/rust-cache@v2
       - name: "Run tests"
         shell: bash
         env:
@@ -176,12 +179,13 @@ jobs:
     name: "cargo test (linux, release)"
     runs-on: depot-ubuntu-22.04-16
     needs: determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 20
     steps:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install mold"
@@ -194,7 +198,6 @@ jobs:
         uses: taiki-e/install-action@v2
         with:
           tool: cargo-insta
-      - uses: Swatinem/rust-cache@v2
       - name: "Run tests"
         shell: bash
         env:
@@ -203,24 +206,25 @@ jobs:
 
   cargo-test-windows:
     name: "cargo test (windows)"
-    runs-on: windows-latest-xlarge
+    runs-on: github-windows-2025-x86_64-16
     needs: determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 20
     steps:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install cargo nextest"
         uses: taiki-e/install-action@v2
         with:
           tool: cargo-nextest
-      - uses: Swatinem/rust-cache@v2
       - name: "Run tests"
         shell: bash
         env:
+          NEXTEST_PROFILE: "ci"
           # Workaround for <https://github.com/nextest-rs/nextest/issues/1493>.
           RUSTUP_WINDOWS_PATH_ADD_BIN: 1
         run: |
@@ -231,12 +235,13 @@ jobs:
     name: "cargo test (wasm)"
     runs-on: ubuntu-latest
     needs: determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup target add wasm32-unknown-unknown
       - uses: actions/setup-node@v4
@@ -247,7 +252,6 @@ jobs:
       - uses: jetli/wasm-pack-action@v0.4.0
         with:
           version: v0.13.1
-      - uses: Swatinem/rust-cache@v2
       - name: "Test ruff_wasm"
         run: |
           cd crates/ruff_wasm
@@ -266,11 +270,11 @@ jobs:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install mold"
         uses: rui314/setup-mold@v1
-      - uses: Swatinem/rust-cache@v2
       - name: "Build"
         run: cargo build --release --locked
 
@@ -278,7 +282,7 @@ jobs:
     name: "cargo build (msrv)"
     runs-on: ubuntu-latest
     needs: determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 20
     steps:
       - uses: actions/checkout@v4
@@ -289,6 +293,7 @@ jobs:
         with:
           file: "Cargo.toml"
           field: "workspace.package.rust-version"
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         env:
           MSRV: ${{ steps.msrv.outputs.value }}
@@ -303,7 +308,6 @@ jobs:
         uses: taiki-e/install-action@v2
         with:
           tool: cargo-insta
-      - uses: Swatinem/rust-cache@v2
       - name: "Run tests"
         shell: bash
         env:
@@ -321,11 +325,11 @@ jobs:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
-      - name: "Install Rust toolchain"
-        run: rustup show
       - uses: Swatinem/rust-cache@v2
         with:
           workspaces: "fuzz -> target"
+      - name: "Install Rust toolchain"
+        run: rustup show
       - name: "Install cargo-binstall"
         uses: cargo-bins/cargo-binstall@main
         with:
@@ -341,7 +345,7 @@ jobs:
     needs:
       - cargo-test-linux
       - determine_changes
-    if: ${{ needs.determine_changes.outputs.parser == 'true' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && needs.determine_changes.outputs.parser == 'true' }}
     timeout-minutes: 20
     env:
       FORCE_COLOR: 1
@@ -377,15 +381,21 @@ jobs:
     name: "test scripts"
     runs-on: ubuntu-latest
     needs: determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 5
     steps:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup component add rustfmt
-      - uses: Swatinem/rust-cache@v2
+      # Run all code generation scripts, and verify that the current output is
+      # already checked into git.
+      - run: python crates/ruff_python_ast/generate.py
+      - run: python crates/ruff_python_formatter/generate.py
+      - run: test -z "$(git status --porcelain)"
+      # Verify that adding a plugin or rule produces clean code.
       - run: ./scripts/add_rule.py --name DoTheThing --prefix F --code 999 --linter pyflakes
       - run: cargo check
       - run: cargo fmt --all --check
@@ -403,7 +413,7 @@ jobs:
       - determine_changes
     # Only runs on pull requests, since that is the only we way we can find the base version for comparison.
     # Ecosystem check needs linter and/or formatter changes.
-    if: ${{ github.event_name == 'pull_request' && needs.determine_changes.outputs.code == 'true' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && github.event_name == 'pull_request' && needs.determine_changes.outputs.code == 'true' }}
     timeout-minutes: 20
     steps:
       - uses: actions/checkout@v4
@@ -537,6 +547,7 @@ jobs:
     name: "python package"
     runs-on: ubuntu-latest
     timeout-minutes: 20
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') }}
     steps:
       - uses: actions/checkout@v4
         with:
@@ -571,9 +582,9 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: ${{ env.PYTHON_VERSION }}
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup show
-      - uses: Swatinem/rust-cache@v2
       - name: "Install pre-commit"
         run: pip install pre-commit
       - name: "Cache pre-commit"
@@ -605,6 +616,7 @@ jobs:
       - uses: actions/setup-python@v5
         with:
           python-version: "3.13"
+      - uses: Swatinem/rust-cache@v2
       - name: "Add SSH key"
         if: ${{ env.MKDOCS_INSIDERS_SSH_KEY_EXISTS == 'true' }}
         uses: webfactory/ssh-agent@v0.9.0
@@ -614,7 +626,6 @@ jobs:
         run: rustup show
       - name: Install uv
         uses: astral-sh/setup-uv@v5
-      - uses: Swatinem/rust-cache@v2
       - name: "Install Insiders dependencies"
         if: ${{ env.MKDOCS_INSIDERS_SSH_KEY_EXISTS == 'true' }}
         run: uv pip install -r docs/requirements-insiders.txt --system
@@ -638,16 +649,15 @@ jobs:
     name: "formatter instabilities and black similarity"
     runs-on: ubuntu-latest
     needs: determine_changes
-    if: needs.determine_changes.outputs.formatter == 'true' || github.ref == 'refs/heads/main'
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.formatter == 'true' || github.ref == 'refs/heads/main') }}
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@v4
         with:
           persist-credentials: false
+      - uses: Swatinem/rust-cache@v2
       - name: "Install Rust toolchain"
         run: rustup show
-      - name: "Cache rust"
-        uses: Swatinem/rust-cache@v2
       - name: "Run checks"
         run: scripts/formatter_ecosystem_checks.sh
       - name: "Github step summary"
@@ -662,7 +672,7 @@ jobs:
     needs:
       - cargo-test-linux
       - determine_changes
-    if: ${{ needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main' }}
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-test') && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
     steps:
       - uses: extractions/setup-just@v2
         env:
@@ -704,7 +714,7 @@ jobs:
   benchmarks:
     runs-on: ubuntu-22.04
     needs: determine_changes
-    if: ${{ github.repository == 'astral-sh/ruff' && (needs.determine_changes.outputs.code == 'true' || github.ref == 'refs/heads/main') }}
+    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
     steps:
       - name: "Checkout Branch"
@@ -712,6 +722,8 @@ jobs:
         with:
           persist-credentials: false
 
+      - uses: Swatinem/rust-cache@v2
+
       - name: "Install Rust toolchain"
         run: rustup show
 
@@ -720,8 +732,6 @@ jobs:
         with:
           tool: cargo-codspeed
 
-      - uses: Swatinem/rust-cache@v2
-
       - name: "Build benchmarks"
         run: cargo codspeed build --features codspeed -p ruff_benchmark
 

.github/workflows/publish-playground.yml

@@ -49,7 +49,7 @@ jobs:
         working-directory: playground
       - name: "Deploy to Cloudflare Pages"
         if: ${{ env.CF_API_TOKEN_EXISTS == 'true' }}
-        uses: cloudflare/wrangler-action@v3.13.0
+        uses: cloudflare/wrangler-action@v3.13.1
         with:
           apiToken: ${{ secrets.CF_API_TOKEN }}
           accountId: ${{ secrets.CF_ACCOUNT_ID }}

.github/zizmor.yml

@@ -10,3 +10,10 @@ rules:
     ignore:
       - build-docker.yml
       - publish-playground.yml
+  excessive-permissions:
+    # it's hard to test what the impact of removing these ignores would be
+    # without actually running the release workflow...
+    ignore:
+      - build-docker.yml
+      - publish-playground.yml
+      - publish-docs.yml

.gitignore

@@ -29,6 +29,10 @@ tracing.folded
 tracing-flamechart.svg
 tracing-flamegraph.svg
 
+# insta
+.rs.pending-snap
+
+
 ###
 # Rust.gitignore
 ###

.pre-commit-config.yaml

@@ -4,7 +4,7 @@ exclude: |
   (?x)^(
     .github/workflows/release.yml|
     crates/red_knot_vendored/vendor/.*|
-    crates/red_knot_workspace/resources/.*|
+    crates/red_knot_project/resources/.*|
     crates/ruff_linter/resources/.*|
     crates/ruff_linter/src/rules/.*/snapshots/.*|
     crates/ruff_notebook/resources/.*|
@@ -73,7 +73,7 @@ repos:
         pass_filenames: false # This makes it a lot faster
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.9.1
+    rev: v0.9.2
     hooks:
       - id: ruff-format
       - id: ruff
@@ -91,7 +91,7 @@ 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: v1.0.1
+    rev: v1.2.2
     hooks:
       - id: zizmor
 
@@ -103,7 +103,7 @@ repos:
   # `actionlint` hook, for verifying correct syntax in GitHub Actions workflows.
   # Some additional configuration for `actionlint` can be found in `.github/actionlint.yaml`.
   - repo: https://github.com/rhysd/actionlint
-    rev: v1.7.6
+    rev: v1.7.7
     hooks:
       - id: actionlint
         stages:

CHANGELOG.md

@@ -1,5 +1,65 @@
 # Changelog
 
+## 0.9.3
+
+### Preview features
+
+- \[`airflow`\] Argument `fail_stop` in DAG has been renamed as `fail_fast` (`AIR302`) ([#15633](https://github.com/astral-sh/ruff/pull/15633))
+- \[`airflow`\] Extend `AIR303` with more symbols ([#15611](https://github.com/astral-sh/ruff/pull/15611))
+- \[`flake8-bandit`\] Report all references to suspicious functions (`S3`) ([#15541](https://github.com/astral-sh/ruff/pull/15541))
+- \[`flake8-pytest-style`\] Do not emit diagnostics for empty `for` loops (`PT012`, `PT031`) ([#15542](https://github.com/astral-sh/ruff/pull/15542))
+- \[`flake8-simplify`\] Avoid double negations (`SIM103`) ([#15562](https://github.com/astral-sh/ruff/pull/15562))
+- \[`pyflakes`\] Fix infinite loop with unused local import in `__init__.py` (`F401`) ([#15517](https://github.com/astral-sh/ruff/pull/15517))
+- \[`pylint`\] Do not report methods with only one `EM101`-compatible `raise` (`PLR6301`) ([#15507](https://github.com/astral-sh/ruff/pull/15507))
+- \[`pylint`\] Implement `redefined-slots-in-subclass` (`W0244`) ([#9640](https://github.com/astral-sh/ruff/pull/9640))
+- \[`pyupgrade`\] Add rules to use PEP 695 generics in classes and functions (`UP046`, `UP047`) ([#15565](https://github.com/astral-sh/ruff/pull/15565), [#15659](https://github.com/astral-sh/ruff/pull/15659))
+- \[`refurb`\] Implement `for-loop-writes` (`FURB122`) ([#10630](https://github.com/astral-sh/ruff/pull/10630))
+- \[`ruff`\] Implement `needless-else` clause (`RUF047`) ([#15051](https://github.com/astral-sh/ruff/pull/15051))
+- \[`ruff`\] Implement `starmap-zip` (`RUF058`) ([#15483](https://github.com/astral-sh/ruff/pull/15483))
+
+### Rule changes
+
+- \[`flake8-bugbear`\] Do not raise error if keyword argument is present and target-python version is less or equals than 3.9 (`B903`) ([#15549](https://github.com/astral-sh/ruff/pull/15549))
+- \[`flake8-comprehensions`\] strip parentheses around generators in `unnecessary-generator-set` (`C401`) ([#15553](https://github.com/astral-sh/ruff/pull/15553))
+- \[`flake8-pytest-style`\] Rewrite references to `.exception` (`PT027`) ([#15680](https://github.com/astral-sh/ruff/pull/15680))
+- \[`flake8-simplify`\] Mark fixes as unsafe (`SIM201`, `SIM202`) ([#15626](https://github.com/astral-sh/ruff/pull/15626))
+- \[`flake8-type-checking`\] Fix some safe fixes being labeled unsafe (`TC006`,`TC008`) ([#15638](https://github.com/astral-sh/ruff/pull/15638))
+- \[`isort`\] Omit trailing whitespace in `unsorted-imports` (`I001`) ([#15518](https://github.com/astral-sh/ruff/pull/15518))
+- \[`pydoclint`\] Allow ignoring one line docstrings for `DOC` rules ([#13302](https://github.com/astral-sh/ruff/pull/13302))
+- \[`pyflakes`\] Apply redefinition fixes by source code order (`F811`) ([#15575](https://github.com/astral-sh/ruff/pull/15575))
+- \[`pyflakes`\] Avoid removing too many imports in `redefined-while-unused` (`F811`) ([#15585](https://github.com/astral-sh/ruff/pull/15585))
+- \[`pyflakes`\] Group redefinition fixes by source statement (`F811`) ([#15574](https://github.com/astral-sh/ruff/pull/15574))
+- \[`pylint`\] Include name of base class in message for `redefined-slots-in-subclass` (`W0244`) ([#15559](https://github.com/astral-sh/ruff/pull/15559))
+- \[`ruff`\] Update fix for `RUF055` to use `var == value` ([#15605](https://github.com/astral-sh/ruff/pull/15605))
+
+### Formatter
+
+- Fix bracket spacing for single-element tuples in f-string expressions ([#15537](https://github.com/astral-sh/ruff/pull/15537))
+- Fix unstable f-string formatting for expressions containing a trailing comma ([#15545](https://github.com/astral-sh/ruff/pull/15545))
+
+### Performance
+
+- Avoid quadratic membership check in import fixes ([#15576](https://github.com/astral-sh/ruff/pull/15576))
+
+### Server
+
+- Allow `unsafe-fixes` settings for code actions ([#15666](https://github.com/astral-sh/ruff/pull/15666))
+
+### Bug fixes
+
+- \[`flake8-bandit`\] Add missing single-line/dotall regex flag (`S608`) ([#15654](https://github.com/astral-sh/ruff/pull/15654))
+- \[`flake8-import-conventions`\] Fix infinite loop between `ICN001` and `I002` (`ICN001`) ([#15480](https://github.com/astral-sh/ruff/pull/15480))
+- \[`flake8-simplify`\] Do not emit diagnostics for expressions inside string type annotations (`SIM222`, `SIM223`) ([#15405](https://github.com/astral-sh/ruff/pull/15405))
+- \[`pyflakes`\] Treat arguments passed to the `default=` parameter of `TypeVar` as type expressions (`F821`) ([#15679](https://github.com/astral-sh/ruff/pull/15679))
+- \[`pyupgrade`\] Avoid syntax error when the iterable is a non-parenthesized tuple (`UP028`) ([#15543](https://github.com/astral-sh/ruff/pull/15543))
+- \[`ruff`\] Exempt `NewType` calls where the original type is immutable (`RUF009`) ([#15588](https://github.com/astral-sh/ruff/pull/15588))
+- Preserve raw string prefix and escapes in all codegen fixes ([#15694](https://github.com/astral-sh/ruff/pull/15694))
+
+### Documentation
+
+- Generate documentation redirects for lowercase rule codes ([#15564](https://github.com/astral-sh/ruff/pull/15564))
+- `TRY300`: Add some extra notes on not catching exceptions you didn't expect ([#15036](https://github.com/astral-sh/ruff/pull/15036))
+
 ## 0.9.2
 
 ### Preview features

Cargo.lock

@@ -212,9 +212,9 @@ checksum = "bef38d45163c2f1dde094a7dfd33ccf595c92905c8f8f4fdc18d06fb1037718a"
 
 [[package]]
 name = "bitflags"
-version = "2.7.0"
+version = "2.8.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1be3f42a67d6d345ecd59f675f3f012d6974981560836e938c22b424b85ce1be"
+checksum = "8f68f53c83ab957f72c32642f3868eec03eb974d1fb82e453128456482613d36"
 
 [[package]]
 name = "block-buffer"
@@ -477,7 +477,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "117725a109d387c937a1533ce01b450cbde6b88abceea8473c4d7a85853cda3c"
 dependencies = [
  "lazy_static",
- "windows-sys 0.48.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
@@ -1062,7 +1062,7 @@ version = "0.9.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "0bf760ebf69878d9fd8f110c89703d90ce35095324d1f1edcb595c63945ee757"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "ignore",
  "walkdir",
 ]
@@ -1343,9 +1343,9 @@ dependencies = [
 
 [[package]]
 name = "indexmap"
-version = "2.7.0"
+version = "2.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "62f822373a4fe84d4bb149bf54e584a7f4abec90e072ed49cda0edea5b95471f"
+checksum = "8c9c992b02b5b4c94ea26e32fe5bccb7aa7d9f390ab5c1221ff895bc7ea8b652"
 dependencies = [
  "equivalent",
  "hashbrown 0.15.2",
@@ -1374,11 +1374,11 @@ checksum = "b248f5224d1d606005e02c97f5aa4e88eeb230488bcc03bc9ca4d7991399f2b5"
 
 [[package]]
 name = "inotify"
-version = "0.10.2"
+version = "0.11.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "fdd168d97690d0b8c412d6b6c10360277f4d7ee495c5d0d5d5fe0854923255cc"
+checksum = "f37dccff2791ab604f9babef0ba14fbe0be30bd368dc541e2b08d07c8aa908f3"
 dependencies = [
- "bitflags 1.3.2",
+ "bitflags 2.8.0",
  "inotify-sys",
  "libc",
 ]
@@ -1422,15 +1422,6 @@ dependencies = [
  "serde_json",
 ]
 
-[[package]]
-name = "instant"
-version = "0.1.12"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7a5bbe824c507c5da5956355e86a746d82e0e1464f65d862cc5e71da70e94b2c"
-dependencies = [
- "cfg-if",
-]
-
 [[package]]
 name = "is-docker"
 version = "0.2.0"
@@ -1610,7 +1601,7 @@ version = "0.1.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "c0ff37bd590ca25063e35af745c343cb7a0271906fb7b37e4813e8f79f00268d"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "libc",
  "redox_syscall 0.5.3",
 ]
@@ -1657,9 +1648,9 @@ dependencies = [
 
 [[package]]
 name = "log"
-version = "0.4.22"
+version = "0.4.25"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a7a70ba024b9dc04c27ea2f0c0548feb474ec5c54bba33a7f72f873a39d07b24"
+checksum = "04cbf5b083de1c7e0222a7a51dbfdba1cbe1c6ab0b15e29fff3f6c077fd9cd9f"
 
 [[package]]
 name = "lsp-server"
@@ -1781,7 +1772,7 @@ version = "0.29.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "71e2746dc3a24dd78b3cfcb7be93368c6de9963d30f43a6a73998a9cf4b17b46"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "cfg-if",
  "cfg_aliases",
  "libc",
@@ -1805,11 +1796,11 @@ checksum = "61807f77802ff30975e01f4f071c8ba10c022052f98b3294119f3e615d13e5be"
 
 [[package]]
 name = "notify"
-version = "7.0.0"
+version = "8.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c533b4c39709f9ba5005d8002048266593c1cfaf3c5f0739d5b8ab0c6c504009"
+checksum = "2fee8403b3d66ac7b26aee6e40a897d85dc5ce26f44da36b8b73e987cc52e943"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "filetime",
  "fsevent-sys",
  "inotify",
@@ -1819,17 +1810,14 @@ dependencies = [
  "mio",
  "notify-types",
  "walkdir",
- "windows-sys 0.52.0",
+ "windows-sys 0.59.0",
 ]
 
 [[package]]
 name = "notify-types"
-version = "1.0.0"
+version = "2.0.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7393c226621f817964ffb3dc5704f9509e107a8b024b489cc2c1b217378785df"
-dependencies = [
- "instant",
-]
+checksum = "5e0826a989adedc2a244799e823aece04662b66609d96af8dff7ac6df9a8925d"
 
 [[package]]
 name = "nu-ansi-term"
@@ -1895,9 +1883,9 @@ checksum = "04744f49eae99ab78e0d5c0b603ab218f515ea8cfe5a456d7629ad883a3b6e7d"
 
 [[package]]
 name = "ordermap"
-version = "0.5.4"
+version = "0.5.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "f80a48eb68b6a7da9829b8b0429011708f775af80676a91063d023a66a656106"
+checksum = "c55fdf45a2b1e929e3656d404395767e05c98b6ebd8157eb31e370077d545160"
 dependencies = [
  "indexmap",
 ]
@@ -2336,25 +2324,56 @@ dependencies = [
  "crossbeam",
  "ctrlc",
  "filetime",
+ "insta",
+ "insta-cmd",
  "rayon",
+ "red_knot_project",
  "red_knot_python_semantic",
  "red_knot_server",
- "red_knot_workspace",
+ "regex",
  "ruff_db",
+ "ruff_python_trivia",
  "salsa",
  "tempfile",
+ "toml",
  "tracing",
  "tracing-flame",
  "tracing-subscriber",
  "tracing-tree",
 ]
 
+[[package]]
+name = "red_knot_project"
+version = "0.0.0"
+dependencies = [
+ "anyhow",
+ "crossbeam",
+ "glob",
+ "insta",
+ "notify",
+ "pep440_rs",
+ "rayon",
+ "red_knot_python_semantic",
+ "red_knot_vendored",
+ "ruff_cache",
+ "ruff_db",
+ "ruff_macros",
+ "ruff_python_ast",
+ "ruff_text_size",
+ "rustc-hash 2.1.0",
+ "salsa",
+ "serde",
+ "thiserror 2.0.11",
+ "toml",
+ "tracing",
+]
+
 [[package]]
 name = "red_knot_python_semantic"
 version = "0.0.0"
 dependencies = [
  "anyhow",
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "camino",
  "compact_str",
  "countme",
@@ -2401,7 +2420,7 @@ dependencies = [
  "libc",
  "lsp-server",
  "lsp-types",
- "red_knot_workspace",
+ "red_knot_project",
  "ruff_db",
  "ruff_notebook",
  "ruff_python_ast",
@@ -2456,39 +2475,14 @@ dependencies = [
  "console_log",
  "js-sys",
  "log",
+ "red_knot_project",
  "red_knot_python_semantic",
- "red_knot_workspace",
  "ruff_db",
  "ruff_notebook",
  "wasm-bindgen",
  "wasm-bindgen-test",
 ]
 
-[[package]]
-name = "red_knot_workspace"
-version = "0.0.0"
-dependencies = [
- "anyhow",
- "crossbeam",
- "glob",
- "insta",
- "notify",
- "pep440_rs",
- "rayon",
- "red_knot_python_semantic",
- "red_knot_vendored",
- "ruff_cache",
- "ruff_db",
- "ruff_python_ast",
- "ruff_text_size",
- "rustc-hash 2.1.0",
- "salsa",
- "serde",
- "thiserror 2.0.11",
- "toml",
- "tracing",
-]
-
 [[package]]
 name = "redox_syscall"
 version = "0.4.1"
@@ -2504,7 +2498,7 @@ version = "0.5.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "2a908a6e00f1fdd0dfd9c0eb08ce85126f6d8bbda50017e74bc4a4b7d4a926a4"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
 ]
 
 [[package]]
@@ -2590,13 +2584,13 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.9.2"
+version = "0.9.3"
 dependencies = [
  "anyhow",
  "argfile",
  "assert_fs",
  "bincode",
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "cachedir",
  "chrono",
  "clap",
@@ -2668,8 +2662,8 @@ dependencies = [
  "criterion",
  "mimalloc",
  "rayon",
+ "red_knot_project",
  "red_knot_python_semantic",
- "red_knot_workspace",
  "ruff_db",
  "ruff_linter",
  "ruff_python_ast",
@@ -2824,11 +2818,11 @@ dependencies = [
 
 [[package]]
 name = "ruff_linter"
-version = "0.9.2"
+version = "0.9.3"
 dependencies = [
  "aho-corasick",
  "anyhow",
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "chrono",
  "clap",
  "colored 3.0.0",
@@ -2918,7 +2912,7 @@ name = "ruff_python_ast"
 version = "0.0.0"
 dependencies = [
  "aho-corasick",
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "compact_str",
  "is-macro",
  "itertools 0.14.0",
@@ -3000,7 +2994,7 @@ dependencies = [
 name = "ruff_python_literal"
 version = "0.0.0"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "itertools 0.14.0",
  "ruff_python_ast",
  "unic-ucd-category",
@@ -3011,7 +3005,7 @@ name = "ruff_python_parser"
 version = "0.0.0"
 dependencies = [
  "anyhow",
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "bstr",
  "compact_str",
  "insta",
@@ -3043,7 +3037,7 @@ dependencies = [
 name = "ruff_python_semantic"
 version = "0.0.0"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "is-macro",
  "ruff_cache",
  "ruff_index",
@@ -3062,7 +3056,7 @@ dependencies = [
 name = "ruff_python_stdlib"
 version = "0.0.0"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "unicode-ident",
 ]
 
@@ -3141,7 +3135,7 @@ dependencies = [
 
 [[package]]
 name = "ruff_wasm"
-version = "0.9.2"
+version = "0.9.3"
 dependencies = [
  "console_error_panic_hook",
  "console_log",
@@ -3229,7 +3223,7 @@ version = "0.38.40"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "99e4ea3e1cdc4b559b8e5650f9c8e5998e3e5c1343b4eaf034565f32318d63c0"
 dependencies = [
- "bitflags 2.7.0",
+ "bitflags 2.8.0",
  "errno",
  "libc",
  "linux-raw-sys",
@@ -3412,9 +3406,9 @@ dependencies = [
 
 [[package]]
 name = "serde_json"
-version = "1.0.135"
+version = "1.0.137"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "2b0d7ba2887406110130a978386c4e1befb98c674b4fba677954e4db976630d9"
+checksum = "930cfb6e6abf99298aaad7d29abbef7a9999a9a8806a40088f55f0dcec03146b"
 dependencies = [
  "itoa",
  "memchr",
@@ -3511,9 +3505,9 @@ checksum = "0fda2ff0d084019ba4d7c6f371c95d8fd75ce3524c3cb8fb653a3023f6323e64"
 
 [[package]]
 name = "similar"
-version = "2.6.0"
+version = "2.7.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1de1d4f81173b03af4c0cbed3c898f6bff5b870e4a7f5d6f4057d62a7a4b686e"
+checksum = "bbbb5d9659141646ae647b42fe094daf6c6192d1620870b449d9557f748b2daa"
 
 [[package]]
 name = "siphasher"
@@ -3933,9 +3927,9 @@ dependencies = [
 
 [[package]]
 name = "tracing-indicatif"
-version = "0.3.8"
+version = "0.3.9"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "74ba258e9de86447f75edf6455fded8e5242704c6fccffe7bf8d7fb6daef1180"
+checksum = "8201ca430e0cd893ef978226fd3516c06d9c494181c8bf4e5b32e30ed4b40aa1"
 dependencies = [
  "indicatif",
  "tracing",
@@ -4176,9 +4170,9 @@ checksum = "711b9620af191e0cdc7468a8d14e709c3dcdb115b36f838e601583af800a370a"
 
 [[package]]
 name = "uuid"
-version = "1.11.1"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "b913a3b5fe84142e269d63cc62b64319ccaf89b748fc31fe025177f767a756c4"
+checksum = "744018581f9a3454a9e15beb8a33b017183f1e7c0cd170232a2d1453b23a51c4"
 dependencies = [
  "getrandom",
  "rand",
@@ -4188,9 +4182,9 @@ dependencies = [
 
 [[package]]
 name = "uuid-macro-internal"
-version = "1.11.1"
+version = "1.12.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c91084647266237a48351d05d55dee65bba9e1b597f555fcf54680f820284a1c"
+checksum = "144b419c512fdd5eaa4c2998813e32aaab2b257746ee038de93985a99635501d"
 dependencies = [
  "proc-macro2",
  "quote",

Cargo.toml

@@ -41,7 +41,7 @@ ruff_workspace = { path = "crates/ruff_workspace" }
 red_knot_python_semantic = { path = "crates/red_knot_python_semantic" }
 red_knot_server = { path = "crates/red_knot_server" }
 red_knot_test = { path = "crates/red_knot_test" }
-red_knot_workspace = { path = "crates/red_knot_workspace", default-features = false }
+red_knot_project = { path = "crates/red_knot_project", default-features = false }
 
 aho-corasick = { version = "1.1.3" }
 anstream = { version = "0.6.18" }
@@ -105,7 +105,7 @@ matchit = { version = "0.8.1" }
 memchr = { version = "2.7.1" }
 mimalloc = { version = "0.1.39" }
 natord = { version = "1.0.9" }
-notify = { version = "7.0.0" }
+notify = { version = "8.0.0" }
 ordermap = { version = "0.5.0" }
 path-absolutize = { version = "3.1.1" }
 path-slash = { version = "0.2.1" }

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/0.9.2/install.sh | sh
-powershell -c "irm https://astral.sh/ruff/0.9.2/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: v0.9.2
+  rev: v0.9.3
   hooks:
     # Run the linter.
     - id: ruff

crates/red_knot/Cargo.toml

@@ -13,7 +13,7 @@ license.workspace = true
 
 [dependencies]
 red_knot_python_semantic = { workspace = true }
-red_knot_workspace = { workspace = true, features = ["zstd"] }
+red_knot_project = { workspace = true, features = ["zstd"] }
 red_knot_server = { workspace = true }
 ruff_db = { workspace = true, features = ["os", "cache"] }
 
@@ -32,9 +32,15 @@ tracing-flame = { workspace = true }
 tracing-tree = { workspace = true }
 
 [dev-dependencies]
-filetime = { workspace = true }
-tempfile = { workspace = true }
 ruff_db = { workspace = true, features = ["testing"] }
+ruff_python_trivia = { workspace = true }
+
+insta = { workspace = true, features = ["filters"] }
+insta-cmd = { workspace = true }
+filetime = { workspace = true }
+regex = { workspace = true }
+tempfile = { workspace = true }
+toml = { workspace = true }
 
 [lints]
 workspace = true

crates/red_knot/src/main.rs

@@ -6,13 +6,12 @@ use clap::Parser;
 use colored::Colorize;
 use crossbeam::channel as crossbeam_channel;
 use python_version::PythonVersion;
-use red_knot_python_semantic::SitePackages;
+use red_knot_project::metadata::options::{EnvironmentOptions, Options};
+use red_knot_project::metadata::value::{RangedValue, RelativePathBuf};
+use red_knot_project::watch;
+use red_knot_project::watch::ProjectWatcher;
+use red_knot_project::{ProjectDatabase, ProjectMetadata};
 use red_knot_server::run_server;
-use red_knot_workspace::db::ProjectDatabase;
-use red_knot_workspace::project::settings::Configuration;
-use red_knot_workspace::project::ProjectMetadata;
-use red_knot_workspace::watch;
-use red_knot_workspace::watch::ProjectWatcher;
 use ruff_db::diagnostic::Diagnostic;
 use ruff_db::system::{OsSystem, System, SystemPath, SystemPathBuf};
 use salsa::plumbing::ZalsaDatabase;
@@ -71,31 +70,24 @@ struct Args {
 }
 
 impl Args {
-    fn to_configuration(&self, cli_cwd: &SystemPath) -> Configuration {
-        let mut configuration = Configuration::default();
-
-        if let Some(python_version) = self.python_version {
-            configuration.python_version = Some(python_version.into());
+    fn to_options(&self) -> Options {
+        Options {
+            environment: Some(EnvironmentOptions {
+                python_version: self
+                    .python_version
+                    .map(|version| RangedValue::cli(version.into())),
+                venv_path: self.venv_path.as_ref().map(RelativePathBuf::cli),
+                typeshed: self.typeshed.as_ref().map(RelativePathBuf::cli),
+                extra_paths: self.extra_search_path.as_ref().map(|extra_search_paths| {
+                    extra_search_paths
+                        .iter()
+                        .map(RelativePathBuf::cli)
+                        .collect()
+                }),
+                ..EnvironmentOptions::default()
+            }),
+            ..Default::default()
         }
-
-        if let Some(venv_path) = &self.venv_path {
-            configuration.search_paths.site_packages = Some(SitePackages::Derived {
-                venv_path: SystemPath::absolute(venv_path, cli_cwd),
-            });
-        }
-
-        if let Some(typeshed) = &self.typeshed {
-            configuration.search_paths.typeshed = Some(SystemPath::absolute(typeshed, cli_cwd));
-        }
-
-        if let Some(extra_search_paths) = &self.extra_search_path {
-            configuration.search_paths.extra_paths = extra_search_paths
-                .iter()
-                .map(|path| Some(SystemPath::absolute(path, cli_cwd)))
-                .collect();
-        }
-
-        configuration
     }
 }
 
@@ -163,19 +155,14 @@ fn run() -> anyhow::Result<ExitStatus> {
         .transpose()?
         .unwrap_or_else(|| cli_base_path.clone());
 
-    let system = OsSystem::new(cwd.clone());
-    let cli_configuration = args.to_configuration(&cwd);
-    let workspace_metadata = ProjectMetadata::discover(
-        system.current_directory(),
-        &system,
-        Some(&cli_configuration),
-    )?;
+    let system = OsSystem::new(cwd);
+    let cli_options = args.to_options();
+    let mut workspace_metadata = ProjectMetadata::discover(system.current_directory(), &system)?;
+    workspace_metadata.apply_cli_options(cli_options.clone());
 
-    // TODO: Use the `program_settings` to compute the key for the database's persistent
-    //   cache and load the cache if it exists.
     let mut db = ProjectDatabase::new(workspace_metadata, system)?;
 
-    let (main_loop, main_loop_cancellation_token) = MainLoop::new(cli_configuration);
+    let (main_loop, main_loop_cancellation_token) = MainLoop::new(cli_options);
 
     // Listen to Ctrl+C and abort the watch mode.
     let main_loop_cancellation_token = Mutex::new(Some(main_loop_cancellation_token));
@@ -228,11 +215,11 @@ struct MainLoop {
     /// The file system watcher, if running in watch mode.
     watcher: Option<ProjectWatcher>,
 
-    cli_configuration: Configuration,
+    cli_options: Options,
 }
 
 impl MainLoop {
-    fn new(cli_configuration: Configuration) -> (Self, MainLoopCancellationToken) {
+    fn new(cli_options: Options) -> (Self, MainLoopCancellationToken) {
         let (sender, receiver) = crossbeam_channel::bounded(10);
 
         (
@@ -240,7 +227,7 @@ impl MainLoop {
                 sender: sender.clone(),
                 receiver,
                 watcher: None,
-                cli_configuration,
+                cli_options,
             },
             MainLoopCancellationToken { sender },
         )
@@ -324,7 +311,7 @@ impl MainLoop {
                 MainLoopMessage::ApplyChanges(changes) => {
                     revision += 1;
                     // Automatically cancels any pending queries and waits for them to complete.
-                    db.apply_changes(changes, Some(&self.cli_configuration));
+                    db.apply_changes(changes, Some(&self.cli_options));
                     if let Some(watcher) = self.watcher.as_mut() {
                         watcher.update(db);
                     }

crates/red_knot/tests/cli.rs

@@ -0,0 +1,327 @@
+use anyhow::Context;
+use insta::Settings;
+use insta_cmd::{assert_cmd_snapshot, get_cargo_bin};
+use std::path::{Path, PathBuf};
+use std::process::Command;
+use tempfile::TempDir;
+
+/// Specifying an option on the CLI should take precedence over the same setting in the
+/// project's configuration.
+#[test]
+fn config_override() -> anyhow::Result<()> {
+    let case = TestCase::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.knot.environment]
+            python-version = "3.11"
+            "#,
+        ),
+        (
+            "test.py",
+            r#"
+            import sys
+
+            # Access `sys.last_exc` that was only added in Python 3.12
+            print(sys.last_exc)
+            "#,
+        ),
+    ])?;
+
+    case.insta_settings().bind(|| {
+        assert_cmd_snapshot!(case.command(), @r"
+            success: false
+            exit_code: 1
+            ----- stdout -----
+            error[lint:unresolved-attribute] <temp_dir>/test.py:5:7 Type `<module 'sys'>` has no attribute `last_exc`
+
+            ----- stderr -----
+        ");
+
+        assert_cmd_snapshot!(case.command().arg("--python-version").arg("3.12"), @r"
+            success: true
+            exit_code: 0
+            ----- stdout -----
+
+            ----- stderr -----
+        ");
+    });
+
+    Ok(())
+}
+
+/// Paths specified on the CLI are relative to the current working directory and not the project root.
+///
+/// We test this by adding an extra search path from the CLI to the libs directory when
+/// running the CLI from the child directory (using relative paths).
+///
+/// Project layout:
+/// ```
+///  - libs
+///    |- utils.py
+///  - child
+///    | - test.py
+/// - pyproject.toml
+/// ```
+///
+/// And the command is run in the `child` directory.
+#[test]
+fn cli_arguments_are_relative_to_the_current_directory() -> anyhow::Result<()> {
+    let case = TestCase::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.knot.environment]
+            python-version = "3.11"
+            "#,
+        ),
+        (
+            "libs/utils.py",
+            r#"
+            def add(a: int, b: int) -> int:
+                a + b
+            "#,
+        ),
+        (
+            "child/test.py",
+            r#"
+            from utils import add
+
+            stat = add(10, 15)
+            "#,
+        ),
+    ])?;
+
+    case.insta_settings().bind(|| {
+        // Make sure that the CLI fails when the `libs` directory is not in the search path.
+        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`
+
+            ----- 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 -----
+
+            ----- stderr -----
+        ");
+    });
+
+    Ok(())
+}
+
+/// Paths specified in a configuration file are relative to the project root.
+///
+/// We test this by adding `libs` (as a relative path) to the extra search path in the configuration and run
+/// the CLI from a subdirectory.
+///
+/// Project layout:
+/// ```
+///  - libs
+///    |- utils.py
+///  - child
+///    | - test.py
+/// - pyproject.toml
+/// ```
+#[test]
+fn paths_in_configuration_files_are_relative_to_the_project_root() -> anyhow::Result<()> {
+    let case = TestCase::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.knot.environment]
+            python-version = "3.11"
+            extra-paths = ["libs"]
+            "#,
+        ),
+        (
+            "libs/utils.py",
+            r#"
+            def add(a: int, b: int) -> int:
+                a + b
+            "#,
+        ),
+        (
+            "child/test.py",
+            r#"
+            from utils import add
+
+            stat = add(10, 15)
+            "#,
+        ),
+    ])?;
+
+    case.insta_settings().bind(|| {
+        assert_cmd_snapshot!(case.command().current_dir(case.project_dir().join("child")), @r"
+            success: true
+            exit_code: 0
+            ----- stdout -----
+
+            ----- stderr -----
+        ");
+    });
+
+    Ok(())
+}
+
+/// The rule severity can be changed in the configuration file
+#[test]
+fn rule_severity() -> anyhow::Result<()> {
+    let case = TestCase::with_file(
+        "test.py",
+        r#"
+            y = 4 / 0
+
+            for a in range(0, y):
+                x = a
+
+            print(x)  # possibly-unresolved-reference
+            "#,
+    )?;
+
+    case.insta_settings().bind(|| {
+        // 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 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
+
+            ----- stderr -----
+        ");
+
+        case.write_file("pyproject.toml", r#"
+            [tool.knot.rules]
+            division-by-zero = "warn" # demote to warn
+            possibly-unresolved-reference = "ignore"
+        "#)?;
+
+        assert_cmd_snapshot!(case.command(), @r"
+            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
+
+            ----- stderr -----
+        ");
+
+        Ok(())
+    })
+}
+
+/// Red Knot warns about unknown rules
+#[test]
+fn unknown_rules() -> anyhow::Result<()> {
+    let case = TestCase::with_files([
+        (
+            "pyproject.toml",
+            r#"
+            [tool.knot.rules]
+            division-by-zer = "warn" # incorrect rule name
+            "#,
+        ),
+        ("test.py", "print(10)"),
+    ])?;
+
+    case.insta_settings().bind(|| {
+        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`
+
+            ----- stderr -----
+        ");
+    });
+
+    Ok(())
+}
+
+struct TestCase {
+    _temp_dir: TempDir,
+    project_dir: PathBuf,
+}
+
+impl TestCase {
+    fn new() -> anyhow::Result<Self> {
+        let temp_dir = TempDir::new()?;
+
+        // Canonicalize the tempdir path because macos uses symlinks for tempdirs
+        // and that doesn't play well with our snapshot filtering.
+        let project_dir = temp_dir
+            .path()
+            .canonicalize()
+            .context("Failed to canonicalize project path")?;
+
+        Ok(Self {
+            project_dir,
+            _temp_dir: temp_dir,
+        })
+    }
+
+    fn with_files<'a>(files: impl IntoIterator<Item = (&'a str, &'a str)>) -> anyhow::Result<Self> {
+        let case = Self::new()?;
+        case.write_files(files)?;
+        Ok(case)
+    }
+
+    fn with_file(path: impl AsRef<Path>, content: &str) -> anyhow::Result<Self> {
+        let case = Self::new()?;
+        case.write_file(path, content)?;
+        Ok(case)
+    }
+
+    fn write_files<'a>(
+        &self,
+        files: impl IntoIterator<Item = (&'a str, &'a str)>,
+    ) -> anyhow::Result<()> {
+        for (path, content) in files {
+            self.write_file(path, content)?;
+        }
+
+        Ok(())
+    }
+
+    fn write_file(&self, path: impl AsRef<Path>, content: &str) -> anyhow::Result<()> {
+        let path = path.as_ref();
+        let path = self.project_dir.join(path);
+
+        if let Some(parent) = path.parent() {
+            std::fs::create_dir_all(parent)
+                .with_context(|| format!("Failed to create directory `{}`", parent.display()))?;
+        }
+        std::fs::write(&path, &*ruff_python_trivia::textwrap::dedent(content))
+            .with_context(|| format!("Failed to write file `{path}`", path = path.display()))?;
+
+        Ok(())
+    }
+
+    fn project_dir(&self) -> &Path {
+        &self.project_dir
+    }
+
+    // Returns the insta filters to escape paths in snapshots
+    fn insta_settings(&self) -> Settings {
+        let mut settings = insta::Settings::clone_current();
+        settings.add_filter(&tempdir_filter(&self.project_dir), "<temp_dir>/");
+        settings.add_filter(r#"\\(\w\w|\s|\.|")"#, "/$1");
+        settings
+    }
+
+    fn command(&self) -> Command {
+        let mut command = Command::new(get_cargo_bin("red_knot"));
+        command.current_dir(&self.project_dir);
+        command
+    }
+}
+
+fn tempdir_filter(path: &Path) -> String {
+    format!(r"{}\\?/?", regex::escape(path.to_str().unwrap()))
+}

crates/red_knot/tests/file_watching.rs

@@ -4,11 +4,12 @@ use std::io::Write;
 use std::time::{Duration, Instant};
 
 use anyhow::{anyhow, Context};
-use red_knot_python_semantic::{resolve_module, ModuleName, Program, PythonVersion, SitePackages};
-use red_knot_workspace::db::{Db, ProjectDatabase};
-use red_knot_workspace::project::settings::{Configuration, SearchPathConfiguration};
-use red_knot_workspace::project::ProjectMetadata;
-use red_knot_workspace::watch::{directory_watcher, ChangeEvent, ProjectWatcher};
+use red_knot_project::metadata::options::{EnvironmentOptions, Options};
+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, PythonVersion};
 use ruff_db::files::{system_path_to_file, File, FileError};
 use ruff_db::source::source_text;
 use ruff_db::system::{OsSystem, SystemPath, SystemPathBuf};
@@ -22,7 +23,6 @@ struct TestCase {
     /// We need to hold on to it in the test case or the temp files get deleted.
     _temp_dir: tempfile::TempDir,
     root_dir: SystemPathBuf,
-    configuration: Configuration,
 }
 
 impl TestCase {
@@ -112,19 +112,44 @@ impl TestCase {
         Ok(all_events)
     }
 
-    fn take_watch_changes(&self) -> Vec<ChangeEvent> {
-        self.try_take_watch_changes(Duration::from_secs(10))
+    fn take_watch_changes<M: MatchEvent>(&self, matcher: M) -> Vec<ChangeEvent> {
+        self.try_take_watch_changes(matcher, Duration::from_secs(10))
             .expect("Expected watch changes but observed none")
     }
 
-    fn try_take_watch_changes(&self, timeout: Duration) -> Option<Vec<ChangeEvent>> {
-        let watcher = self.watcher.as_ref()?;
+    fn try_take_watch_changes<M: MatchEvent>(
+        &self,
+        mut matcher: M,
+        timeout: Duration,
+    ) -> Result<Vec<ChangeEvent>, Vec<ChangeEvent>> {
+        let watcher = self
+            .watcher
+            .as_ref()
+            .expect("Cannot call `try_take_watch_changes` after `stop_watch`");
 
-        let mut all_events = self
-            .changes_receiver
-            .recv_timeout(timeout)
-            .unwrap_or_default();
-        watcher.flush();
+        let start = Instant::now();
+        let mut all_events = Vec::new();
+
+        loop {
+            let events = self
+                .changes_receiver
+                .recv_timeout(Duration::from_millis(100))
+                .unwrap_or_default();
+
+            if events
+                .iter()
+                .any(|event| matcher.match_event(event) || event.is_rescan())
+            {
+                all_events.extend(events);
+                break;
+            }
+
+            all_events.extend(events);
+
+            if start.elapsed() > timeout {
+                return Err(all_events);
+            }
+        }
 
         while let Ok(event) = self
             .changes_receiver
@@ -134,26 +159,28 @@ impl TestCase {
             watcher.flush();
         }
 
-        if all_events.is_empty() {
-            return None;
-        }
-        Some(all_events)
+        Ok(all_events)
     }
 
     fn apply_changes(&mut self, changes: Vec<ChangeEvent>) {
-        self.db.apply_changes(changes, Some(&self.configuration));
+        self.db.apply_changes(changes, None);
     }
 
-    fn update_search_path_settings(
-        &mut self,
-        configuration: SearchPathConfiguration,
-    ) -> anyhow::Result<()> {
-        let program = Program::get(self.db());
+    fn update_options(&mut self, options: Options) -> anyhow::Result<()> {
+        std::fs::write(
+            self.project_path("pyproject.toml").as_std_path(),
+            toml::to_string(&PyProject {
+                project: None,
+                tool: Some(Tool {
+                    knot: Some(options),
+                }),
+            })
+            .context("Failed to serialize options")?,
+        )
+        .context("Failed to write configuration")?;
 
-        let new_settings = configuration.to_settings(self.db.project().root(&self.db));
-        self.configuration.search_paths = configuration;
-
-        program.update_search_paths(&mut self.db, &new_settings)?;
+        let changes = self.take_watch_changes(event_for_file("pyproject.toml"));
+        self.apply_changes(changes);
 
         if let Some(watcher) = &mut self.watcher {
             watcher.update(&self.db);
@@ -234,14 +261,13 @@ fn setup<F>(setup_files: F) -> anyhow::Result<TestCase>
 where
     F: SetupFiles,
 {
-    setup_with_search_paths(setup_files, |_root, _project_path| {
-        SearchPathConfiguration::default()
-    })
+    setup_with_options(setup_files, |_root, _project_path| None)
 }
 
-fn setup_with_search_paths<F>(
+// TODO: Replace with configuration?
+fn setup_with_options<F>(
     setup_files: F,
-    create_search_paths: impl FnOnce(&SystemPath, &SystemPath) -> SearchPathConfiguration,
+    create_options: impl FnOnce(&SystemPath, &SystemPath) -> Option<Options>,
 ) -> anyhow::Result<TestCase>
 where
     F: SetupFiles,
@@ -275,32 +301,33 @@ where
 
     let system = OsSystem::new(&project_path);
 
-    let search_paths = create_search_paths(&root_path, &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 {
+                project: None,
+                tool: Some(Tool {
+                    knot: Some(options),
+                }),
+            })
+            .context("Failed to serialize options")?,
+        )
+        .context("Failed to write configuration")?;
+    }
 
-    for path in search_paths
+    let project = ProjectMetadata::discover(&project_path, &system)?;
+    let program_settings = project.to_program_settings(&system);
+
+    for path in program_settings
+        .search_paths
         .extra_paths
         .iter()
-        .flatten()
-        .chain(search_paths.typeshed.iter())
-        .chain(search_paths.site_packages.iter().flat_map(|site_packages| {
-            if let SitePackages::Known(path) = site_packages {
-                path.as_slice()
-            } else {
-                &[]
-            }
-        }))
+        .chain(program_settings.search_paths.custom_typeshed.as_ref())
     {
         std::fs::create_dir_all(path.as_std_path())
             .with_context(|| format!("Failed to create search path `{path}`"))?;
     }
 
-    let configuration = Configuration {
-        python_version: Some(PythonVersion::PY312),
-        search_paths,
-    };
-
-    let project = ProjectMetadata::discover(&project_path, &system, Some(&configuration))?;
-
     let db = ProjectDatabase::new(project, system)?;
 
     let (sender, receiver) = crossbeam::channel::unbounded();
@@ -316,12 +343,12 @@ where
         watcher: Some(watcher),
         _temp_dir: temp_dir,
         root_dir: root_path,
-        configuration,
     };
 
     // Sometimes the file watcher reports changes for events that happened before the watcher was started.
     // Do a best effort at dropping these events.
-    test_case.try_take_watch_changes(Duration::from_millis(100));
+    let _ =
+        test_case.try_take_watch_changes(|_event: &ChangeEvent| true, Duration::from_millis(100));
 
     Ok(test_case)
 }
@@ -762,13 +789,15 @@ fn directory_deleted() -> anyhow::Result<()> {
 
 #[test]
 fn search_path() -> anyhow::Result<()> {
-    let mut case =
-        setup_with_search_paths([("bar.py", "import sub.a")], |root_path, _project_path| {
-            SearchPathConfiguration {
-                site_packages: Some(SitePackages::Known(vec![root_path.join("site_packages")])),
-                ..SearchPathConfiguration::default()
-            }
-        })?;
+    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(root_path.join("site_packages"))]),
+                ..EnvironmentOptions::default()
+            }),
+            ..Options::default()
+        })
+    })?;
 
     let site_packages = case.root_path().join("site_packages");
 
@@ -802,9 +831,12 @@ fn add_search_path() -> anyhow::Result<()> {
     assert!(resolve_module(case.db().upcast(), &ModuleName::new_static("a").unwrap()).is_none());
 
     // Register site-packages as a search path.
-    case.update_search_path_settings(SearchPathConfiguration {
-        site_packages: Some(SitePackages::Known(vec![site_packages.clone()])),
-        ..SearchPathConfiguration::default()
+    case.update_options(Options {
+        environment: Some(EnvironmentOptions {
+            extra_paths: Some(vec![RelativePathBuf::cli("site_packages")]),
+            ..EnvironmentOptions::default()
+        }),
+        ..Options::default()
     })
     .expect("Search path settings to be valid");
 
@@ -821,19 +853,22 @@ fn add_search_path() -> anyhow::Result<()> {
 
 #[test]
 fn remove_search_path() -> anyhow::Result<()> {
-    let mut case =
-        setup_with_search_paths([("bar.py", "import sub.a")], |root_path, _project_path| {
-            SearchPathConfiguration {
-                site_packages: Some(SitePackages::Known(vec![root_path.join("site_packages")])),
-                ..SearchPathConfiguration::default()
-            }
-        })?;
+    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(root_path.join("site_packages"))]),
+                ..EnvironmentOptions::default()
+            }),
+            ..Options::default()
+        })
+    })?;
 
     // Remove site packages from the search path settings.
     let site_packages = case.root_path().join("site_packages");
-    case.update_search_path_settings(SearchPathConfiguration {
-        site_packages: None,
-        ..SearchPathConfiguration::default()
+
+    case.update_options(Options {
+        environment: None,
+        ..Options::default()
     })
     .expect("Search path settings to be valid");
 
@@ -846,9 +881,67 @@ fn remove_search_path() -> anyhow::Result<()> {
     Ok(())
 }
 
+#[test]
+fn change_python_version_and_platform() -> anyhow::Result<()> {
+    let mut case = setup_with_options(
+        // `sys.last_exc` is a Python 3.12 only feature
+        // `os.getegid()` is Unix only
+        [(
+            "bar.py",
+            r#"
+import sys
+import os
+print(sys.last_exc, os.getegid())
+"#,
+        )],
+        |_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.")?;
+
+    assert_eq!(diagnostics.len(), 2);
+    assert_eq!(
+        diagnostics[0].message(),
+        "Type `<module 'sys'>` has no attribute `last_exc`"
+    );
+    assert_eq!(
+        diagnostics[1].message(),
+        "Type `<module 'os'>` has no attribute `getegid`"
+    );
+
+    // Change the python version
+    case.update_options(Options {
+        environment: Some(EnvironmentOptions {
+            python_version: Some(RangedValue::cli(PythonVersion::PY312)),
+            python_platform: Some(RangedValue::cli(PythonPlatform::Identifier(
+                "linux".to_string(),
+            ))),
+            ..EnvironmentOptions::default()
+        }),
+        ..Options::default()
+    })
+    .expect("Search path settings to be valid");
+
+    let diagnostics = case.db.check().context("Failed to check project.")?;
+    assert!(diagnostics.is_empty());
+
+    Ok(())
+}
+
 #[test]
 fn changed_versions_file() -> anyhow::Result<()> {
-    let mut case = setup_with_search_paths(
+    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())?;
@@ -860,9 +953,14 @@ fn changed_versions_file() -> anyhow::Result<()> {
 
             Ok(())
         },
-        |root_path, _project_path| SearchPathConfiguration {
-            typeshed: Some(root_path.join("typeshed")),
-            ..SearchPathConfiguration::default()
+        |root_path, _project_path| {
+            Some(Options {
+                environment: Some(EnvironmentOptions {
+                    typeshed: Some(RelativePathBuf::cli(root_path.join("typeshed"))),
+                    ..EnvironmentOptions::default()
+                }),
+                ..Options::default()
+            })
         },
     )?;
 
@@ -1127,7 +1225,7 @@ mod unix {
         update_file(baz_original, "def baz(): print('Version 2')")
             .context("Failed to update bar/baz.py")?;
 
-        let changes = case.take_watch_changes();
+        let changes = case.take_watch_changes(event_for_file("baz.py"));
 
         case.apply_changes(changes);
 
@@ -1259,7 +1357,7 @@ mod unix {
     /// ```
     #[test]
     fn symlinked_module_search_path() -> anyhow::Result<()> {
-        let mut case = setup_with_search_paths(
+        let mut case = setup_with_options(
             |root: &SystemPath, project: &SystemPath| {
                 // Set up the symlink target.
                 let site_packages = root.join("site-packages");
@@ -1282,11 +1380,17 @@ mod unix {
 
                 Ok(())
             },
-            |_root, project| SearchPathConfiguration {
-                site_packages: Some(SitePackages::Known(vec![
-                    project.join(".venv/lib/python3.12/site-packages")
-                ])),
-                ..SearchPathConfiguration::default()
+            |_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()
+                })
             },
         )?;
 

crates/red_knot_project/Cargo.toml

@@ -1,5 +1,5 @@
 [package]
-name = "red_knot_workspace"
+name = "red_knot_project"
 version = "0.0.0"
 edition.workspace = true
 rust-version.workspace = true
@@ -12,12 +12,12 @@ license.workspace = true
 # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
 
 [dependencies]
-red_knot_python_semantic = { workspace = true }
-
 ruff_cache = { workspace = true }
 ruff_db = { workspace = true, features = ["os", "cache", "serde"] }
+ruff_macros = { workspace = true }
 ruff_python_ast = { workspace = true, features = ["serde"] }
 ruff_text_size = { workspace = true }
+red_knot_python_semantic = { workspace = true, features = ["serde"] }
 red_knot_vendored = { workspace = true }
 
 anyhow = { workspace = true }
@@ -34,7 +34,6 @@ toml = { workspace = true }
 tracing = { workspace = true }
 
 [dev-dependencies]
-red_knot_python_semantic = { workspace = true, features = ["serde"] }
 ruff_db = { workspace = true, features = ["testing"] }
 glob = { workspace = true }
 insta = { workspace = true, features = ["redactions", "ron"] }