BDD

#14946 fixed our handling of nested imports with the `import` statement,
but didn't touch `from...import` statements.

cf
https://github.com/astral-sh/ruff/issues/14826#issuecomment-2525344515

.github/actionlint.yaml

@@ -0,0 +1,9 @@
+# Configuration for the actionlint tool, which we run via pre-commit
+# to verify the correctness of the syntax in our GitHub Actions workflows.
+
+self-hosted-runner:
+  # Various runners we use that aren't recognized out-of-the-box by actionlint:
+  labels:
+    - depot-ubuntu-latest-8
+    - depot-ubuntu-22.04-16
+    - windows-latest-xlarge

.github/workflows/build-binaries.yml

@@ -53,7 +53,7 @@ jobs:
           args: --out dist
       - name: "Test sdist"
         run: |
-          pip install dist/${PACKAGE_NAME}-*.tar.gz --force-reinstall
+          pip install dist/"${PACKAGE_NAME}"-*.tar.gz --force-reinstall
           "${MODULE_NAME}" --help
           python -m "${MODULE_NAME}" --help
       - name: "Upload sdist"
@@ -125,7 +125,7 @@ jobs:
           args: --release --locked --out dist
       - name: "Test wheel - aarch64"
         run: |
-          pip install dist/${PACKAGE_NAME}-*.whl --force-reinstall
+          pip install dist/"${PACKAGE_NAME}"-*.whl --force-reinstall
           ruff --help
           python -m ruff --help
       - name: "Upload wheels"
@@ -186,7 +186,7 @@ jobs:
         if: ${{ !startsWith(matrix.platform.target, 'aarch64') }}
         shell: bash
         run: |
-          python -m pip install dist/${PACKAGE_NAME}-*.whl --force-reinstall
+          python -m pip install dist/"${PACKAGE_NAME}"-*.whl --force-reinstall
           "${MODULE_NAME}" --help
           python -m "${MODULE_NAME}" --help
       - name: "Upload wheels"
@@ -236,7 +236,7 @@ jobs:
       - name: "Test wheel"
         if: ${{ startsWith(matrix.target, 'x86_64') }}
         run: |
-          pip install dist/${PACKAGE_NAME}-*.whl --force-reinstall
+          pip install dist/"${PACKAGE_NAME}"-*.whl --force-reinstall
           "${MODULE_NAME}" --help
           python -m "${MODULE_NAME}" --help
       - name: "Upload wheels"

.github/workflows/build-docker.yml

@@ -142,6 +142,7 @@ jobs:
         # The printf will expand the base image with the `<RUFF_BASE_IMG>@sha256:<sha256> ...` for each sha256 in the directory
         # The final command becomes `docker buildx imagetools create -t tag1 -t tag2 ... <RUFF_BASE_IMG>@sha256:<sha256_1> <RUFF_BASE_IMG>@sha256:<sha256_2> ...`
         run: |
+          # shellcheck disable=SC2046
           docker buildx imagetools create \
             $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \
             $(printf "${RUFF_BASE_IMG}@sha256:%s " *)
@@ -286,6 +287,8 @@ jobs:
         # The final command becomes `docker buildx imagetools create -t tag1 -t tag2 ... <RUFF_BASE_IMG>@sha256:<sha256_1> <RUFF_BASE_IMG>@sha256:<sha256_2> ...`
         run: |
           readarray -t lines <<< "$DOCKER_METADATA_OUTPUT_ANNOTATIONS"; annotations=(); for line in "${lines[@]}"; do annotations+=(--annotation "$line"); done
+
+          # shellcheck disable=SC2046
           docker buildx imagetools create \
             "${annotations[@]}" \
             $(jq -cr '.tags | map("-t " + .) | join(" ")' <<< "$DOCKER_METADATA_OUTPUT_JSON") \

.github/workflows/ci.yaml

@@ -290,7 +290,9 @@ jobs:
           file: "Cargo.toml"
           field: "workspace.package.rust-version"
       - name: "Install Rust toolchain"
-        run: rustup default ${{ steps.msrv.outputs.value }}
+        env:
+          MSRV: ${{ steps.msrv.outputs.value }}
+        run: rustup default "${MSRV}"
       - name: "Install mold"
         uses: rui314/setup-mold@v1
       - name: "Install cargo nextest"
@@ -306,7 +308,8 @@ jobs:
         shell: bash
         env:
           NEXTEST_PROFILE: "ci"
-        run: cargo +${{ steps.msrv.outputs.value }} insta test --all-features --unreferenced reject --test-runner nextest
+          MSRV: ${{ steps.msrv.outputs.value }}
+        run: cargo "+${MSRV}" insta test --all-features --unreferenced reject --test-runner nextest
 
   cargo-fuzz-build:
     name: "cargo fuzz build"
@@ -354,16 +357,18 @@ jobs:
           name: ruff
           path: ruff-to-test
       - name: Fuzz
+        env:
+          DOWNLOAD_PATH: ${{ steps.download-cached-binary.outputs.download-path }}
         run: |
           # Make executable, since artifact download doesn't preserve this
-          chmod +x ${{ steps.download-cached-binary.outputs.download-path }}/ruff
+          chmod +x "${DOWNLOAD_PATH}/ruff"
 
           (
             uvx \
-            --python=${{ env.PYTHON_VERSION }} \
+            --python="${PYTHON_VERSION}" \
             --from=./python/py-fuzzer \
             fuzz \
-            --test-executable=${{ steps.download-cached-binary.outputs.download-path }}/ruff \
+            --test-executable="${DOWNLOAD_PATH}/ruff" \
             --bin=ruff \
             0-500
           )
@@ -429,64 +434,72 @@ jobs:
 
       - name: Run `ruff check` stable ecosystem check
         if: ${{ needs.determine_changes.outputs.linter == 'true' }}
+        env:
+          DOWNLOAD_PATH: ${{ steps.ruff-target.outputs.download-path }}
         run: |
           # Make executable, since artifact download doesn't preserve this
-          chmod +x ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff
+          chmod +x ./ruff "${DOWNLOAD_PATH}/ruff"
 
           # Set pipefail to avoid hiding errors with tee
           set -eo pipefail
 
-          ruff-ecosystem check ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff --cache ./checkouts --output-format markdown | tee ecosystem-result-check-stable
+          ruff-ecosystem check ./ruff "${DOWNLOAD_PATH}/ruff" --cache ./checkouts --output-format markdown | tee ecosystem-result-check-stable
 
-          cat ecosystem-result-check-stable > $GITHUB_STEP_SUMMARY
+          cat ecosystem-result-check-stable > "$GITHUB_STEP_SUMMARY"
           echo "### Linter (stable)"  > ecosystem-result
           cat ecosystem-result-check-stable >> ecosystem-result
           echo "" >> ecosystem-result
 
       - name: Run `ruff check` preview ecosystem check
         if: ${{ needs.determine_changes.outputs.linter == 'true' }}
+        env:
+          DOWNLOAD_PATH: ${{ steps.ruff-target.outputs.download-path }}
         run: |
           # Make executable, since artifact download doesn't preserve this
-          chmod +x ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff
+          chmod +x ./ruff "${DOWNLOAD_PATH}/ruff"
 
           # Set pipefail to avoid hiding errors with tee
           set -eo pipefail
 
-          ruff-ecosystem check ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff --cache ./checkouts --output-format markdown --force-preview | tee ecosystem-result-check-preview
+          ruff-ecosystem check ./ruff "${DOWNLOAD_PATH}/ruff" --cache ./checkouts --output-format markdown --force-preview | tee ecosystem-result-check-preview
 
-          cat ecosystem-result-check-preview > $GITHUB_STEP_SUMMARY
+          cat ecosystem-result-check-preview > "$GITHUB_STEP_SUMMARY"
           echo "### Linter (preview)" >> ecosystem-result
           cat ecosystem-result-check-preview >> ecosystem-result
           echo "" >> ecosystem-result
 
       - name: Run `ruff format` stable ecosystem check
         if: ${{ needs.determine_changes.outputs.formatter == 'true' }}
+        env:
+          DOWNLOAD_PATH: ${{ steps.ruff-target.outputs.download-path }}
         run: |
           # Make executable, since artifact download doesn't preserve this
-          chmod +x ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff
+          chmod +x ./ruff "${DOWNLOAD_PATH}/ruff"
 
           # Set pipefail to avoid hiding errors with tee
           set -eo pipefail
 
-          ruff-ecosystem format ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff --cache ./checkouts --output-format markdown | tee ecosystem-result-format-stable
+          ruff-ecosystem format ./ruff "${DOWNLOAD_PATH}/ruff" --cache ./checkouts --output-format markdown | tee ecosystem-result-format-stable
 
-          cat ecosystem-result-format-stable > $GITHUB_STEP_SUMMARY
+          cat ecosystem-result-format-stable > "$GITHUB_STEP_SUMMARY"
           echo "### Formatter (stable)" >> ecosystem-result
           cat ecosystem-result-format-stable >> ecosystem-result
           echo "" >> ecosystem-result
 
       - name: Run `ruff format` preview ecosystem check
         if: ${{ needs.determine_changes.outputs.formatter == 'true' }}
+        env:
+          DOWNLOAD_PATH: ${{ steps.ruff-target.outputs.download-path }}
         run: |
           # Make executable, since artifact download doesn't preserve this
-          chmod +x ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff
+          chmod +x ./ruff "${DOWNLOAD_PATH}/ruff"
 
           # Set pipefail to avoid hiding errors with tee
           set -eo pipefail
 
-          ruff-ecosystem format ./ruff ${{ steps.ruff-target.outputs.download-path }}/ruff --cache ./checkouts --output-format markdown --force-preview | tee ecosystem-result-format-preview
+          ruff-ecosystem format ./ruff "${DOWNLOAD_PATH}/ruff" --cache ./checkouts --output-format markdown --force-preview | tee ecosystem-result-format-preview
 
-          cat ecosystem-result-format-preview > $GITHUB_STEP_SUMMARY
+          cat ecosystem-result-format-preview > "$GITHUB_STEP_SUMMARY"
           echo "### Formatter (preview)" >> ecosystem-result
           cat ecosystem-result-format-preview >> ecosystem-result
           echo "" >> ecosystem-result
@@ -541,7 +554,7 @@ jobs:
           args: --out dist
       - name: "Test wheel"
         run: |
-          pip install --force-reinstall --find-links dist ${{ env.PACKAGE_NAME }}
+          pip install --force-reinstall --find-links dist "${PACKAGE_NAME}"
           ruff --help
           python -m ruff --help
       - name: "Remove wheels from cache"
@@ -570,13 +583,13 @@ jobs:
           key: pre-commit-${{ hashFiles('.pre-commit-config.yaml') }}
       - name: "Run pre-commit"
         run: |
-          echo '```console' > $GITHUB_STEP_SUMMARY
+          echo '```console' > "$GITHUB_STEP_SUMMARY"
           # Enable color output for pre-commit and remove it for the summary
           SKIP=cargo-fmt,clippy,dev-generate-all pre-commit run --all-files --show-diff-on-failure --color=always | \
-            tee >(sed -E 's/\x1B\[([0-9]{1,2}(;[0-9]{1,2})*)?[mGK]//g' >> $GITHUB_STEP_SUMMARY) >&1
-          exit_code=${PIPESTATUS[0]}
-          echo '```' >> $GITHUB_STEP_SUMMARY
-          exit $exit_code
+            tee >(sed -E 's/\x1B\[([0-9]{1,2}(;[0-9]{1,2})*)?[mGK]//g' >> "$GITHUB_STEP_SUMMARY") >&1
+          exit_code="${PIPESTATUS[0]}"
+          echo '```' >> "$GITHUB_STEP_SUMMARY"
+          exit "$exit_code"
 
   docs:
     name: "mkdocs"
@@ -637,7 +650,7 @@ jobs:
       - name: "Run checks"
         run: scripts/formatter_ecosystem_checks.sh
       - name: "Github step summary"
-        run: cat target/formatter-ecosystem/stats.txt > $GITHUB_STEP_SUMMARY
+        run: cat target/formatter-ecosystem/stats.txt > "$GITHUB_STEP_SUMMARY"
       - name: "Remove checkouts from cache"
         run: rm -r target/formatter-ecosystem
 
@@ -676,11 +689,13 @@ jobs:
           just install
 
       - name: Run ruff-lsp tests
+        env:
+          DOWNLOAD_PATH: ${{ steps.ruff-target.outputs.download-path }}
         run: |
           # Setup development binary
           pip uninstall --yes ruff
-          chmod +x ${{ steps.ruff-target.outputs.download-path }}/ruff
-          export PATH=${{ steps.ruff-target.outputs.download-path }}:$PATH
+          chmod +x "${DOWNLOAD_PATH}/ruff"
+          export PATH="${DOWNLOAD_PATH}:${PATH}"
           ruff version
 
           just test

.github/workflows/daily_fuzz.yaml

@@ -46,6 +46,7 @@ jobs:
         run: cargo build --locked
       - name: Fuzz
         run: |
+          # shellcheck disable=SC2046
           (
             uvx \
             --python=3.12 \

.github/workflows/pr-comment.yaml

@@ -10,12 +10,11 @@ on:
         description: The ecosystem workflow that triggers the workflow run
         required: true
 
-permissions:
-  pull-requests: write
-
 jobs:
   comment:
     runs-on: ubuntu-latest
+    permissions:
+      pull-requests: write
     steps:
       - uses: dawidd6/action-download-artifact@v7
         name: Download pull request number
@@ -30,7 +29,7 @@ jobs:
         run: |
           if [[ -f pr-number ]]
           then
-            echo "pr-number=$(<pr-number)" >> $GITHUB_OUTPUT
+            echo "pr-number=$(<pr-number)" >> "$GITHUB_OUTPUT"
           fi
 
       - uses: dawidd6/action-download-artifact@v7
@@ -66,9 +65,9 @@ jobs:
           cat pr/ecosystem/ecosystem-result >> comment.txt
           echo "" >> comment.txt
 
-          echo 'comment<<EOF' >> $GITHUB_OUTPUT
-          cat comment.txt >> $GITHUB_OUTPUT
-          echo 'EOF' >> $GITHUB_OUTPUT
+          echo 'comment<<EOF' >> "$GITHUB_OUTPUT"
+          cat comment.txt >> "$GITHUB_OUTPUT"
+          echo 'EOF' >> "$GITHUB_OUTPUT"
 
       - name: Find existing comment
         uses: peter-evans/find-comment@v3

.github/workflows/publish-docs.yml

@@ -44,8 +44,8 @@ jobs:
           # Use version as display name for now
           display_name="$version"
 
-          echo "version=$version" >> $GITHUB_ENV
-          echo "display_name=$display_name" >> $GITHUB_ENV
+          echo "version=$version" >> "$GITHUB_ENV"
+          echo "display_name=$display_name" >> "$GITHUB_ENV"
 
       - name: "Set branch name"
         run: |
@@ -55,8 +55,8 @@ jobs:
           # characters disallowed in git branch names with hyphens
           branch_display_name="$(echo "${display_name}" | tr -c '[:alnum:]._' '-' | tr -s '-')"
 
-          echo "branch_name=update-docs-$branch_display_name-$timestamp" >> $GITHUB_ENV
-          echo "timestamp=$timestamp" >> $GITHUB_ENV
+          echo "branch_name=update-docs-$branch_display_name-$timestamp" >> "$GITHUB_ENV"
+          echo "timestamp=$timestamp" >> "$GITHUB_ENV"
 
       - name: "Add SSH key"
         if: ${{ env.MKDOCS_INSIDERS_SSH_KEY_EXISTS == 'true' }}
@@ -112,7 +112,7 @@ jobs:
           GITHUB_TOKEN: ${{ secrets.ASTRAL_DOCS_PAT }}
         run: |
           # set the PR title
-          pull_request_title="Update ruff documentation for "${display_name}""
+          pull_request_title="Update ruff documentation for ${display_name}"
 
           # Delete any existing pull requests that are open for this version
           # by checking against pull_request_title because the new PR will
@@ -124,10 +124,12 @@ jobs:
           git push origin "${branch_name}"
 
           # create the PR
-          gh pr create --base main --head "${branch_name}" \
-            --title "$pull_request_title" \
-            --body "Automated documentation update for "${display_name}"" \
-            --label "documentation"
+          gh pr create \
+            --base=main \
+            --head="${branch_name}" \
+            --title="${pull_request_title}" \
+            --body="Automated documentation update for ${display_name}" \
+            --label="documentation"
 
       - name: "Merge Pull Request"
         if: ${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}

.github/workflows/sync_typeshed.yaml

@@ -59,7 +59,7 @@ jobs:
         run: |
           cd ruff
           git push --force origin typeshedbot/sync-typeshed
-          gh pr list --repo $GITHUB_REPOSITORY --head typeshedbot/sync-typeshed --json id --jq length | grep 1 && exit 0 # exit if there is existing pr
+          gh pr list --repo "$GITHUB_REPOSITORY" --head typeshedbot/sync-typeshed --json id --jq length | grep 1 && exit 0 # exit if there is existing pr
           gh pr create --title "Sync vendored typeshed stubs" --body "Close and reopen this PR to trigger CI" --label "internal"
 
   create-issue-on-failure:

.github/zizmor.yml

@@ -0,0 +1,6 @@
+# Configuration for the zizmor static analysis tool, run via pre-commit in CI
+# https://woodruffw.github.io/zizmor/configuration/
+rules:
+  dangerous-triggers:
+    ignore:
+      - pr-comment.yaml

.markdownlint.yaml

@@ -21,3 +21,11 @@ MD014: false
 MD024:
   # Allow when nested under different parents e.g. CHANGELOG.md
   siblings_only: true
+
+# MD046/code-block-style
+#
+# Ignore this because it conflicts with the code block style used in content
+# tabs of mkdocs-material which is to add a blank line after the content title.
+#
+# Ref: https://github.com/astral-sh/ruff/pull/15011#issuecomment-2544790854
+MD046: false

.pre-commit-config.yaml

@@ -26,9 +26,8 @@ repos:
     hooks:
       - id: mdformat
         additional_dependencies:
-          - mdformat-mkdocs
-          - mdformat-admon
-          - mdformat-footnote
+          - mdformat-mkdocs==4.0.0
+          - mdformat-footnote==0.1.1
         exclude: |
           (?x)^(
             docs/formatter/black\.md
@@ -59,7 +58,7 @@ repos:
           - black==24.10.0
 
   - repo: https://github.com/crate-ci/typos
-    rev: v1.28.2
+    rev: v1.28.3
     hooks:
       - id: typos
 
@@ -73,7 +72,7 @@ repos:
         pass_filenames: false # This makes it a lot faster
 
   - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.8.2
+    rev: v0.8.3
     hooks:
       - id: ruff-format
       - id: ruff
@@ -88,8 +87,10 @@ repos:
       - id: prettier
         types: [yaml]
 
+  # 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: v0.8.0
+    rev: v0.9.2
     hooks:
       - id: zizmor
         # `release.yml` is autogenerated by `dist`; security issues need to be fixed there
@@ -101,5 +102,23 @@ repos:
     hooks:
       - id: check-github-workflows
 
+  # `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: v1.7.4
+    hooks:
+      - id: actionlint
+        # `release.yml` is autogenerated by `dist`; issues need to be fixed there
+        # (https://opensource.axo.dev/cargo-dist/)
+        exclude: .github/workflows/release.yml
+        args:
+          - "-ignore=SC2129" # ignorable stylistic lint from shellcheck
+          - "-ignore=SC2016" # another shellcheck lint: seems to have false positives?
+        additional_dependencies:
+          # actionlint has a shellcheck integration which extracts shell scripts in `run:` steps from GitHub Actions
+          # and checks these with shellcheck. This is arguably its most useful feature,
+          # but the integration only works if shellcheck is installed
+          - "github.com/wasilibs/go-shellcheck/cmd/shellcheck@v0.10.0"
+
 ci:
   skip: [cargo-fmt, dev-generate-all]

Cargo.lock

@@ -30,6 +30,12 @@ dependencies = [
  "memchr",
 ]
 
+[[package]]
+name = "allocator-api2"
+version = "0.2.21"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "683d7910e743518b0e34f1186f92494becacb047c7b6bf616c96772180fef923"
+
 [[package]]
 name = "android-tzdata"
 version = "0.1.1"
@@ -203,6 +209,18 @@ version = "2.6.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b048fb63fd8b5923fc5aa7b340d8e156aec7ec02f0c78fa8a6ddc2613f6f71de"
 
+[[package]]
+name = "bitvec"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "1bc2832c24239b0141d5674bb9174f9d68a8b5b3f2753311927c172ca46f7e9c"
+dependencies = [
+ "funty",
+ "radium",
+ "tap",
+ "wyz",
+]
+
 [[package]]
 name = "block-buffer"
 version = "0.10.4"
@@ -220,9 +238,9 @@ checksum = "7f839cdf7e2d3198ac6ca003fd8ebc61715755f41c1cad15ff13df67531e00ed"
 
 [[package]]
 name = "bstr"
-version = "1.11.0"
+version = "1.11.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "1a68f1f47cdf0ec8ee4b941b2eee2a80cb796db73118c0dd09ac63fbe405be22"
+checksum = "786a307d683a5bf92e6fd5fd69a7eb613751668d1d8d67d802846dfe367c62c8"
 dependencies = [
  "memchr",
  "regex-automata 0.4.8",
@@ -314,9 +332,9 @@ dependencies = [
 
 [[package]]
 name = "chrono"
-version = "0.4.38"
+version = "0.4.39"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "a21f936df1771bf62b77f047b726c4625ff2e8aa607c01ec06e5a05bd8463401"
+checksum = "7e36cc9d416881d2e24f9a963be5fb1cd90966419ac844274161d10488b3e825"
 dependencies = [
  "android-tzdata",
  "iana-time-zone",
@@ -465,12 +483,12 @@ checksum = "acbf1af155f9b9ef647e42cdc158db4b64a1b61f743629225fde6f3e0be2a7c7"
 
 [[package]]
 name = "colored"
-version = "2.1.0"
+version = "2.2.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "cbf2150cce219b664a8a70df7a1f933836724b503f8a413af9365b4dcc4d90b8"
+checksum = "117725a109d387c937a1533ce01b450cbde6b88abceea8473c4d7a85853cda3c"
 dependencies = [
  "lazy_static",
- "windows-sys 0.48.0",
+ "windows-sys 0.52.0",
 ]
 
 [[package]]
@@ -835,6 +853,15 @@ version = "0.3.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "fea41bba32d969b513997752735605054bc0dfa92b4c56bf1189f2e174be7a10"
 
+[[package]]
+name = "document-features"
+version = "0.2.10"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "cb6969eaabd2421f8a2775cfd2471a2b634372b4a25d41e3bd647b79912850a0"
+dependencies = [
+ "litrs",
+]
+
 [[package]]
 name = "drop_bomb"
 version = "0.1.5"
@@ -923,9 +950,9 @@ checksum = "e8c02a5121d4ea3eb16a80748c74f5549a5665e4c21333c6098f283870fbdea6"
 
 [[package]]
 name = "fern"
-version = "0.7.0"
+version = "0.7.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "69ff9c9d5fb3e6da8ac2f77ab76fe7e8087d512ce095200f8f29ac5b656cf6dc"
+checksum = "4316185f709b23713e41e3195f90edef7fb00c3ed4adc79769cf09cc762a3b29"
 dependencies = [
  "log",
 ]
@@ -952,6 +979,15 @@ dependencies = [
  "miniz_oxide",
 ]
 
+[[package]]
+name = "flume"
+version = "0.11.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da0e4dd2a88388a1f4ccc7c9ce104604dab68d9f408dc34cd45823d5a9069095"
+dependencies = [
+ "spin",
+]
+
 [[package]]
 name = "fnv"
 version = "1.0.7"
@@ -985,6 +1021,12 @@ dependencies = [
  "libc",
 ]
 
+[[package]]
+name = "funty"
+version = "2.0.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e6d5a32815ae3f33302d95fdcb2ce17862f8c65363dcfd29360480ba1001fc9c"
+
 [[package]]
 name = "generic-array"
 version = "0.14.7"
@@ -1102,6 +1144,17 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "hugealloc"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "542733215a252c27c674e5d875a910d7de509cb74123d0bdbaa050f871ec84c2"
+dependencies = [
+ "allocator-api2",
+ "libc",
+ "sptr",
+]
+
 [[package]]
 name = "humantime"
 version = "2.1.0"
@@ -1444,6 +1497,12 @@ dependencies = [
  "once_cell",
 ]
 
+[[package]]
+name = "is_sorted"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "357376465c37db3372ef6a00585d336ed3d0f11d4345eef77ebcb05865392b21"
+
 [[package]]
 name = "itertools"
 version = "0.10.5"
@@ -1521,9 +1580,9 @@ checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
 [[package]]
 name = "libc"
-version = "0.2.167"
+version = "0.2.168"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "09d6582e104315a817dff97f75133544b2e094ee22447d2acf4a74e189ba06fc"
+checksum = "5aaeb2981e0606ca11d79718f8bb01164f1d6ed75080182d3abf017e6d244b6d"
 
 [[package]]
 name = "libcst"
@@ -1571,6 +1630,12 @@ dependencies = [
  "redox_syscall 0.5.3",
 ]
 
+[[package]]
+name = "linear-hashtbl"
+version = "0.1.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e252bb7e9b36739fb2482438638e862241d111c76fae3ebee272454477c63a4f"
+
 [[package]]
 name = "linked-hash-map"
 version = "0.5.6"
@@ -1589,6 +1654,12 @@ version = "0.7.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "643cb0b8d4fcc284004d5fd0d67ccf61dfffadb7f75e1e71bc420f4688a3a704"
 
+[[package]]
+name = "litrs"
+version = "0.4.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b4ce301924b7887e9d637144fdade93f9dfff9b60981d4ac161db09720d39aa5"
+
 [[package]]
 name = "lock_api"
 version = "0.4.11"
@@ -1703,6 +1774,12 @@ dependencies = [
  "windows-sys 0.52.0",
 ]
 
+[[package]]
+name = "nanorand"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "6a51313c5820b0b02bd422f4b44776fbf47961755c74ce64afc73bfad10226c3"
+
 [[package]]
 name = "natord"
 version = "1.0.9"
@@ -1856,6 +1933,153 @@ version = "0.1.1"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "b15813163c1d831bf4a13c3610c05c0d03b39feb07f7e09fa234dac9b15aaf39"
 
+[[package]]
+name = "oxidd"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "22f7c2dbbc26b8d2e1ae861401a4bfa1d2e229e39da77ff8f0d64f2b4793e6da"
+dependencies = [
+ "cfg-if",
+ "document-features",
+ "oxidd-cache",
+ "oxidd-core",
+ "oxidd-derive",
+ "oxidd-dump",
+ "oxidd-manager-index",
+ "oxidd-reorder",
+ "oxidd-rules-bdd",
+ "oxidd-rules-mtbdd",
+ "oxidd-rules-tdd",
+ "oxidd-rules-zbdd",
+ "rustc-hash 1.1.0",
+]
+
+[[package]]
+name = "oxidd-cache"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "efcc7923864f2a2525e76e26a3645b65a82e29ac3d3118d6906bad0117eb704e"
+dependencies = [
+ "allocator-api2",
+ "document-features",
+ "hugealloc",
+ "oxidd-core",
+ "parking_lot",
+]
+
+[[package]]
+name = "oxidd-core"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "b47e2c527b7aba7a7c789c7e5300df5a338002b33284c823fd08e1c661d176d6"
+dependencies = [
+ "nanorand",
+]
+
+[[package]]
+name = "oxidd-derive"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "4ccd72606db214bdf9b3880a6dedb50990fafdac23a05b65f982b65ac22862ac"
+dependencies = [
+ "proc-macro-error",
+ "proc-macro2",
+ "quote",
+ "syn 2.0.90",
+]
+
+[[package]]
+name = "oxidd-dump"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "84ef9fed6a604b8199c988efce9231de372b058cf9501d1b60fa53ed0ea1d43a"
+dependencies = [
+ "bitvec",
+ "document-features",
+ "is_sorted",
+ "memchr",
+ "oxidd-core",
+ "rustc-hash 1.1.0",
+]
+
+[[package]]
+name = "oxidd-manager-index"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dd41278c0cd6f0418f78e8ed5a3a062fa31449a929b3a0d03d4c1056af620cdc"
+dependencies = [
+ "bitvec",
+ "crossbeam-utils",
+ "linear-hashtbl",
+ "oxidd-core",
+ "parking_lot",
+ "rayon",
+ "rustc-hash 1.1.0",
+]
+
+[[package]]
+name = "oxidd-reorder"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "222b3b3c71f9c4a5f875c01fda840e25d40d4fa86a5f0636938c17f7adf6c068"
+dependencies = [
+ "flume",
+ "is_sorted",
+ "oxidd-core",
+ "rayon",
+ "smallvec",
+]
+
+[[package]]
+name = "oxidd-rules-bdd"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f8ab7d000b0fb53ddcc282296929f51b2a5215591f6c6aa134a9fca9f133f61b"
+dependencies = [
+ "bitvec",
+ "document-features",
+ "oxidd-core",
+ "oxidd-derive",
+ "oxidd-dump",
+]
+
+[[package]]
+name = "oxidd-rules-mtbdd"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "f9bd51a1a297d98cefd4843cf065aba5cb04b2e78b0623857f0f8babe9f3d421"
+dependencies = [
+ "document-features",
+ "oxidd-core",
+ "oxidd-derive",
+ "oxidd-dump",
+]
+
+[[package]]
+name = "oxidd-rules-tdd"
+version = "0.4.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "753f378e1d76f1f23afd1a06bbe4f23025ac95d19fb3c2b3ff052c0d3fcd9af3"
+dependencies = [
+ "document-features",
+ "oxidd-core",
+ "oxidd-derive",
+ "oxidd-dump",
+]
+
+[[package]]
+name = "oxidd-rules-zbdd"
+version = "0.9.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "821482c23511e87b1a9bd7f0454971f4a73b01a7ed16611179d79c5872690dce"
+dependencies = [
+ "bitvec",
+ "document-features",
+ "oxidd-core",
+ "oxidd-derive",
+ "oxidd-dump",
+]
+
 [[package]]
 name = "parking_lot"
 version = "0.12.3"
@@ -2127,6 +2351,29 @@ dependencies = [
  "yansi",
 ]
 
+[[package]]
+name = "proc-macro-error"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "da25490ff9892aab3fcf7c36f08cfb902dd3e71ca0f9f9517bea02a73a5ce38c"
+dependencies = [
+ "proc-macro-error-attr",
+ "proc-macro2",
+ "quote",
+ "version_check",
+]
+
+[[package]]
+name = "proc-macro-error-attr"
+version = "1.0.4"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "a1be40180e52ecc98ad80b184934baf3d0d29f979574e439af5a55274b35f869"
+dependencies = [
+ "proc-macro2",
+ "quote",
+ "version_check",
+]
+
 [[package]]
 name = "proc-macro2"
 version = "1.0.92"
@@ -2161,7 +2408,7 @@ dependencies = [
  "newtype-uuid",
  "quick-xml",
  "strip-ansi-escapes",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "uuid",
 ]
 
@@ -2203,6 +2450,12 @@ dependencies = [
  "proc-macro2",
 ]
 
+[[package]]
+name = "radium"
+version = "0.7.0"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "dc33ff2d4973d518d823d61aa239014831e521c75da58e3df4840d3f47749d09"
+
 [[package]]
 name = "rand"
 version = "0.8.5"
@@ -2265,6 +2518,9 @@ dependencies = [
  "crossbeam",
  "ctrlc",
  "filetime",
+ "oxidd",
+ "oxidd-core",
+ "oxidd-dump",
  "rayon",
  "red_knot_python_semantic",
  "red_knot_server",
@@ -2314,7 +2570,7 @@ dependencies = [
  "static_assertions",
  "tempfile",
  "test-case",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "tracing",
 ]
 
@@ -2411,7 +2667,7 @@ dependencies = [
  "rustc-hash 2.1.0",
  "salsa",
  "serde",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "toml",
  "tracing",
 ]
@@ -2564,7 +2820,7 @@ dependencies = [
  "strum",
  "tempfile",
  "test-case",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "tikv-jemallocator",
  "toml",
  "tracing",
@@ -2634,7 +2890,7 @@ dependencies = [
  "salsa",
  "serde",
  "tempfile",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "tracing",
  "tracing-subscriber",
  "tracing-tree",
@@ -2786,7 +3042,7 @@ dependencies = [
  "strum",
  "strum_macros",
  "test-case",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "toml",
  "typed-arena",
  "unicode-normalization",
@@ -2820,7 +3076,7 @@ dependencies = [
  "serde_json",
  "serde_with",
  "test-case",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "uuid",
 ]
 
@@ -2892,7 +3148,7 @@ dependencies = [
  "similar",
  "smallvec",
  "static_assertions",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "tracing",
 ]
 
@@ -3025,7 +3281,7 @@ dependencies = [
  "serde",
  "serde_json",
  "shellexpand",
- "thiserror 2.0.6",
+ "thiserror 2.0.7",
  "tracing",
  "tracing-subscriber",
 ]
@@ -3193,7 +3449,7 @@ checksum = "e86697c916019a8588c99b5fac3cead74ec0b4b819707a682fd4d23fa0ce1ba1"
 [[package]]
 name = "salsa"
 version = "0.18.0"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=254c749b02cde2fd29852a7463a33e800b771758#254c749b02cde2fd29852a7463a33e800b771758"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=3c7f1694c9efba751dbeeacfbc93b227586e316a#3c7f1694c9efba751dbeeacfbc93b227586e316a"
 dependencies = [
  "append-only-vec",
  "arc-swap",
@@ -3203,6 +3459,7 @@ dependencies = [
  "indexmap",
  "lazy_static",
  "parking_lot",
+ "rayon",
  "rustc-hash 2.1.0",
  "salsa-macro-rules",
  "salsa-macros",
@@ -3213,12 +3470,12 @@ dependencies = [
 [[package]]
 name = "salsa-macro-rules"
 version = "0.1.0"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=254c749b02cde2fd29852a7463a33e800b771758#254c749b02cde2fd29852a7463a33e800b771758"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=3c7f1694c9efba751dbeeacfbc93b227586e316a#3c7f1694c9efba751dbeeacfbc93b227586e316a"
 
 [[package]]
 name = "salsa-macros"
 version = "0.18.0"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=254c749b02cde2fd29852a7463a33e800b771758#254c749b02cde2fd29852a7463a33e800b771758"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=3c7f1694c9efba751dbeeacfbc93b227586e316a#3c7f1694c9efba751dbeeacfbc93b227586e316a"
 dependencies = [
  "heck",
  "proc-macro2",
@@ -3280,9 +3537,9 @@ checksum = "1c107b6f4780854c8b126e228ea8869f4d7b71260f962fefb57b996b8959ba6b"
 
 [[package]]
 name = "serde"
-version = "1.0.215"
+version = "1.0.216"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "6513c1ad0b11a9376da888e3e0baa0077f1aed55c17f50e7b2397136129fb88f"
+checksum = "0b9781016e935a97e8beecf0c933758c97a5520d32930e460142b4cd80c6338e"
 dependencies = [
  "serde_derive",
 ]
@@ -3300,9 +3557,9 @@ dependencies = [
 
 [[package]]
 name = "serde_derive"
-version = "1.0.215"
+version = "1.0.216"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "ad1e866f866923f252f05c889987993144fb74e722403468a4ebd70c3cd756c0"
+checksum = "46f859dbbf73865c6627ed570e78961cd3ac92407a2d117204c49232485da55e"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -3442,6 +3699,15 @@ name = "spin"
 version = "0.9.8"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "6980e8d7511241f8acf4aebddbb1ff938df5eebe98691418c4468d0b72a96a67"
+dependencies = [
+ "lock_api",
+]
+
+[[package]]
+name = "sptr"
+version = "0.3.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "3b9b39299b249ad65f3b7e96443bad61c02ca5cd3589f46cb6d610a0fd6c0d6a"
 
 [[package]]
 name = "stable_deref_trait"
@@ -3537,6 +3803,12 @@ dependencies = [
  "syn 2.0.90",
 ]
 
+[[package]]
+name = "tap"
+version = "1.0.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "55937e1799185b12863d447f42597ed69d9928686b8d88a1df17376a097d8369"
+
 [[package]]
 name = "tempfile"
 version = "3.14.0"
@@ -3623,11 +3895,11 @@ dependencies = [
 
 [[package]]
 name = "thiserror"
-version = "2.0.6"
+version = "2.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "8fec2a1820ebd077e2b90c4df007bebf344cd394098a13c563957d0afc83ea47"
+checksum = "93605438cbd668185516ab499d589afb7ee1859ea3d5fc8f6b0755e1c7443767"
 dependencies = [
- "thiserror-impl 2.0.6",
+ "thiserror-impl 2.0.7",
 ]
 
 [[package]]
@@ -3643,9 +3915,9 @@ dependencies = [
 
 [[package]]
 name = "thiserror-impl"
-version = "2.0.6"
+version = "2.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d65750cab40f4ff1929fb1ba509e9914eb756131cef4210da8d5d700d26f6312"
+checksum = "e1d8749b4531af2117677a5fcd12b1348a3fe2b81e36e61ffeac5c4aa3273e36"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4473,6 +4745,15 @@ version = "0.5.5"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1e9df38ee2d2c3c5948ea468a8406ff0db0b29ae1ffde1bcf20ef305bcc95c51"
 
+[[package]]
+name = "wyz"
+version = "0.5.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "05f360fc0b24296329c78fda852a1e9ae82de9cf7b27dae4b7f62f118f77b9ed"
+dependencies = [
+ "tap",
+]
+
 [[package]]
 name = "yansi"
 version = "1.0.1"

Cargo.toml

@@ -105,6 +105,7 @@ mimalloc = { version = "0.1.39" }
 natord = { version = "1.0.9" }
 notify = { version = "7.0.0" }
 ordermap = { version = "0.5.0" }
+oxidd = { version = "0.9.0", features = ["tdd"] }
 path-absolutize = { version = "3.1.1" }
 path-slash = { version = "0.2.1" }
 pathdiff = { version = "0.2.1" }
@@ -118,7 +119,8 @@ rand = { version = "0.8.5" }
 rayon = { version = "1.10.0" }
 regex = { version = "1.10.2" }
 rustc-hash = { version = "2.0.0" }
-salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "254c749b02cde2fd29852a7463a33e800b771758" }
+# When updating salsa, make sure to also update the revision in `fuzz/Cargo.toml`
+salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "3c7f1694c9efba751dbeeacfbc93b227586e316a" }
 schemars = { version = "0.8.16" }
 seahash = { version = "4.1.0" }
 serde = { version = "1.0.197", features = ["derive"] }

crates/red_knot/Cargo.toml

@@ -24,6 +24,9 @@ colored = { workspace = true }
 countme = { workspace = true, features = ["enable"] }
 crossbeam = { workspace = true }
 ctrlc = { version = "3.4.4" }
+oxidd = { workspace = true }
+oxidd-core = { version = "0.9.0" }
+oxidd-dump = { version = "0.4.0" }
 rayon = { workspace = true }
 salsa = { workspace = true }
 tracing = { workspace = true, features = ["release_max_level_debug"] }

crates/red_knot/src/main.rs

@@ -105,8 +105,44 @@ pub enum Command {
     Server,
 }
 
+use oxidd::bdd::BDDFunction;
+use oxidd::ManagerRef;
+use oxidd::{BooleanFunction, BooleanFunctionQuant};
+use oxidd_core::Manager;
+use oxidd_dump::dot::dump_all;
+
 #[allow(clippy::print_stdout, clippy::unnecessary_wraps, clippy::print_stderr)]
 pub fn main() -> ExitStatus {
+    let mgr = oxidd::bdd::new_manager(24, 24, 1);
+    let (x, y, z) = mgr.with_manager_exclusive(|mgr| {
+        (
+            BDDFunction::new_var(mgr).unwrap(),
+            BDDFunction::new_var(mgr).unwrap(),
+            BDDFunction::new_var(mgr).unwrap(),
+        )
+    });
+    mgr.with_manager_shared(|manager| {
+        let inner_func = x
+            .or(&y.and(&x.not().unwrap()).unwrap())
+            .unwrap()
+            .or(&y.not().unwrap().and(&x.not().unwrap()).unwrap())
+            .unwrap();
+        let func = z.and(&inner_func).unwrap();
+
+        let func = func.restrict(&z).unwrap();
+
+        manager.gc();
+
+        let file = std::fs::File::create("bdd.dot").expect("could not create `bdd.dot`");
+        dump_all(
+            file,
+            manager,
+            [(&x, "x"), (&y, "y"), (&z, "z")],
+            [(&func, "z ^ (x ∨ (y ∧ ~x) ∨ (~y ∧ ~x))")],
+        )
+        .expect("dot export failed");
+    });
+    panic!("FOO");
     run().unwrap_or_else(|error| {
         use std::io::Write;
 
@@ -279,7 +315,7 @@ impl MainLoop {
         while let Ok(message) = self.receiver.recv() {
             match message {
                 MainLoopMessage::CheckWorkspace => {
-                    let db = db.snapshot();
+                    let db = db.clone();
                     let sender = self.sender.clone();
 
                     // Spawn a new task that checks the workspace. This needs to be done in a separate thread

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

@@ -3,43 +3,59 @@
 The `typing` module has various aliases to other stdlib classes. These are a legacy feature, but
 still need to be supported by a type checker.
 
-## Currently unsupported
+## Correspondence
 
-Support for most of these symbols is currently a TODO:
+All of the following symbols can be mapped one-to-one with the actual type:
 
 ```py
 import typing
 
 def f(
-    a: typing.List,
-    b: typing.List[int],
-    c: typing.Dict,
-    d: typing.Dict[int, str],
-    e: typing.DefaultDict,
-    f: typing.DefaultDict[str, int],
-    g: typing.Set,
-    h: typing.Set[int],
-    i: typing.FrozenSet,
-    j: typing.FrozenSet[str],
-    k: typing.OrderedDict,
-    l: typing.OrderedDict[int, str],
-    m: typing.Counter,
-    n: typing.Counter[int],
+    list_bare: typing.List,
+    list_parametrized: typing.List[int],
+    dict_bare: typing.Dict,
+    dict_parametrized: typing.Dict[int, str],
+    set_bare: typing.Set,
+    set_parametrized: typing.Set[int],
+    frozen_set_bare: typing.FrozenSet,
+    frozen_set_parametrized: typing.FrozenSet[str],
+    chain_map_bare: typing.ChainMap,
+    chain_map_parametrized: typing.ChainMap[int],
+    counter_bare: typing.Counter,
+    counter_parametrized: typing.Counter[int],
+    default_dict_bare: typing.DefaultDict,
+    default_dict_parametrized: typing.DefaultDict[str, int],
+    deque_bare: typing.Deque,
+    deque_parametrized: typing.Deque[str],
+    ordered_dict_bare: typing.OrderedDict,
+    ordered_dict_parametrized: typing.OrderedDict[int, str],
 ):
-    reveal_type(a)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(b)  # revealed: @Todo(typing.List alias)
-    reveal_type(c)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(d)  # revealed: @Todo(typing.Dict alias)
-    reveal_type(e)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(f)  # revealed: @Todo(typing.DefaultDict[] alias)
-    reveal_type(g)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(h)  # revealed: @Todo(typing.Set alias)
-    reveal_type(i)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(j)  # revealed: @Todo(typing.FrozenSet alias)
-    reveal_type(k)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(l)  # revealed: @Todo(typing.OrderedDict alias)
-    reveal_type(m)  # revealed: @Todo(Unsupported or invalid type in a type expression)
-    reveal_type(n)  # revealed: @Todo(typing.Counter[] alias)
+    reveal_type(list_bare)  # revealed: list
+    reveal_type(list_parametrized)  # revealed: list
+
+    reveal_type(dict_bare)  # revealed: dict
+    reveal_type(dict_parametrized)  # revealed: dict
+
+    reveal_type(set_bare)  # revealed: set
+    reveal_type(set_parametrized)  # revealed: set
+
+    reveal_type(frozen_set_bare)  # revealed: frozenset
+    reveal_type(frozen_set_parametrized)  # revealed: frozenset
+
+    reveal_type(chain_map_bare)  # revealed: ChainMap
+    reveal_type(chain_map_parametrized)  # revealed: ChainMap
+
+    reveal_type(counter_bare)  # revealed: Counter
+    reveal_type(counter_parametrized)  # revealed: Counter
+
+    reveal_type(default_dict_bare)  # revealed: defaultdict
+    reveal_type(default_dict_parametrized)  # revealed: defaultdict
+
+    reveal_type(deque_bare)  # revealed: deque
+    reveal_type(deque_parametrized)  # revealed: deque
+
+    reveal_type(ordered_dict_bare)  # revealed: OrderedDict
+    reveal_type(ordered_dict_parametrized)  # revealed: OrderedDict
 ```
 
 ## Inheritance
@@ -49,35 +65,63 @@ The aliases can be inherited from. Some of these are still partially or wholly T
 ```py
 import typing
 
-class A(typing.Dict): ...
+####################
+### Built-ins
+
+class ListSubclass(typing.List): ...
 
 # TODO: should have `Generic`, should not have `Unknown`
-reveal_type(A.__mro__)  # revealed: tuple[Literal[A], Literal[dict], Unknown, Literal[object]]
+# revealed: tuple[Literal[ListSubclass], Literal[list], Unknown, Literal[object]]
+reveal_type(ListSubclass.__mro__)
 
-class B(typing.List): ...
+class DictSubclass(typing.Dict): ...
 
 # TODO: should have `Generic`, should not have `Unknown`
-reveal_type(B.__mro__)  # revealed: tuple[Literal[B], Literal[list], Unknown, Literal[object]]
+# revealed: tuple[Literal[DictSubclass], Literal[dict], Unknown, Literal[object]]
+reveal_type(DictSubclass.__mro__)
 
-class C(typing.Set): ...
+class SetSubclass(typing.Set): ...
 
 # TODO: should have `Generic`, should not have `Unknown`
-reveal_type(C.__mro__)  # revealed: tuple[Literal[C], Literal[set], Unknown, Literal[object]]
+# revealed: tuple[Literal[SetSubclass], Literal[set], Unknown, Literal[object]]
+reveal_type(SetSubclass.__mro__)
 
-class D(typing.FrozenSet): ...
+class FrozenSetSubclass(typing.FrozenSet): ...
 
 # TODO: should have `Generic`, should not have `Unknown`
-reveal_type(D.__mro__)  # revealed: tuple[Literal[D], Literal[frozenset], Unknown, Literal[object]]
+# revealed: tuple[Literal[FrozenSetSubclass], Literal[frozenset], Unknown, Literal[object]]
+reveal_type(FrozenSetSubclass.__mro__)
 
-class E(typing.DefaultDict): ...
+####################
+### `collections`
 
-reveal_type(E.__mro__)  # revealed: tuple[Literal[E], @Todo(Support for more typing aliases as base classes), Literal[object]]
+class ChainMapSubclass(typing.ChainMap): ...
 
-class F(typing.OrderedDict): ...
+# TODO: Should be (ChainMapSubclass, ChainMap, MutableMapping, Mapping, Collection, Sized, Iterable, Container, Generic, object)
+# revealed: tuple[Literal[ChainMapSubclass], Literal[ChainMap], Unknown, Literal[object]]
+reveal_type(ChainMapSubclass.__mro__)
 
-reveal_type(F.__mro__)  # revealed: tuple[Literal[F], @Todo(Support for more typing aliases as base classes), Literal[object]]
+class CounterSubclass(typing.Counter): ...
 
-class G(typing.Counter): ...
+# TODO: Should be (CounterSubclass, Counter, dict, MutableMapping, Mapping, Collection, Sized, Iterable, Container, Generic, object)
+# revealed: tuple[Literal[CounterSubclass], Literal[Counter], Unknown, Literal[object]]
+reveal_type(CounterSubclass.__mro__)
 
-reveal_type(G.__mro__)  # revealed: tuple[Literal[G], @Todo(Support for more typing aliases as base classes), Literal[object]]
+class DefaultDictSubclass(typing.DefaultDict): ...
+
+# TODO: Should be (DefaultDictSubclass, defaultdict, dict, MutableMapping, Mapping, Collection, Sized, Iterable, Container, Generic, object)
+# revealed: tuple[Literal[DefaultDictSubclass], Literal[defaultdict], Unknown, Literal[object]]
+reveal_type(DefaultDictSubclass.__mro__)
+
+class DequeSubclass(typing.Deque): ...
+
+# TODO: Should be (DequeSubclass, deque, MutableSequence, Sequence, Reversible, Collection, Sized, Iterable, Container, Generic, object)
+# revealed: tuple[Literal[DequeSubclass], Literal[deque], Unknown, Literal[object]]
+reveal_type(DequeSubclass.__mro__)
+
+class OrderedDictSubclass(typing.OrderedDict): ...
+
+# TODO: Should be (OrderedDictSubclass, OrderedDict, dict, MutableMapping, Mapping, Collection, Sized, Iterable, Container, Generic, object)
+# revealed: tuple[Literal[OrderedDictSubclass], Literal[OrderedDict], Unknown, Literal[object]]
+reveal_type(OrderedDictSubclass.__mro__)
 ```

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

@@ -51,7 +51,7 @@ class D(TypeIs): ...  # error: [invalid-base]
 class E(Concatenate): ...  # error: [invalid-base]
 class F(Callable): ...
 
-reveal_type(F.__mro__)  # revealed: tuple[Literal[F], @Todo(Support for more typing aliases as base classes), Literal[object]]
+reveal_type(F.__mro__)  # revealed: tuple[Literal[F], @Todo(Support for Callable as a base class), Literal[object]]
 ```
 
 ## Subscriptability

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

@@ -67,6 +67,6 @@ def _(flag: bool):
             def __call__(self) -> int: ...
 
     a = NonCallable()
-    # error: "Object of type `Literal[1] | Literal[__call__]` is not callable (due to union element `Literal[1]`)"
-    reveal_type(a())  # revealed: Unknown | int
+    # error: "Object of type `Literal[__call__] | Literal[1]` is not callable (due to union element `Literal[1]`)"
+    reveal_type(a())  # revealed: int | Unknown
 ```

crates/red_knot_python_semantic/resources/mdtest/declaration/error.md

@@ -19,14 +19,17 @@ def _(flag: bool):
     x = 1  # error: [conflicting-declarations] "Conflicting declared types for `x`: str, int"
 ```
 
-## Partial declarations
+## Incompatible declarations for 2 (out of 3) types
 
 ```py
-def _(flag: bool):
-    if flag:
+def _(flag1: bool, flag2: bool):
+    if flag1:
+        x: str
+    elif flag2:
         x: int
 
-    x = 1  # error: [conflicting-declarations] "Conflicting declared types for `x`: Unknown, int"
+    # Here, the declared type for `x` is `int | str | Unknown`.
+    x = 1  # error: [conflicting-declarations] "Conflicting declared types for `x`: str, int"
 ```
 
 ## Incompatible declarations with bad assignment
@@ -42,3 +45,31 @@ def _(flag: bool):
     # error: [invalid-assignment]
     x = b"foo"
 ```
+
+## No errors
+
+Currently, we avoid raising the conflicting-declarations for the following cases:
+
+### Partial declarations
+
+```py
+def _(flag: bool):
+    if flag:
+        x: int
+
+    x = 1
+```
+
+### Partial declarations in try-except
+
+Refer to <https://github.com/astral-sh/ruff/issues/13966>
+
+```py
+def _():
+    try:
+        x: int = 1
+    except:
+        x = 2
+
+    x = 3
+```

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

@@ -25,3 +25,82 @@ reveal_type(D)  # revealed: Literal[C]
 ```py path=b.py
 class C: ...
 ```
+
+## Nested
+
+```py
+import a.b
+
+reveal_type(a.b.C)  # revealed: Literal[C]
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b.py
+class C: ...
+```
+
+## Deeply nested
+
+```py
+import a.b.c
+
+reveal_type(a.b.c.C)  # revealed: Literal[C]
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b/__init__.py
+```
+
+```py path=a/b/c.py
+class C: ...
+```
+
+## Nested with rename
+
+```py
+import a.b as b
+
+reveal_type(b.C)  # revealed: Literal[C]
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b.py
+class C: ...
+```
+
+## Deeply nested with rename
+
+```py
+import a.b.c as c
+
+reveal_type(c.C)  # revealed: Literal[C]
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b/__init__.py
+```
+
+```py path=a/b/c.py
+class C: ...
+```
+
+## Unresolvable submodule imports
+
+```py
+# Topmost component resolvable, submodule not resolvable:
+import a.foo  # error: [unresolved-import] "Cannot resolve import `a.foo`"
+
+# Topmost component unresolvable:
+import b.foo  # error: [unresolved-import] "Cannot resolve import `b.foo`"
+```
+
+```py path=a/__init__.py
+```

crates/red_knot_python_semantic/resources/mdtest/import/invalid_syntax.md

@@ -7,3 +7,25 @@ from import bar  # error: [invalid-syntax]
 
 reveal_type(bar)  # revealed: Unknown
 ```
+
+## Invalid nested module import
+
+TODO: This is correctly flagged as an error, but we could clean up the diagnostics that we report.
+
+```py
+# TODO: No second diagnostic
+# error: [invalid-syntax] "Expected ',', found '.'"
+# error: [unresolved-import] "Module `a` has no member `c`"
+from a import b.c
+
+# TODO: Should these be inferred as Unknown?
+reveal_type(b)  # revealed: <module 'a.b'>
+reveal_type(b.c)  # revealed: Literal[1]
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b.py
+c = 1
+```

crates/red_knot_python_semantic/resources/mdtest/import/relative.md

@@ -121,23 +121,44 @@ X = 42
 ```
 
 ```py path=package/bar.py
-# TODO: support submodule imports
-from . import foo  # error: [unresolved-import]
+from . import foo
 
-y = foo.X
-
-# TODO: should be `Literal[42]`
-reveal_type(y)  # revealed: Unknown
+reveal_type(foo.X)  # revealed: Literal[42]
 ```
 
 ## Non-existent + bare to module
 
+This test verifies that we emit an error when we try to import a symbol that is neither a submodule
+nor an attribute of `package`.
+
 ```py path=package/__init__.py
 ```
 
 ```py path=package/bar.py
-# TODO: support submodule imports
 from . import foo  # error: [unresolved-import]
 
 reveal_type(foo)  # revealed: Unknown
 ```
+
+## Import submodule from self
+
+We don't currently consider `from...import` statements when building up the `imported_modules` set
+in the semantic index. When accessing an attribute of a module, we only consider it a potential
+submodule when that submodule name appears in the `imported_modules` set. That means that submodules
+that are imported via `from...import` are not visible to our type inference if you also access that
+submodule via the attribute on its parent package.
+
+```py path=package/__init__.py
+```
+
+```py path=package/foo.py
+X = 42
+```
+
+```py path=package/bar.py
+from . import foo
+import package
+
+# error: [unresolved-attribute] "Type `<module 'package'>` has no attribute `foo`"
+reveal_type(package.foo.X)  # revealed: Unknown
+```

crates/red_knot_python_semantic/resources/mdtest/import/tracking.md

@@ -0,0 +1,100 @@
+# Tracking imported modules
+
+These tests depend on how we track which modules have been imported. There are currently two
+characteristics of our module tracking that can lead to inaccuracies:
+
+- Imports are tracked on a per-file basis. At runtime, importing a submodule in one file makes that
+    submodule globally available via any reference to the containing package. We will flag an error
+    if a file tries to access a submodule without there being an import of that submodule _in that
+    same file_.
+
+    This is a purposeful decision, and not one we plan to change. If a module wants to re-export some
+    other module that it imports, there are ways to do that (tested below) that are blessed by the
+    typing spec and that are visible to our file-scoped import tracking.
+
+- Imports are tracked flow-insensitively: submodule accesses are allowed and resolved if that
+    submodule is imported _anywhere in the file_. This handles the common case where all imports are
+    grouped at the top of the file, and is easiest to implement. We might revisit this decision and
+    track submodule imports flow-sensitively, in which case we will have to update the assertions in
+    some of these tests.
+
+## Import submodule later in file
+
+This test highlights our flow-insensitive analysis, since we access the `a.b` submodule before it
+has been imported.
+
+```py
+import a
+
+# Would be an error with flow-sensitive tracking
+reveal_type(a.b.C)  # revealed: Literal[C]
+
+import a.b
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b.py
+class C: ...
+```
+
+## Rename a re-export
+
+This test highlights how import tracking is local to each file, but specifically to the file where a
+containing module is first referenced. This allows the main module to see that `q.a` contains a
+submodule `b`, even though `a.b` is never imported in the main module.
+
+```py
+from q import a, b
+
+reveal_type(b)  # revealed: <module 'a.b'>
+reveal_type(b.C)  # revealed: Literal[C]
+
+reveal_type(a.b)  # revealed: <module 'a.b'>
+reveal_type(a.b.C)  # revealed: Literal[C]
+```
+
+```py path=a/__init__.py
+```
+
+```py path=a/b.py
+class C: ...
+```
+
+```py path=q.py
+import a as a
+import a.b as b
+```
+
+## Attribute overrides submodule
+
+Technically, either a submodule or a non-module attribute could shadow the other, depending on the
+ordering of when the submodule is loaded relative to the parent module's `__init__.py` file being
+evaluated. We have chosen to always have the submodule take priority. (This matches pyright's
+current behavior, and opposite of mypy's current behavior.)
+
+```py
+import sub.b
+import attr.b
+
+# In the Python interpreter, `attr.b` is Literal[1]
+reveal_type(sub.b)  # revealed: <module 'sub.b'>
+reveal_type(attr.b)  # revealed: <module 'attr.b'>
+```
+
+```py path=sub/__init__.py
+b = 1
+```
+
+```py path=sub/b.py
+```
+
+```py path=attr/__init__.py
+from . import b as _
+
+b = 1
+```
+
+```py path=attr/b.py
+```

crates/red_knot_python_semantic/resources/mdtest/narrow/truthiness.md

@@ -0,0 +1,221 @@
+# Narrowing For Truthiness Checks (`if x` or `if not x`)
+
+## Value Literals
+
+```py
+def foo() -> Literal[0, -1, True, False, "", "foo", b"", b"bar", None] | tuple[()]:
+    return 0
+
+x = foo()
+
+if x:
+    reveal_type(x)  # revealed: Literal[-1] | Literal[True] | Literal["foo"] | Literal[b"bar"]
+else:
+    reveal_type(x)  # revealed: Literal[0] | Literal[False] | Literal[""] | Literal[b""] | None | tuple[()]
+
+if not x:
+    reveal_type(x)  # revealed: Literal[0] | Literal[False] | Literal[""] | Literal[b""] | None | tuple[()]
+else:
+    reveal_type(x)  # revealed: Literal[-1] | Literal[True] | Literal["foo"] | Literal[b"bar"]
+
+if x and not x:
+    reveal_type(x)  # revealed: Never
+else:
+    reveal_type(x)  # revealed: Literal[-1, 0] | bool | Literal["", "foo"] | Literal[b"", b"bar"] | None | tuple[()]
+
+if not (x and not x):
+    reveal_type(x)  # revealed: Literal[-1, 0] | bool | Literal["", "foo"] | Literal[b"", b"bar"] | None | tuple[()]
+else:
+    reveal_type(x)  # revealed: Never
+
+if x or not x:
+    reveal_type(x)  # revealed: Literal[-1, 0] | bool | Literal["foo", ""] | Literal[b"bar", b""] | None | tuple[()]
+else:
+    reveal_type(x)  # revealed: Never
+
+if not (x or not x):
+    reveal_type(x)  # revealed: Never
+else:
+    reveal_type(x)  # revealed: Literal[-1, 0] | bool | Literal["foo", ""] | Literal[b"bar", b""] | None | tuple[()]
+
+if (isinstance(x, int) or isinstance(x, str)) and x:
+    reveal_type(x)  # revealed: Literal[-1] | Literal[True] | Literal["foo"]
+else:
+    reveal_type(x)  # revealed: Literal[b"", b"bar"] | None | tuple[()] | Literal[0] | Literal[False] | Literal[""]
+```
+
+## Function Literals
+
+Basically functions are always truthy.
+
+```py
+def flag() -> bool:
+    return True
+
+def foo(hello: int) -> bytes:
+    return b""
+
+def bar(world: str, *args, **kwargs) -> float:
+    return 0.0
+
+x = foo if flag() else bar
+
+if x:
+    reveal_type(x)  # revealed: Literal[foo, bar]
+else:
+    reveal_type(x)  # revealed: Never
+```
+
+## Mutable Truthiness
+
+### Truthiness of Instances
+
+The boolean value of an instance is not always consistent. For example, `__bool__` can be customized
+to return random values, or in the case of a `list()`, the result depends on the number of elements
+in the list. Therefore, these types should not be narrowed by `if x` or `if not x`.
+
+```py
+class A: ...
+class B: ...
+
+def f(x: A | B):
+    if x:
+        reveal_type(x)  # revealed: A & ~AlwaysFalsy | B & ~AlwaysFalsy
+    else:
+        reveal_type(x)  # revealed: A & ~AlwaysTruthy | B & ~AlwaysTruthy
+
+    if x and not x:
+        reveal_type(x)  # revealed: A & ~AlwaysFalsy & ~AlwaysTruthy | B & ~AlwaysFalsy & ~AlwaysTruthy
+    else:
+        reveal_type(x)  # revealed: A & ~AlwaysTruthy | B & ~AlwaysTruthy | A & ~AlwaysFalsy | B & ~AlwaysFalsy
+
+    if x or not x:
+        reveal_type(x)  # revealed: A & ~AlwaysFalsy | B & ~AlwaysFalsy | A & ~AlwaysTruthy | B & ~AlwaysTruthy
+    else:
+        reveal_type(x)  # revealed: A & ~AlwaysTruthy & ~AlwaysFalsy | B & ~AlwaysTruthy & ~AlwaysFalsy
+```
+
+### Truthiness of Types
+
+Also, types may not be Truthy. This is because `__bool__` can be customized via a metaclass.
+Although this is a very rare case, we may consider metaclass checks in the future to handle this
+more accurately.
+
+```py
+def flag() -> bool:
+    return True
+
+x = int if flag() else str
+reveal_type(x)  # revealed: Literal[int, str]
+
+if x:
+    reveal_type(x)  # revealed: Literal[int] & ~AlwaysFalsy | Literal[str] & ~AlwaysFalsy
+else:
+    reveal_type(x)  # revealed: Literal[int] & ~AlwaysTruthy | Literal[str] & ~AlwaysTruthy
+```
+
+## Determined Truthiness
+
+Some custom classes can have a boolean value that is consistently determined as either `True` or
+`False`, regardless of the instance's state. This is achieved by defining a `__bool__` method that
+always returns a fixed value.
+
+These types can always be fully narrowed in boolean contexts, as shown below:
+
+```py
+class T:
+    def __bool__(self) -> Literal[True]:
+        return True
+
+class F:
+    def __bool__(self) -> Literal[False]:
+        return False
+
+t = T()
+
+if t:
+    reveal_type(t)  # revealed: T
+else:
+    reveal_type(t)  # revealed: Never
+
+f = F()
+
+if f:
+    reveal_type(f)  # revealed: Never
+else:
+    reveal_type(f)  # revealed: F
+```
+
+## Narrowing Complex Intersection and Union
+
+```py
+class A: ...
+class B: ...
+
+def flag() -> bool:
+    return True
+
+def instance() -> A | B:
+    return A()
+
+def literals() -> Literal[0, 42, "", "hello"]:
+    return 42
+
+x = instance()
+y = literals()
+
+if isinstance(x, str) and not isinstance(x, B):
+    reveal_type(x)  # revealed: A & str & ~B
+    reveal_type(y)  # revealed: Literal[0, 42] | Literal["", "hello"]
+
+    z = x if flag() else y
+
+    reveal_type(z)  # revealed: A & str & ~B | Literal[0, 42] | Literal["", "hello"]
+
+    if z:
+        reveal_type(z)  # revealed: A & str & ~B & ~AlwaysFalsy | Literal[42] | Literal["hello"]
+    else:
+        reveal_type(z)  # revealed: A & str & ~B & ~AlwaysTruthy | Literal[0] | Literal[""]
+```
+
+## Narrowing Multiple Variables
+
+```py
+def f(x: Literal[0, 1], y: Literal["", "hello"]):
+    if x and y and not x and not y:
+        reveal_type(x)  # revealed: Never
+        reveal_type(y)  # revealed: Never
+    else:
+        # ~(x or not x) and ~(y or not y)
+        reveal_type(x)  # revealed: Literal[0, 1]
+        reveal_type(y)  # revealed: Literal["", "hello"]
+
+    if (x or not x) and (y and not y):
+        reveal_type(x)  # revealed: Literal[0, 1]
+        reveal_type(y)  # revealed: Never
+    else:
+        # ~(x or not x) or ~(y and not y)
+        reveal_type(x)  # revealed: Literal[0, 1]
+        reveal_type(y)  # revealed: Literal["", "hello"]
+```
+
+## ControlFlow Merging
+
+After merging control flows, when we take the union of all constraints applied in each branch, we
+should return to the original state.
+
+```py
+class A: ...
+
+x = A()
+
+if x and not x:
+    y = x
+    reveal_type(y)  # revealed: A & ~AlwaysFalsy & ~AlwaysTruthy
+else:
+    y = x
+    reveal_type(y)  # revealed: A & ~AlwaysTruthy | A & ~AlwaysFalsy
+
+# TODO: It should be A. We should improve UnionBuilder or IntersectionBuilder. (issue #15023)
+reveal_type(y)  # revealed: A & ~AlwaysTruthy | A & ~AlwaysFalsy
+```

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

@@ -61,10 +61,8 @@ class B: ...
 ```py path=a/test.py
 import a.b
 
-# TODO: no diagnostic
-# error: [unresolved-attribute]
 def f(c: type[a.b.C]):
-    reveal_type(c)  # revealed: @Todo(unsupported type[X] special form)
+    reveal_type(c)  # revealed: type[C]
 ```
 
 ```py path=a/__init__.py

crates/red_knot_python_semantic/src/db.rs

@@ -27,6 +27,7 @@ pub(crate) mod tests {
     use ruff_db::{Db as SourceDb, Upcast};
 
     #[salsa::db]
+    #[derive(Clone)]
     pub(crate) struct TestDb {
         storage: salsa::Storage<Self>,
         files: Files,

crates/red_knot_python_semantic/src/module_name.rs

@@ -186,6 +186,26 @@ impl ModuleName {
         self.0.push('.');
         self.0.push_str(other);
     }
+
+    /// Returns an iterator of this module name and all of its parent modules.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// use red_knot_python_semantic::ModuleName;
+    ///
+    /// assert_eq!(
+    ///     ModuleName::new_static("foo.bar.baz").unwrap().ancestors().collect::<Vec<_>>(),
+    ///     vec![
+    ///         ModuleName::new_static("foo.bar.baz").unwrap(),
+    ///         ModuleName::new_static("foo.bar").unwrap(),
+    ///         ModuleName::new_static("foo").unwrap(),
+    ///     ],
+    /// );
+    /// ```
+    pub fn ancestors(&self) -> impl Iterator<Item = Self> {
+        std::iter::successors(Some(self.clone()), Self::parent)
+    }
 }
 
 impl Deref for ModuleName {

crates/red_knot_python_semantic/src/module_resolver/module.rs

@@ -7,7 +7,7 @@ use super::path::SearchPath;
 use crate::module_name::ModuleName;
 
 /// Representation of a Python module.
-#[derive(Clone, PartialEq, Eq)]
+#[derive(Clone, PartialEq, Eq, Hash)]
 pub struct Module {
     inner: Arc<ModuleInner>,
 }
@@ -61,7 +61,7 @@ impl std::fmt::Debug for Module {
     }
 }
 
-#[derive(PartialEq, Eq)]
+#[derive(PartialEq, Eq, Hash)]
 struct ModuleInner {
     name: ModuleName,
     kind: ModuleKind,

crates/red_knot_python_semantic/src/module_resolver/resolver.rs

@@ -73,6 +73,15 @@ enum SystemOrVendoredPathRef<'a> {
     Vendored(&'a VendoredPath),
 }
 
+impl std::fmt::Display for SystemOrVendoredPathRef<'_> {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            SystemOrVendoredPathRef::System(system) => system.fmt(f),
+            SystemOrVendoredPathRef::Vendored(vendored) => vendored.fmt(f),
+        }
+    }
+}
+
 /// Resolves the module for the file with the given id.
 ///
 /// Returns `None` if the file is not a module locatable via any of the known search paths.

crates/red_knot_python_semantic/src/semantic_index.rs

@@ -1,13 +1,14 @@
 use std::iter::FusedIterator;
 use std::sync::Arc;
 
-use rustc_hash::{FxBuildHasher, FxHashMap};
+use rustc_hash::{FxBuildHasher, FxHashMap, FxHashSet};
 use salsa::plumbing::AsId;
 
 use ruff_db::files::File;
 use ruff_db::parsed::parsed_module;
 use ruff_index::{IndexSlice, IndexVec};
 
+use crate::module_name::ModuleName;
 use crate::semantic_index::ast_ids::node_key::ExpressionNodeKey;
 use crate::semantic_index::ast_ids::AstIds;
 use crate::semantic_index::builder::SemanticIndexBuilder;
@@ -60,6 +61,22 @@ pub(crate) fn symbol_table<'db>(db: &'db dyn Db, scope: ScopeId<'db>) -> Arc<Sym
     index.symbol_table(scope.file_scope_id(db))
 }
 
+/// Returns the set of modules that are imported anywhere in `file`.
+///
+/// This set only considers `import` statements, not `from...import` statements, because:
+///
+///   - In `from foo import bar`, we cannot determine whether `foo.bar` is a submodule (and is
+///     therefore imported) without looking outside the content of this file.  (We could turn this
+///     into a _potentially_ imported modules set, but that would change how it's used in our type
+///     inference logic.)
+///
+///   - We cannot resolve relative imports (which aren't allowed in `import` statements) without
+///     knowing the name of the current module, and whether it's a package.
+#[salsa::tracked]
+pub(crate) fn imported_modules<'db>(db: &'db dyn Db, file: File) -> Arc<FxHashSet<ModuleName>> {
+    semantic_index(db, file).imported_modules.clone()
+}
+
 /// Returns the use-def map for a specific `scope`.
 ///
 /// Using [`use_def_map`] over [`semantic_index`] has the advantage that
@@ -116,6 +133,9 @@ pub(crate) struct SemanticIndex<'db> {
     /// changing a file invalidates all dependents.
     ast_ids: IndexVec<FileScopeId, AstIds>,
 
+    /// The set of modules that are imported anywhere within this file.
+    imported_modules: Arc<FxHashSet<ModuleName>>,
+
     /// Flags about the global scope (code usage impacting inference)
     has_future_annotations: bool,
 }

crates/red_knot_python_semantic/src/semantic_index/builder.rs

@@ -1,7 +1,7 @@
 use std::sync::Arc;
 
 use except_handlers::TryNodeContextStackManager;
-use rustc_hash::FxHashMap;
+use rustc_hash::{FxHashMap, FxHashSet};
 
 use ruff_db::files::File;
 use ruff_db::parsed::ParsedModule;
@@ -12,6 +12,7 @@ use ruff_python_ast::visitor::{walk_expr, walk_pattern, walk_stmt, Visitor};
 use ruff_python_ast::{BoolOp, Expr};
 
 use crate::ast_node_ref::AstNodeRef;
+use crate::module_name::ModuleName;
 use crate::semantic_index::ast_ids::node_key::ExpressionNodeKey;
 use crate::semantic_index::ast_ids::AstIdsBuilder;
 use crate::semantic_index::definition::{
@@ -79,6 +80,7 @@ pub(super) struct SemanticIndexBuilder<'db> {
     scopes_by_expression: FxHashMap<ExpressionNodeKey, FileScopeId>,
     definitions_by_node: FxHashMap<DefinitionNodeKey, Definition<'db>>,
     expressions_by_node: FxHashMap<ExpressionNodeKey, Expression<'db>>,
+    imported_modules: FxHashSet<ModuleName>,
 }
 
 impl<'db> SemanticIndexBuilder<'db> {
@@ -105,6 +107,8 @@ impl<'db> SemanticIndexBuilder<'db> {
             scopes_by_node: FxHashMap::default(),
             definitions_by_node: FxHashMap::default(),
             expressions_by_node: FxHashMap::default(),
+
+            imported_modules: FxHashSet::default(),
         };
 
         builder.push_scope_with_parent(NodeWithScopeRef::Module, None);
@@ -558,6 +562,7 @@ impl<'db> SemanticIndexBuilder<'db> {
             scopes_by_expression: self.scopes_by_expression,
             scopes_by_node: self.scopes_by_node,
             use_def_maps,
+            imported_modules: Arc::new(self.imported_modules),
             has_future_annotations: self.has_future_annotations,
         }
     }
@@ -661,6 +666,12 @@ where
             }
             ast::Stmt::Import(node) => {
                 for alias in &node.names {
+                    // Mark the imported module, and all of its parents, as being imported in this
+                    // file.
+                    if let Some(module_name) = ModuleName::new(&alias.name) {
+                        self.imported_modules.extend(module_name.ancestors());
+                    }
+
                     let symbol_name = if let Some(asname) = &alias.asname {
                         asname.id.clone()
                     } else {

crates/red_knot_python_semantic/src/stdlib.rs

@@ -17,6 +17,7 @@ pub(crate) enum CoreStdlibModule {
     Sys,
     #[allow(dead_code)]
     Abc, // currently only used in tests
+    Collections,
 }
 
 impl CoreStdlibModule {
@@ -29,6 +30,7 @@ impl CoreStdlibModule {
             Self::TypingExtensions => "typing_extensions",
             Self::Sys => "sys",
             Self::Abc => "abc",
+            Self::Collections => "collections",
         }
     }
 

crates/red_knot_python_semantic/src/types.rs

@@ -14,13 +14,14 @@ pub(crate) use self::infer::{
     infer_deferred_types, infer_definition_types, infer_expression_types, infer_scope_types,
 };
 pub(crate) use self::signatures::Signature;
-use crate::module_resolver::file_to_module;
+use crate::module_name::ModuleName;
+use crate::module_resolver::{file_to_module, resolve_module};
 use crate::semantic_index::ast_ids::HasScopedExpressionId;
 use crate::semantic_index::definition::Definition;
 use crate::semantic_index::symbol::{self as symbol, ScopeId, ScopedSymbolId};
 use crate::semantic_index::{
-    global_scope, semantic_index, symbol_table, use_def_map, BindingWithConstraints,
-    BindingWithConstraintsIterator, DeclarationsIterator,
+    global_scope, imported_modules, semantic_index, symbol_table, use_def_map,
+    BindingWithConstraints, BindingWithConstraintsIterator, DeclarationsIterator,
 };
 use crate::stdlib::{
     builtins_symbol, core_module_symbol, typing_extensions_symbol, CoreStdlibModule,
@@ -291,8 +292,8 @@ type DeclaredTypeResult<'db> = Result<Type<'db>, (Type<'db>, Box<[Type<'db>]>)>;
 /// `Ok(declared_type)`. If there are conflicting declarations, returns
 /// `Err((union_of_declared_types, conflicting_declared_types))`.
 ///
-/// If undeclared is a possibility, `undeclared_ty` type will be part of the return type (and may
-/// conflict with other declarations.)
+/// If undeclared is a possibility, `undeclared_ty` type will be part of the return type but it
+/// will not be considered to be conflicting with any other types.
 ///
 /// # Panics
 /// Will panic if there are no declarations and no `undeclared_ty` is provided. This is a logic
@@ -303,27 +304,31 @@ fn declarations_ty<'db>(
     declarations: DeclarationsIterator<'_, 'db>,
     undeclared_ty: Option<Type<'db>>,
 ) -> DeclaredTypeResult<'db> {
-    let decl_types = declarations.map(|declaration| declaration_ty(db, declaration));
+    let mut declaration_types = declarations.map(|declaration| declaration_ty(db, declaration));
 
-    let mut all_types = undeclared_ty.into_iter().chain(decl_types);
-
-    let first = all_types.next().expect(
-        "declarations_ty must not be called with zero declarations and no may-be-undeclared",
-    );
+    let Some(first) = declaration_types.next() else {
+        if let Some(undeclared_ty) = undeclared_ty {
+            // Short-circuit to return the undeclared type if there are no declarations.
+            return Ok(undeclared_ty);
+        }
+        panic!("declarations_ty must not be called with zero declarations and no undeclared_ty");
+    };
 
     let mut conflicting: Vec<Type<'db>> = vec![];
-    let declared_ty = if let Some(second) = all_types.next() {
-        let mut builder = UnionBuilder::new(db).add(first);
-        for other in [second].into_iter().chain(all_types) {
-            if !first.is_equivalent_to(db, other) {
-                conflicting.push(other);
-            }
-            builder = builder.add(other);
+    let mut builder = UnionBuilder::new(db).add(first);
+    for other in declaration_types {
+        if !first.is_equivalent_to(db, other) {
+            conflicting.push(other);
         }
-        builder.build()
-    } else {
-        first
-    };
+        builder = builder.add(other);
+    }
+    // Avoid considering the undeclared type for the conflicting declaration diagnostics. It
+    // should still be part of the declared type.
+    if let Some(undeclared_ty) = undeclared_ty {
+        builder = builder.add(undeclared_ty);
+    }
+    let declared_ty = builder.build();
+
     if conflicting.is_empty() {
         Ok(declared_ty)
     } else {
@@ -413,7 +418,7 @@ pub enum Type<'db> {
     /// A specific function object
     FunctionLiteral(FunctionType<'db>),
     /// A specific module object
-    ModuleLiteral(File),
+    ModuleLiteral(ModuleLiteralType<'db>),
     /// A specific class object
     ClassLiteral(ClassLiteralType<'db>),
     // The set of all class objects that are subclasses of the given class (C), spelled `type[C]`.
@@ -426,6 +431,11 @@ pub enum Type<'db> {
     Union(UnionType<'db>),
     /// The set of objects in all of the types in the intersection
     Intersection(IntersectionType<'db>),
+    /// Represents objects whose `__bool__` method is deterministic:
+    /// - `AlwaysTruthy`: `__bool__` always returns `True`
+    /// - `AlwaysFalsy`: `__bool__` always returns `False`
+    AlwaysTruthy,
+    AlwaysFalsy,
     /// An integer literal
     IntLiteral(i64),
     /// A boolean literal, either `True` or `False`.
@@ -446,6 +456,10 @@ pub enum Type<'db> {
 }
 
 impl<'db> Type<'db> {
+    pub const fn is_unknown(&self) -> bool {
+        matches!(self, Type::Unknown)
+    }
+
     pub const fn is_never(&self) -> bool {
         matches!(self, Type::Never)
     }
@@ -475,15 +489,19 @@ impl<'db> Type<'db> {
         matches!(self, Type::ClassLiteral(..))
     }
 
-    pub const fn into_module_literal(self) -> Option<File> {
+    pub fn module_literal(db: &'db dyn Db, importing_file: File, submodule: Module) -> Self {
+        Self::ModuleLiteral(ModuleLiteralType::new(db, importing_file, submodule))
+    }
+
+    pub const fn into_module_literal(self) -> Option<ModuleLiteralType<'db>> {
         match self {
-            Type::ModuleLiteral(file) => Some(file),
+            Type::ModuleLiteral(module) => Some(module),
             _ => None,
         }
     }
 
     #[track_caller]
-    pub fn expect_module_literal(self) -> File {
+    pub fn expect_module_literal(self) -> ModuleLiteralType<'db> {
         self.into_module_literal()
             .expect("Expected a Type::ModuleLiteral variant")
     }
@@ -704,6 +722,15 @@ impl<'db> Type<'db> {
                         .all(|&neg_ty| self.is_disjoint_from(db, neg_ty))
             }
 
+            // Note that the definition of `Type::AlwaysFalsy` depends on the return value of `__bool__`.
+            // If `__bool__` always returns True or False, it can be treated as a subtype of `AlwaysTruthy` or `AlwaysFalsy`, respectively.
+            (left, Type::AlwaysFalsy) => matches!(left.bool(db), Truthiness::AlwaysFalse),
+            (left, Type::AlwaysTruthy) => matches!(left.bool(db), Truthiness::AlwaysTrue),
+            // Currently, the only supertype of `AlwaysFalsy` and `AlwaysTruthy` is the universal set (object instance).
+            (Type::AlwaysFalsy | Type::AlwaysTruthy, _) => {
+                target.is_equivalent_to(db, KnownClass::Object.to_instance(db))
+            }
+
             // All `StringLiteral` types are a subtype of `LiteralString`.
             (Type::StringLiteral(_), Type::LiteralString) => true,
 
@@ -1092,6 +1119,16 @@ impl<'db> Type<'db> {
                 false
             }
 
+            (Type::AlwaysTruthy, ty) | (ty, Type::AlwaysTruthy) => {
+                // `Truthiness::Ambiguous` may include `AlwaysTrue` as a subset, so it's not guaranteed to be disjoint.
+                // Thus, they are only disjoint if `ty.bool() == AlwaysFalse`.
+                matches!(ty.bool(db), Truthiness::AlwaysFalse)
+            }
+            (Type::AlwaysFalsy, ty) | (ty, Type::AlwaysFalsy) => {
+                // Similarly, they are only disjoint if `ty.bool() == AlwaysTrue`.
+                matches!(ty.bool(db), Truthiness::AlwaysTrue)
+            }
+
             (Type::KnownInstance(left), right) => {
                 left.instance_fallback(db).is_disjoint_from(db, right)
             }
@@ -1225,7 +1262,9 @@ impl<'db> Type<'db> {
             | Type::LiteralString
             | Type::BytesLiteral(_)
             | Type::SliceLiteral(_)
-            | Type::KnownInstance(_) => true,
+            | Type::KnownInstance(_)
+            | Type::AlwaysFalsy
+            | Type::AlwaysTruthy => true,
             Type::SubclassOf(SubclassOfType { base }) => matches!(base, ClassBase::Class(_)),
             Type::ClassLiteral(_) | Type::Instance(_) => {
                 // TODO: Ideally, we would iterate over the MRO of the class, check if all
@@ -1327,6 +1366,7 @@ impl<'db> Type<'db> {
                 //
                 false
             }
+            Type::AlwaysTruthy | Type::AlwaysFalsy => false,
         }
     }
 
@@ -1380,6 +1420,11 @@ impl<'db> Type<'db> {
                     | KnownClass::ModuleType
                     | KnownClass::FunctionType
                     | KnownClass::SpecialForm
+                    | KnownClass::ChainMap
+                    | KnownClass::Counter
+                    | KnownClass::DefaultDict
+                    | KnownClass::Deque
+                    | KnownClass::OrderedDict
                     | KnownClass::StdlibAlias
                     | KnownClass::TypeVar,
                 ) => false,
@@ -1392,7 +1437,9 @@ impl<'db> Type<'db> {
             | Type::Todo(_)
             | Type::Union(..)
             | Type::Intersection(..)
-            | Type::LiteralString => false,
+            | Type::LiteralString
+            | Type::AlwaysTruthy
+            | Type::AlwaysFalsy => false,
         }
     }
 
@@ -1418,7 +1465,7 @@ impl<'db> Type<'db> {
                 // TODO: attribute lookup on function type
                 todo_type!().into()
             }
-            Type::ModuleLiteral(file) => {
+            Type::ModuleLiteral(module_ref) => {
                 // `__dict__` is a very special member that is never overridden by module globals;
                 // we should always look it up directly as an attribute on `types.ModuleType`,
                 // never in the global scope of the module.
@@ -1428,7 +1475,30 @@ impl<'db> Type<'db> {
                         .member(db, "__dict__");
                 }
 
-                let global_lookup = symbol(db, global_scope(db, *file), name);
+                // If the file that originally imported the module has also imported a submodule
+                // named [name], then the result is (usually) that submodule, even if the module
+                // also defines a (non-module) symbol with that name.
+                //
+                // Note that technically, either the submodule or the non-module symbol could take
+                // priority, depending on the ordering of when the submodule is loaded relative to
+                // the parent module's `__init__.py` file being evaluated.  That said, we have
+                // chosen to always have the submodule take priority.  (This matches pyright's
+                // current behavior, and opposite of mypy's current behavior.)
+                if let Some(submodule_name) = ModuleName::new(name) {
+                    let importing_file = module_ref.importing_file(db);
+                    let imported_submodules = imported_modules(db, importing_file);
+                    let mut full_submodule_name = module_ref.module(db).name().clone();
+                    full_submodule_name.extend(&submodule_name);
+                    if imported_submodules.contains(&full_submodule_name) {
+                        if let Some(submodule) = resolve_module(db, &full_submodule_name) {
+                            let submodule_ty = Type::module_literal(db, importing_file, submodule);
+                            return Symbol::Type(submodule_ty, Boundness::Bound);
+                        }
+                    }
+                }
+
+                let global_lookup =
+                    symbol(db, global_scope(db, module_ref.module(db).file()), name);
 
                 // If it's unbound, check if it's present as an instance on `types.ModuleType`
                 // or `builtins.object`.
@@ -1537,6 +1607,10 @@ impl<'db> Type<'db> {
                 // TODO: implement tuple methods
                 todo_type!().into()
             }
+            Type::AlwaysTruthy | Type::AlwaysFalsy => {
+                // TODO return `Callable[[], Literal[True/False]]` for `__bool__` access
+                KnownClass::Object.to_instance(db).member(db, name)
+            }
             &todo @ Type::Todo(_) => todo.into(),
         }
     }
@@ -1559,6 +1633,8 @@ impl<'db> Type<'db> {
                 // TODO: see above
                 Truthiness::Ambiguous
             }
+            Type::AlwaysTruthy => Truthiness::AlwaysTrue,
+            Type::AlwaysFalsy => Truthiness::AlwaysFalse,
             instance_ty @ Type::Instance(InstanceType { class }) => {
                 if class.is_known(db, KnownClass::NoneType) {
                     Truthiness::AlwaysFalse
@@ -1871,7 +1947,9 @@ impl<'db> Type<'db> {
             | Type::StringLiteral(_)
             | Type::SliceLiteral(_)
             | Type::Tuple(_)
-            | Type::LiteralString => Type::Unknown,
+            | Type::LiteralString
+            | Type::AlwaysTruthy
+            | Type::AlwaysFalsy => Type::Unknown,
         }
     }
 
@@ -1892,6 +1970,28 @@ impl<'db> Type<'db> {
             // We treat `typing.Type` exactly the same as `builtins.type`:
             Type::KnownInstance(KnownInstanceType::Type) => Ok(KnownClass::Type.to_instance(db)),
             Type::KnownInstance(KnownInstanceType::Tuple) => Ok(KnownClass::Tuple.to_instance(db)),
+
+            // Legacy `typing` aliases
+            Type::KnownInstance(KnownInstanceType::List) => Ok(KnownClass::List.to_instance(db)),
+            Type::KnownInstance(KnownInstanceType::Dict) => Ok(KnownClass::Dict.to_instance(db)),
+            Type::KnownInstance(KnownInstanceType::Set) => Ok(KnownClass::Set.to_instance(db)),
+            Type::KnownInstance(KnownInstanceType::FrozenSet) => {
+                Ok(KnownClass::FrozenSet.to_instance(db))
+            }
+            Type::KnownInstance(KnownInstanceType::ChainMap) => {
+                Ok(KnownClass::ChainMap.to_instance(db))
+            }
+            Type::KnownInstance(KnownInstanceType::Counter) => {
+                Ok(KnownClass::Counter.to_instance(db))
+            }
+            Type::KnownInstance(KnownInstanceType::DefaultDict) => {
+                Ok(KnownClass::DefaultDict.to_instance(db))
+            }
+            Type::KnownInstance(KnownInstanceType::Deque) => Ok(KnownClass::Deque.to_instance(db)),
+            Type::KnownInstance(KnownInstanceType::OrderedDict) => {
+                Ok(KnownClass::OrderedDict.to_instance(db))
+            }
+
             Type::Union(union) => {
                 let mut builder = UnionBuilder::new(db);
                 let mut invalid_expressions = smallvec::SmallVec::default();
@@ -2011,6 +2111,7 @@ impl<'db> Type<'db> {
                 ClassBase::try_from_ty(db, todo_type!("Intersection meta-type"))
                     .expect("Type::Todo should be a valid ClassBase"),
             ),
+            Type::AlwaysTruthy | Type::AlwaysFalsy => KnownClass::Type.to_instance(db),
             Type::Todo(todo) => Type::subclass_of_base(ClassBase::Todo(*todo)),
         }
     }
@@ -2153,6 +2254,12 @@ pub enum KnownClass {
     TypeVar,
     TypeAliasType,
     NoDefaultType,
+    // Collections
+    ChainMap,
+    Counter,
+    DefaultDict,
+    Deque,
+    OrderedDict,
     // sys
     VersionInfo,
 }
@@ -2183,6 +2290,11 @@ impl<'db> KnownClass {
             Self::TypeVar => "TypeVar",
             Self::TypeAliasType => "TypeAliasType",
             Self::NoDefaultType => "_NoDefaultType",
+            Self::ChainMap => "ChainMap",
+            Self::Counter => "Counter",
+            Self::DefaultDict => "defaultdict",
+            Self::Deque => "deque",
+            Self::OrderedDict => "OrderedDict",
             // For example, `typing.List` is defined as `List = _Alias()` in typeshed
             Self::StdlibAlias => "_Alias",
             // This is the name the type of `sys.version_info` has in typeshed,
@@ -2246,6 +2358,11 @@ impl<'db> KnownClass {
                     CoreStdlibModule::TypingExtensions
                 }
             }
+            Self::ChainMap
+            | Self::Counter
+            | Self::DefaultDict
+            | Self::Deque
+            | Self::OrderedDict => CoreStdlibModule::Collections,
         }
     }
 
@@ -2273,6 +2390,11 @@ impl<'db> KnownClass {
             | Self::ModuleType
             | Self::FunctionType
             | Self::SpecialForm
+            | Self::ChainMap
+            | Self::Counter
+            | Self::DefaultDict
+            | Self::Deque
+            | Self::OrderedDict
             | Self::StdlibAlias
             | Self::BaseException
             | Self::BaseExceptionGroup
@@ -2305,6 +2427,11 @@ impl<'db> KnownClass {
             "ModuleType" => Self::ModuleType,
             "FunctionType" => Self::FunctionType,
             "TypeAliasType" => Self::TypeAliasType,
+            "ChainMap" => Self::ChainMap,
+            "Counter" => Self::Counter,
+            "defaultdict" => Self::DefaultDict,
+            "deque" => Self::Deque,
+            "OrderedDict" => Self::OrderedDict,
             "_Alias" => Self::StdlibAlias,
             "_SpecialForm" => Self::SpecialForm,
             "_NoDefaultType" => Self::NoDefaultType,
@@ -2336,6 +2463,11 @@ impl<'db> KnownClass {
             | Self::Dict
             | Self::Slice
             | Self::GenericAlias
+            | Self::ChainMap
+            | Self::Counter
+            | Self::DefaultDict
+            | Self::Deque
+            | Self::OrderedDict
             | Self::StdlibAlias  // no equivalent class exists in typing_extensions, nor ever will
             | Self::ModuleType
             | Self::VersionInfo
@@ -2371,6 +2503,24 @@ pub enum KnownInstanceType<'db> {
     Any,
     /// The symbol `typing.Tuple` (which can also be found as `typing_extensions.Tuple`)
     Tuple,
+    /// The symbol `typing.List` (which can also be found as `typing_extensions.List`)
+    List,
+    /// The symbol `typing.Dict` (which can also be found as `typing_extensions.Dict`)
+    Dict,
+    /// The symbol `typing.Set` (which can also be found as `typing_extensions.Set`)
+    Set,
+    /// The symbol `typing.FrozenSet` (which can also be found as `typing_extensions.FrozenSet`)
+    FrozenSet,
+    /// The symbol `typing.ChainMap` (which can also be found as `typing_extensions.ChainMap`)
+    ChainMap,
+    /// The symbol `typing.Counter` (which can also be found as `typing_extensions.Counter`)
+    Counter,
+    /// The symbol `typing.DefaultDict` (which can also be found as `typing_extensions.DefaultDict`)
+    DefaultDict,
+    /// The symbol `typing.Deque` (which can also be found as `typing_extensions.Deque`)
+    Deque,
+    /// The symbol `typing.OrderedDict` (which can also be found as `typing_extensions.OrderedDict`)
+    OrderedDict,
     /// The symbol `typing.Type` (which can also be found as `typing_extensions.Type`)
     Type,
     /// A single instance of `typing.TypeVar`
@@ -2391,15 +2541,6 @@ pub enum KnownInstanceType<'db> {
     TypeAlias,
     TypeGuard,
     TypeIs,
-    List,
-    Dict,
-    DefaultDict,
-    Set,
-    FrozenSet,
-    Counter,
-    Deque,
-    ChainMap,
-    OrderedDict,
     ReadOnly,
     // TODO: fill this enum out with more special forms, etc.
 }
@@ -2860,6 +3001,18 @@ impl KnownFunction {
     }
 }
 
+#[salsa::interned]
+pub struct ModuleLiteralType<'db> {
+    /// The file in which this module was imported.
+    ///
+    /// We need this in order to know which submodules should be attached to it as attributes
+    /// (because the submodules were also imported in this file).
+    pub importing_file: File,
+
+    /// The imported module.
+    pub module: Module,
+}
+
 /// Representation of a runtime class object.
 ///
 /// Does not in itself represent a type,
@@ -3443,6 +3596,8 @@ pub(crate) mod tests {
         SubclassOfAbcClass(&'static str),
         StdlibModule(CoreStdlibModule),
         SliceLiteral(i32, i32, i32),
+        AlwaysTruthy,
+        AlwaysFalsy,
     }
 
     impl Ty {
@@ -3501,7 +3656,8 @@ pub(crate) mod tests {
                         .class,
                 ),
                 Ty::StdlibModule(module) => {
-                    Type::ModuleLiteral(resolve_module(db, &module.name()).unwrap().file())
+                    let module = resolve_module(db, &module.name()).unwrap();
+                    Type::module_literal(db, module.file(), module)
                 }
                 Ty::SliceLiteral(start, stop, step) => Type::SliceLiteral(SliceLiteralType::new(
                     db,
@@ -3509,6 +3665,8 @@ pub(crate) mod tests {
                     Some(stop),
                     Some(step),
                 )),
+                Ty::AlwaysTruthy => Type::AlwaysTruthy,
+                Ty::AlwaysFalsy => Type::AlwaysFalsy,
             }
         }
     }
@@ -3647,6 +3805,12 @@ pub(crate) mod tests {
     )]
     #[test_case(Ty::SliceLiteral(1, 2, 3), Ty::BuiltinInstance("slice"))]
     #[test_case(Ty::SubclassOfBuiltinClass("str"), Ty::Intersection{pos: vec![], neg: vec![Ty::None]})]
+    #[test_case(Ty::IntLiteral(1), Ty::AlwaysTruthy)]
+    #[test_case(Ty::IntLiteral(0), Ty::AlwaysFalsy)]
+    #[test_case(Ty::AlwaysTruthy, Ty::BuiltinInstance("object"))]
+    #[test_case(Ty::AlwaysFalsy, Ty::BuiltinInstance("object"))]
+    #[test_case(Ty::Never, Ty::AlwaysTruthy)]
+    #[test_case(Ty::Never, Ty::AlwaysFalsy)]
     fn is_subtype_of(from: Ty, to: Ty) {
         let db = setup_db();
         assert!(from.into_type(&db).is_subtype_of(&db, to.into_type(&db)));
@@ -3681,6 +3845,10 @@ pub(crate) mod tests {
     #[test_case(Ty::BuiltinClassLiteral("str"), Ty::SubclassOfAny)]
     #[test_case(Ty::AbcInstance("ABCMeta"), Ty::SubclassOfBuiltinClass("type"))]
     #[test_case(Ty::SubclassOfBuiltinClass("str"), Ty::BuiltinClassLiteral("str"))]
+    #[test_case(Ty::IntLiteral(1), Ty::AlwaysFalsy)]
+    #[test_case(Ty::IntLiteral(0), Ty::AlwaysTruthy)]
+    #[test_case(Ty::BuiltinInstance("str"), Ty::AlwaysTruthy)]
+    #[test_case(Ty::BuiltinInstance("str"), Ty::AlwaysFalsy)]
     fn is_not_subtype_of(from: Ty, to: Ty) {
         let db = setup_db();
         assert!(!from.into_type(&db).is_subtype_of(&db, to.into_type(&db)));
@@ -3815,6 +3983,7 @@ pub(crate) mod tests {
     #[test_case(Ty::Tuple(vec![]), Ty::BuiltinClassLiteral("object"))]
     #[test_case(Ty::SubclassOfBuiltinClass("object"), Ty::None)]
     #[test_case(Ty::SubclassOfBuiltinClass("str"), Ty::LiteralString)]
+    #[test_case(Ty::AlwaysFalsy, Ty::AlwaysTruthy)]
     fn is_disjoint_from(a: Ty, b: Ty) {
         let db = setup_db();
         let a = a.into_type(&db);
@@ -3845,6 +4014,8 @@ pub(crate) mod tests {
     #[test_case(Ty::BuiltinClassLiteral("str"), Ty::BuiltinInstance("type"))]
     #[test_case(Ty::BuiltinClassLiteral("str"), Ty::SubclassOfAny)]
     #[test_case(Ty::AbcClassLiteral("ABC"), Ty::AbcInstance("ABCMeta"))]
+    #[test_case(Ty::BuiltinInstance("str"), Ty::AlwaysTruthy)]
+    #[test_case(Ty::BuiltinInstance("str"), Ty::AlwaysFalsy)]
     fn is_not_disjoint_from(a: Ty, b: Ty) {
         let db = setup_db();
         let a = a.into_type(&db);

crates/red_knot_python_semantic/src/types/builder.rs

@@ -30,6 +30,8 @@ use crate::types::{InstanceType, IntersectionType, KnownClass, Type, UnionType};
 use crate::{Db, FxOrderSet};
 use smallvec::SmallVec;
 
+use super::Truthiness;
+
 pub(crate) struct UnionBuilder<'db> {
     elements: Vec<Type<'db>>,
     db: &'db dyn Db,
@@ -243,15 +245,22 @@ impl<'db> InnerIntersectionBuilder<'db> {
             }
         } else {
             // ~Literal[True] & bool = Literal[False]
+            // ~AlwaysTruthy & bool = Literal[False]
             if let Type::Instance(InstanceType { class }) = new_positive {
                 if class.is_known(db, KnownClass::Bool) {
-                    if let Some(&Type::BooleanLiteral(value)) = self
+                    if let Some(new_type) = self
                         .negative
                         .iter()
-                        .find(|element| element.is_boolean_literal())
+                        .find(|element| {
+                            element.is_boolean_literal()
+                                | matches!(element, Type::AlwaysFalsy | Type::AlwaysTruthy)
+                        })
+                        .map(|element| {
+                            Type::BooleanLiteral(element.bool(db) != Truthiness::AlwaysTrue)
+                        })
                     {
                         *self = Self::default();
-                        self.positive.insert(Type::BooleanLiteral(!value));
+                        self.positive.insert(new_type);
                         return;
                     }
                 }
@@ -318,15 +327,15 @@ impl<'db> InnerIntersectionBuilder<'db> {
                 // simplify the representation.
                 self.add_positive(db, ty);
             }
-            // ~Literal[True] & bool = Literal[False]
-            Type::BooleanLiteral(bool)
-                if self
-                    .positive
-                    .iter()
-                    .any(|pos| *pos == KnownClass::Bool.to_instance(db)) =>
+            // bool & ~Literal[True] = Literal[False]
+            // bool & ~AlwaysTruthy = Literal[False]
+            Type::BooleanLiteral(_) | Type::AlwaysFalsy | Type::AlwaysTruthy
+                if self.positive.contains(&KnownClass::Bool.to_instance(db)) =>
             {
                 *self = Self::default();
-                self.positive.insert(Type::BooleanLiteral(!bool));
+                self.positive.insert(Type::BooleanLiteral(
+                    new_negative.bool(db) != Truthiness::AlwaysTrue,
+                ));
             }
             _ => {
                 let mut to_remove = SmallVec::<[usize; 1]>::new();
@@ -380,7 +389,7 @@ mod tests {
     use super::{IntersectionBuilder, IntersectionType, Type, UnionType};
 
     use crate::db::tests::{setup_db, TestDb};
-    use crate::types::{global_symbol, todo_type, KnownClass, UnionBuilder};
+    use crate::types::{global_symbol, todo_type, KnownClass, Truthiness, UnionBuilder};
 
     use ruff_db::files::system_path_to_file;
     use ruff_db::system::DbWithTestSystem;
@@ -997,42 +1006,43 @@ mod tests {
         assert_eq!(ty, expected);
     }
 
-    #[test_case(true)]
-    #[test_case(false)]
-    fn build_intersection_simplify_split_bool(bool_value: bool) {
+    #[test_case(Type::BooleanLiteral(true))]
+    #[test_case(Type::BooleanLiteral(false))]
+    #[test_case(Type::AlwaysTruthy)]
+    #[test_case(Type::AlwaysFalsy)]
+    fn build_intersection_simplify_split_bool(t_splitter: Type) {
         let db = setup_db();
-
-        let t_bool = KnownClass::Bool.to_instance(&db);
-        let t_boolean_literal = Type::BooleanLiteral(bool_value);
+        let bool_value = t_splitter.bool(&db) == Truthiness::AlwaysTrue;
 
         // We add t_object in various orders (in first or second position) in
         // the tests below to ensure that the boolean simplification eliminates
         // everything from the intersection, not just `bool`.
         let t_object = KnownClass::Object.to_instance(&db);
+        let t_bool = KnownClass::Bool.to_instance(&db);
 
         let ty = IntersectionBuilder::new(&db)
             .add_positive(t_object)
             .add_positive(t_bool)
-            .add_negative(t_boolean_literal)
+            .add_negative(t_splitter)
             .build();
         assert_eq!(ty, Type::BooleanLiteral(!bool_value));
 
         let ty = IntersectionBuilder::new(&db)
             .add_positive(t_bool)
             .add_positive(t_object)
-            .add_negative(t_boolean_literal)
+            .add_negative(t_splitter)
             .build();
         assert_eq!(ty, Type::BooleanLiteral(!bool_value));
 
         let ty = IntersectionBuilder::new(&db)
             .add_positive(t_object)
-            .add_negative(t_boolean_literal)
+            .add_negative(t_splitter)
             .add_positive(t_bool)
             .build();
         assert_eq!(ty, Type::BooleanLiteral(!bool_value));
 
         let ty = IntersectionBuilder::new(&db)
-            .add_negative(t_boolean_literal)
+            .add_negative(t_splitter)
             .add_positive(t_object)
             .add_positive(t_bool)
             .build();

crates/red_knot_python_semantic/src/types/class_base.rs

@@ -70,7 +70,9 @@ impl<'db> ClassBase<'db> {
             | Type::Tuple(_)
             | Type::SliceLiteral(_)
             | Type::ModuleLiteral(_)
-            | Type::SubclassOf(_) => None,
+            | Type::SubclassOf(_)
+            | Type::AlwaysFalsy
+            | Type::AlwaysTruthy => None,
             Type::KnownInstance(known_instance) => match known_instance {
                 KnownInstanceType::TypeVar(_)
                 | KnownInstanceType::TypeAliasType(_)
@@ -112,15 +114,24 @@ impl<'db> ClassBase<'db> {
                 KnownInstanceType::FrozenSet => {
                     Self::try_from_ty(db, KnownClass::FrozenSet.to_class_literal(db))
                 }
-                KnownInstanceType::Callable
-                | KnownInstanceType::ChainMap
-                | KnownInstanceType::Counter
-                | KnownInstanceType::DefaultDict
-                | KnownInstanceType::Deque
-                | KnownInstanceType::OrderedDict => Self::try_from_ty(
-                    db,
-                    todo_type!("Support for more typing aliases as base classes"),
-                ),
+                KnownInstanceType::ChainMap => {
+                    Self::try_from_ty(db, KnownClass::ChainMap.to_class_literal(db))
+                }
+                KnownInstanceType::Counter => {
+                    Self::try_from_ty(db, KnownClass::Counter.to_class_literal(db))
+                }
+                KnownInstanceType::DefaultDict => {
+                    Self::try_from_ty(db, KnownClass::DefaultDict.to_class_literal(db))
+                }
+                KnownInstanceType::Deque => {
+                    Self::try_from_ty(db, KnownClass::Deque.to_class_literal(db))
+                }
+                KnownInstanceType::OrderedDict => {
+                    Self::try_from_ty(db, KnownClass::OrderedDict.to_class_literal(db))
+                }
+                KnownInstanceType::Callable => {
+                    Self::try_from_ty(db, todo_type!("Support for Callable as a base class"))
+                }
             },
         }
     }

crates/red_knot_python_semantic/src/types/display.rs

@@ -79,8 +79,8 @@ impl Display for DisplayRepresentation<'_> {
             // `[Type::Todo]`'s display should be explicit that is not a valid display of
             // any other type
             Type::Todo(todo) => write!(f, "@Todo{todo}"),
-            Type::ModuleLiteral(file) => {
-                write!(f, "<module '{:?}'>", file.path(self.db))
+            Type::ModuleLiteral(module) => {
+                write!(f, "<module '{}'>", module.module(self.db).name())
             }
             // TODO functions and classes should display using a fully qualified name
             Type::ClassLiteral(ClassLiteralType { class }) => f.write_str(class.name(self.db)),
@@ -140,6 +140,8 @@ impl Display for DisplayRepresentation<'_> {
                 }
                 f.write_str("]")
             }
+            Type::AlwaysTruthy => f.write_str("AlwaysTruthy"),
+            Type::AlwaysFalsy => f.write_str("AlwaysFalsy"),
         }
     }
 }

crates/red_knot_python_semantic/src/types/infer.rs

@@ -124,7 +124,6 @@ pub(crate) fn infer_definition_types<'db>(
     let file = definition.file(db);
     let _span = tracing::trace_span!(
         "infer_definition_types",
-        definition = ?definition.as_id(),
         range = ?definition.kind(db).range(),
         file = %file.path(db)
     )
@@ -866,6 +865,14 @@ impl<'db> TypeInferenceBuilder<'db> {
         self.types.bindings.insert(definition, inferred_ty);
     }
 
+    fn add_unknown_declaration_with_binding(
+        &mut self,
+        node: AnyNodeRef,
+        definition: Definition<'db>,
+    ) {
+        self.add_declaration_with_binding(node, definition, Type::Unknown, Type::Unknown);
+    }
+
     fn infer_module(&mut self, module: &ast::ModModule) {
         self.infer_body(&module.body);
     }
@@ -2116,22 +2123,45 @@ impl<'db> TypeInferenceBuilder<'db> {
         let ast::Alias {
             range: _,
             name,
-            asname: _,
+            asname,
         } = alias;
 
-        let module_ty = if let Some(module_name) = ModuleName::new(name) {
-            if let Some(module) = self.module_ty_from_name(&module_name) {
-                module
-            } else {
-                self.diagnostics.add_unresolved_module(alias, 0, Some(name));
-                Type::Unknown
-            }
-        } else {
+        // The name of the module being imported
+        let Some(full_module_name) = ModuleName::new(name) else {
             tracing::debug!("Failed to resolve import due to invalid syntax");
-            Type::Unknown
+            self.add_unknown_declaration_with_binding(alias.into(), definition);
+            return;
         };
 
-        self.add_declaration_with_binding(alias.into(), definition, module_ty, module_ty);
+        // Resolve the module being imported.
+        let Some(full_module_ty) = self.module_ty_from_name(&full_module_name) else {
+            self.diagnostics.add_unresolved_module(alias, 0, Some(name));
+            self.add_unknown_declaration_with_binding(alias.into(), definition);
+            return;
+        };
+
+        let binding_ty = if asname.is_some() {
+            // If we are renaming the imported module via an `as` clause, then we bind the resolved
+            // module's type to that name, even if that module is nested.
+            full_module_ty
+        } else if full_module_name.contains('.') {
+            // If there's no `as` clause and the imported module is nested, we're not going to bind
+            // the resolved module itself into the current scope; we're going to bind the top-most
+            // parent package of that module.
+            let topmost_parent_name =
+                ModuleName::new(full_module_name.components().next().unwrap()).unwrap();
+            let Some(topmost_parent_ty) = self.module_ty_from_name(&topmost_parent_name) else {
+                self.add_unknown_declaration_with_binding(alias.into(), definition);
+                return;
+            };
+            topmost_parent_ty
+        } else {
+            // If there's no `as` clause and the imported module isn't nested, then the imported
+            // module _is_ what we bind into the current scope.
+            full_module_ty
+        };
+
+        self.add_declaration_with_binding(alias.into(), definition, binding_ty, binding_ty);
     }
 
     fn infer_import_from_statement(&mut self, import: &ast::StmtImportFrom) {
@@ -2211,12 +2241,6 @@ impl<'db> TypeInferenceBuilder<'db> {
         // TODO:
         // - Absolute `*` imports (`from collections import *`)
         // - Relative `*` imports (`from ...foo import *`)
-        // - Submodule imports (`from collections import abc`,
-        //   where `abc` is a submodule of the `collections` package)
-        //
-        // For the last item, see the currently skipped tests
-        // `follow_relative_import_bare_to_module()` and
-        // `follow_nonexistent_import_bare_to_module()`.
         let ast::StmtImportFrom { module, level, .. } = import_from;
         let module = module.as_deref();
 
@@ -2239,46 +2263,13 @@ impl<'db> TypeInferenceBuilder<'db> {
                 .ok_or(ModuleNameResolutionError::InvalidSyntax)
         };
 
-        let ty = match module_name {
-            Ok(module_name) => {
-                if let Some(module_ty) = self.module_ty_from_name(&module_name) {
-                    let ast::Alias {
-                        range: _,
-                        name,
-                        asname: _,
-                    } = alias;
-
-                    match module_ty.member(self.db, &ast::name::Name::new(&name.id)) {
-                        Symbol::Type(ty, boundness) => {
-                            if boundness == Boundness::PossiblyUnbound {
-                                self.diagnostics.add_lint(
-                                    &POSSIBLY_UNBOUND_IMPORT,
-                                    AnyNodeRef::Alias(alias),
-                                    format_args!("Member `{name}` of module `{module_name}` is possibly unbound", ),
-                                );
-                            }
-
-                            ty
-                        }
-                        Symbol::Unbound => {
-                            self.diagnostics.add_lint(
-                                &UNRESOLVED_IMPORT,
-                                AnyNodeRef::Alias(alias),
-                                format_args!("Module `{module_name}` has no member `{name}`",),
-                            );
-                            Type::Unknown
-                        }
-                    }
-                } else {
-                    self.diagnostics
-                        .add_unresolved_module(import_from, *level, module);
-                    Type::Unknown
-                }
-            }
+        let module_name = match module_name {
+            Ok(module_name) => module_name,
             Err(ModuleNameResolutionError::InvalidSyntax) => {
                 tracing::debug!("Failed to resolve import due to invalid syntax");
                 // Invalid syntax diagnostics are emitted elsewhere.
-                Type::Unknown
+                self.add_unknown_declaration_with_binding(alias.into(), definition);
+                return;
             }
             Err(ModuleNameResolutionError::TooManyDots) => {
                 tracing::debug!(
@@ -2287,7 +2278,8 @@ impl<'db> TypeInferenceBuilder<'db> {
                 );
                 self.diagnostics
                     .add_unresolved_module(import_from, *level, module);
-                Type::Unknown
+                self.add_unknown_declaration_with_binding(alias.into(), definition);
+                return;
             }
             Err(ModuleNameResolutionError::UnknownCurrentModule) => {
                 tracing::debug!(
@@ -2297,10 +2289,72 @@ impl<'db> TypeInferenceBuilder<'db> {
                 );
                 self.diagnostics
                     .add_unresolved_module(import_from, *level, module);
-                Type::Unknown
+                self.add_unknown_declaration_with_binding(alias.into(), definition);
+                return;
             }
         };
 
+        let Some(module_ty) = self.module_ty_from_name(&module_name) else {
+            self.diagnostics
+                .add_unresolved_module(import_from, *level, module);
+            self.add_unknown_declaration_with_binding(alias.into(), definition);
+            return;
+        };
+
+        let ast::Alias {
+            range: _,
+            name,
+            asname: _,
+        } = alias;
+
+        // Check if the symbol being imported is a submodule.  This won't get handled by the
+        // `Type::member` call below because it relies on the semantic index's `imported_modules`
+        // set.  The semantic index does not include information about `from...import` statements
+        // because there are two things it cannot determine while only inspecting the content of
+        // the current file:
+        //
+        //   - whether the imported symbol is an attribute or submodule
+        //   - whether the containing file is in a module or a package (needed to correctly resolve
+        //     relative imports)
+        //
+        // The first would be solvable by making it a _potentially_ imported modules set.  The
+        // second is not.
+        //
+        // Regardless, for now, we sidestep all of that by repeating the submodule-or-attribute
+        // check here when inferring types for a `from...import` statement.
+        if let Some(submodule_name) = ModuleName::new(name) {
+            let mut full_submodule_name = module_name.clone();
+            full_submodule_name.extend(&submodule_name);
+            if let Some(submodule_ty) = self.module_ty_from_name(&full_submodule_name) {
+                self.add_declaration_with_binding(
+                    alias.into(),
+                    definition,
+                    submodule_ty,
+                    submodule_ty,
+                );
+                return;
+            }
+        }
+
+        // Otherwise load the requested attribute from the module.
+        let Symbol::Type(ty, boundness) = module_ty.member(self.db, name) else {
+            self.diagnostics.add_lint(
+                &UNRESOLVED_IMPORT,
+                AnyNodeRef::Alias(alias),
+                format_args!("Module `{module_name}` has no member `{name}`",),
+            );
+            self.add_unknown_declaration_with_binding(alias.into(), definition);
+            return;
+        };
+
+        if boundness == Boundness::PossiblyUnbound {
+            self.diagnostics.add_lint(
+                &POSSIBLY_UNBOUND_IMPORT,
+                AnyNodeRef::Alias(alias),
+                format_args!("Member `{name}` of module `{module_name}` is possibly unbound",),
+            );
+        }
+
         self.add_declaration_with_binding(alias.into(), definition, ty, ty);
     }
 
@@ -2316,7 +2370,8 @@ impl<'db> TypeInferenceBuilder<'db> {
     }
 
     fn module_ty_from_name(&self, module_name: &ModuleName) -> Option<Type<'db>> {
-        resolve_module(self.db, module_name).map(|module| Type::ModuleLiteral(module.file()))
+        resolve_module(self.db, module_name)
+            .map(|module| Type::module_literal(self.db, self.file, module))
     }
 
     fn infer_decorator(&mut self, decorator: &ast::Decorator) -> Type<'db> {
@@ -4904,42 +4959,45 @@ impl<'db> TypeInferenceBuilder<'db> {
                 self.infer_type_expression(arguments_slice);
                 todo_type!("Callable types")
             }
+
+            // TODO: Generics
             KnownInstanceType::ChainMap => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.ChainMap alias")
+                KnownClass::ChainMap.to_instance(self.db)
             }
             KnownInstanceType::OrderedDict => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.OrderedDict alias")
+                KnownClass::OrderedDict.to_instance(self.db)
             }
             KnownInstanceType::Dict => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.Dict alias")
+                KnownClass::Dict.to_instance(self.db)
             }
             KnownInstanceType::List => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.List alias")
+                KnownClass::List.to_instance(self.db)
             }
             KnownInstanceType::DefaultDict => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.DefaultDict[] alias")
+                KnownClass::DefaultDict.to_instance(self.db)
             }
             KnownInstanceType::Counter => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.Counter[] alias")
+                KnownClass::Counter.to_instance(self.db)
             }
             KnownInstanceType::Set => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.Set alias")
+                KnownClass::Set.to_instance(self.db)
             }
             KnownInstanceType::FrozenSet => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.FrozenSet alias")
+                KnownClass::FrozenSet.to_instance(self.db)
             }
             KnownInstanceType::Deque => {
                 self.infer_type_expression(arguments_slice);
-                todo_type!("typing.Deque alias")
+                KnownClass::Deque.to_instance(self.db)
             }
+
             KnownInstanceType::ReadOnly => {
                 self.infer_type_expression(arguments_slice);
                 todo_type!("Required[] type qualifier")

crates/red_knot_python_semantic/src/types/narrow.rs

@@ -196,6 +196,7 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
         is_positive: bool,
     ) -> Option<NarrowingConstraints<'db>> {
         match expression_node {
+            ast::Expr::Name(name) => Some(self.evaluate_expr_name(name, is_positive)),
             ast::Expr::Compare(expr_compare) => {
                 self.evaluate_expr_compare(expr_compare, expression, is_positive)
             }
@@ -254,6 +255,31 @@ impl<'db> NarrowingConstraintsBuilder<'db> {
         }
     }
 
+    fn evaluate_expr_name(
+        &mut self,
+        expr_name: &ast::ExprName,
+        is_positive: bool,
+    ) -> NarrowingConstraints<'db> {
+        let ast::ExprName { id, .. } = expr_name;
+
+        let symbol = self
+            .symbols()
+            .symbol_id_by_name(id)
+            .expect("Should always have a symbol for every Name node");
+        let mut constraints = NarrowingConstraints::default();
+
+        constraints.insert(
+            symbol,
+            if is_positive {
+                Type::AlwaysFalsy.negate(self.db)
+            } else {
+                Type::AlwaysTruthy.negate(self.db)
+            },
+        );
+
+        constraints
+    }
+
     fn evaluate_expr_compare(
         &mut self,
         expr_compare: &ast::ExprCompare,

crates/red_knot_python_semantic/src/types/property_tests.rs

@@ -75,6 +75,8 @@ fn arbitrary_core_type(g: &mut Gen) -> Ty {
         Ty::AbcClassLiteral("ABCMeta"),
         Ty::SubclassOfAbcClass("ABC"),
         Ty::SubclassOfAbcClass("ABCMeta"),
+        Ty::AlwaysTruthy,
+        Ty::AlwaysFalsy,
     ])
     .unwrap()
     .clone()

crates/red_knot_server/src/server/api.rs

@@ -91,11 +91,11 @@ fn background_request_task<'a, R: traits::BackgroundDocumentRequestHandler>(
         let db = match path {
             AnySystemPath::System(path) => {
                 match session.workspace_db_for_path(path.as_std_path()) {
-                    Some(db) => db.snapshot(),
-                    None => session.default_workspace_db().snapshot(),
+                    Some(db) => db.clone(),
+                    None => session.default_workspace_db().clone(),
                 }
             }
-            AnySystemPath::SystemVirtual(_) => session.default_workspace_db().snapshot(),
+            AnySystemPath::SystemVirtual(_) => session.default_workspace_db().clone(),
         };
 
         let Some(snapshot) = session.take_snapshot(url) else {

crates/red_knot_test/src/db.rs

@@ -9,6 +9,7 @@ use ruff_db::vendored::VendoredFileSystem;
 use ruff_db::{Db as SourceDb, Upcast};
 
 #[salsa::db]
+#[derive(Clone)]
 pub(crate) struct Db {
     workspace_root: SystemPathBuf,
     storage: salsa::Storage<Self>,

crates/red_knot_workspace/src/db.rs

@@ -21,6 +21,7 @@ pub trait Db: SemanticDb + Upcast<dyn SemanticDb> {
 }
 
 #[salsa::db]
+#[derive(Clone)]
 pub struct RootDatabase {
     workspace: Option<Workspace>,
     storage: salsa::Storage<RootDatabase>,
@@ -80,17 +81,6 @@ impl RootDatabase {
     {
         Cancelled::catch(|| f(self))
     }
-
-    #[must_use]
-    pub fn snapshot(&self) -> Self {
-        Self {
-            workspace: self.workspace,
-            storage: self.storage.clone(),
-            files: self.files.snapshot(),
-            system: Arc::clone(&self.system),
-            rule_selection: Arc::clone(&self.rule_selection),
-        }
-    }
 }
 
 impl Upcast<dyn SemanticDb> for RootDatabase {
@@ -184,6 +174,7 @@ pub(crate) mod tests {
     use crate::DEFAULT_LINT_REGISTRY;
 
     #[salsa::db]
+    #[derive(Clone)]
     pub(crate) struct TestDb {
         storage: salsa::Storage<Self>,
         events: Arc<std::sync::Mutex<Vec<Event>>>,

crates/red_knot_workspace/src/workspace.rs

@@ -195,13 +195,13 @@ impl Workspace {
         let result = Arc::new(std::sync::Mutex::new(Vec::new()));
         let inner_result = Arc::clone(&result);
 
-        let db = db.snapshot();
+        let db = db.clone();
         let workspace_span = workspace_span.clone();
 
         rayon::scope(move |scope| {
             for file in &files {
                 let result = inner_result.clone();
-                let db = db.snapshot();
+                let db = db.clone();
                 let workspace_span = workspace_span.clone();
 
                 scope.spawn(move |_| {

crates/ruff/src/commands/analyze_graph.rs

@@ -81,7 +81,7 @@ pub(crate) fn analyze_graph(
         // Collect and resolve the imports for each file.
         let result = Arc::new(Mutex::new(Vec::new()));
         let inner_result = Arc::clone(&result);
-        let db = db.snapshot();
+        let db = db.clone();
 
         rayon::scope(move |scope| {
             for resolved_file in paths {
@@ -137,7 +137,7 @@ pub(crate) fn analyze_graph(
                     continue;
                 };
 
-                let db = db.snapshot();
+                let db = db.clone();
                 let glob_resolver = glob_resolver.clone();
                 let root = root.clone();
                 let result = inner_result.clone();

crates/ruff_benchmark/benches/red_knot.rs

@@ -31,15 +31,10 @@ static EXPECTED_DIAGNOSTICS: &[&str] = &[
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:98:12 Name `char` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:101:12 Name `char` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:104:14 Name `char` used when possibly not defined",
-    "error[lint:conflicting-declarations] /src/tomllib/_parser.py:108:17 Conflicting declared types for `second_char`: Unknown, str | None",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:115:14 Name `char` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:126:12 Name `char` used when possibly not defined",
-    "error[lint:conflicting-declarations] /src/tomllib/_parser.py:267:9 Conflicting declared types for `char`: Unknown, str | None",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:348:20 Name `nest` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:353:5 Name `nest` used when possibly not defined",
-    "error[lint:conflicting-declarations] /src/tomllib/_parser.py:364:9 Conflicting declared types for `char`: Unknown, str | None",
-    "error[lint:conflicting-declarations] /src/tomllib/_parser.py:381:13 Conflicting declared types for `char`: Unknown, str | None",
-    "error[lint:conflicting-declarations] /src/tomllib/_parser.py:395:9 Conflicting declared types for `char`: Unknown, str | None",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:453:24 Name `nest` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:455:9 Name `nest` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:482:16 Name `char` used when possibly not defined",
@@ -47,7 +42,6 @@ static EXPECTED_DIAGNOSTICS: &[&str] = &[
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:573:12 Name `char` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:579:12 Name `char` used when possibly not defined",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:580:63 Name `char` used when possibly not defined",
-    "error[lint:conflicting-declarations] /src/tomllib/_parser.py:590:9 Conflicting declared types for `char`: Unknown, str | None",
     "warning[lint:possibly-unresolved-reference] /src/tomllib/_parser.py:629:38 Name `datetime_obj` used when possibly not defined",
 ];
 

crates/ruff_db/src/files.rs

@@ -48,7 +48,7 @@ pub fn vendored_path_to_file(
 }
 
 /// Lookup table that maps [file paths](`FilePath`) to salsa interned [`File`] instances.
-#[derive(Default)]
+#[derive(Default, Clone)]
 pub struct Files {
     inner: Arc<FilesInner>,
 }
@@ -253,13 +253,6 @@ impl Files {
             root.set_revision(db).to(FileRevision::now());
         }
     }
-
-    #[must_use]
-    pub fn snapshot(&self) -> Self {
-        Self {
-            inner: Arc::clone(&self.inner),
-        }
-    }
 }
 
 impl std::fmt::Debug for Files {

crates/ruff_db/src/lib.rs

@@ -48,13 +48,13 @@ mod tests {
     ///
     /// Uses an in memory filesystem and it stubs out the vendored files by default.
     #[salsa::db]
-    #[derive(Default)]
+    #[derive(Default, Clone)]
     pub(crate) struct TestDb {
         storage: salsa::Storage<Self>,
         files: Files,
         system: TestSystem,
         vendored: VendoredFileSystem,
-        events: std::sync::Arc<std::sync::Mutex<Vec<salsa::Event>>>,
+        events: Arc<std::sync::Mutex<Vec<salsa::Event>>>,
     }
 
     impl TestDb {

crates/ruff_db/src/system/test.rs

@@ -175,19 +175,26 @@ pub trait DbWithTestSystem: Db + Sized {
     ///
     /// # Panics
     /// If the system isn't using the memory file system.
-    fn write_file(
-        &mut self,
-        path: impl AsRef<SystemPath>,
-        content: impl ToString,
-    ) -> crate::system::Result<()> {
+    fn write_file(&mut self, path: impl AsRef<SystemPath>, content: impl ToString) -> Result<()> {
         let path = path.as_ref();
-        let result = self
-            .test_system()
-            .memory_file_system()
-            .write_file(path, content);
+
+        let memory_fs = self.test_system().memory_file_system();
+
+        let sync_ancestors = path
+            .parent()
+            .is_some_and(|parent| !memory_fs.exists(parent));
+        let result = memory_fs.write_file(path, content);
 
         if result.is_ok() {
             File::sync_path(self, path);
+
+            // Sync the ancestor paths if the path's parent
+            // directory didn't exist before.
+            if sync_ancestors {
+                for ancestor in path.ancestors() {
+                    File::sync_path(self, ancestor);
+                }
+            }
         }
 
         result

crates/ruff_graph/src/db.rs

@@ -16,7 +16,7 @@ static EMPTY_VENDORED: std::sync::LazyLock<VendoredFileSystem> = std::sync::Lazy
 });
 
 #[salsa::db]
-#[derive(Default)]
+#[derive(Default, Clone)]
 pub struct ModuleDb {
     storage: salsa::Storage<Self>,
     files: Files,
@@ -55,17 +55,6 @@ impl ModuleDb {
 
         Ok(db)
     }
-
-    /// Create a snapshot of the current database.
-    #[must_use]
-    pub fn snapshot(&self) -> Self {
-        Self {
-            storage: self.storage.clone(),
-            system: self.system.clone(),
-            files: self.files.snapshot(),
-            rule_selection: Arc::clone(&self.rule_selection),
-        }
-    }
 }
 
 impl Upcast<dyn SourceDb> for ModuleDb {

crates/ruff_linter/resources/test/fixtures/airflow/AIR302_names.py

@@ -1,36 +1,80 @@
-from airflow import PY36, PY37, PY38, PY39, PY310, PY311, PY312
-from airflow.triggers.external_task import TaskStateTrigger
-from airflow.api_connexion.security import requires_access
+from airflow import (
+    PY36,
+    PY37,
+    PY38,
+    PY39,
+    PY310,
+    PY311,
+    PY312,
+    Dataset as DatasetFromRoot,
+)
+from airflow.api_connexion.security import requires_access, requires_access_dataset
+from airflow.auth.managers.base_auth_manager import is_authorized_dataset
+from airflow.auth.managers.models.resource_details import DatasetDetails
 from airflow.configuration import (
+    as_dict,
     get,
     getboolean,
     getfloat,
     getint,
     has_option,
     remove_option,
-    as_dict,
     set,
 )
 from airflow.contrib.aws_athena_hook import AWSAthenaHook
-from airflow.metrics.validators import AllowListValidator
-from airflow.metrics.validators import BlockListValidator
-from airflow.operators.subdag import SubDagOperator
-from airflow.sensors.external_task import ExternalTaskSensorLink
+from airflow.datasets import (
+    Dataset,
+    DatasetAlias,
+    DatasetAliasEvent,
+    DatasetAll,
+    DatasetAny,
+    expand_alias_to_datasets,
+)
+from airflow.datasets.metadata import Metadata
+from airflow.datasets.manager import (
+    DatasetManager,
+    dataset_manager,
+    resolve_dataset_manager,
+)
+from airflow.lineage.hook import DatasetLineageInfo
+from airflow.listeners.spec.dataset import on_dataset_changed, on_dataset_created
+from airflow.metrics.validators import AllowListValidator, BlockListValidator
+from airflow.operators import dummy_operator
 from airflow.operators.bash_operator import BashOperator
 from airflow.operators.branch_operator import BaseBranchOperator
-from airflow.operators.dummy import EmptyOperator, DummyOperator
-from airflow.operators import dummy_operator
+from airflow.operators.dummy import DummyOperator, EmptyOperator
 from airflow.operators.email_operator import EmailOperator
+from airflow.operators.subdag import SubDagOperator
+from airflow.providers.amazon.auth_manager.avp.entities import AvpEntities
+from airflow.providers.amazon.aws.datasets import s3
+from airflow.providers.common.io.datasets import file as common_io_file
+from airflow.providers.fab.auth_manager import fab_auth_manager
+from airflow.providers.google.datasets import bigquery, gcs
+from airflow.providers.mysql.datasets import mysql
+from airflow.providers.openlineage.utils.utils import (
+    DatasetInfo,
+    translate_airflow_dataset,
+)
+from airflow.providers.postgres.datasets import postgres
+from airflow.providers.trino.datasets import trino
+from airflow.secrets.local_filesystem import get_connection, load_connections
+from airflow.security.permissions import RESOURCE_DATASET
 from airflow.sensors.base_sensor_operator import BaseSensorOperator
 from airflow.sensors.date_time_sensor import DateTimeSensor
+from airflow.sensors.external_task import (
+    ExternalTaskSensorLink as ExternalTaskSensorLinkFromExternalTask,
+)
 from airflow.sensors.external_task_sensor import (
     ExternalTaskMarker,
     ExternalTaskSensor,
-    ExternalTaskSensorLink,
+    ExternalTaskSensorLink as ExternalTaskSensorLinkFromExternalTaskSensor,
 )
 from airflow.sensors.time_delta_sensor import TimeDeltaSensor
-from airflow.secrets.local_filesystem import get_connection, load_connections
+from airflow.timetables.datasets import DatasetOrTimeSchedule
+from airflow.timetables.simple import DatasetTriggeredTimetable
+from airflow.triggers.external_task import TaskStateTrigger
 from airflow.utils import dates
+from airflow.utils.dag_cycle_tester import test_cycle
 from airflow.utils.dates import (
     date_range,
     datetime_to_nano,
@@ -44,70 +88,168 @@ from airflow.utils.decorators import apply_defaults
 from airflow.utils.file import TemporaryDirectory, mkdirs
 from airflow.utils.helpers import chain, cross_downstream
 from airflow.utils.state import SHUTDOWN, terminating_states
-from airflow.utils.dag_cycle_tester import test_cycle
 from airflow.utils.trigger_rule import TriggerRule
-from airflow.www.auth import has_access
+from airflow.www.auth import has_access, has_access_dataset
 from airflow.www.utils import get_sensitive_variables_fields, should_hide_value_for_key
 
+# airflow root
 PY36, PY37, PY38, PY39, PY310, PY311, PY312
+DatasetFromRoot
 
+# airflow.api_connexion.security
+requires_access, requires_access_dataset
+
+# airflow.auth.managers
+is_authorized_dataset
+DatasetDetails
+
+# airflow.configuration
+get, getboolean, getfloat, getint, has_option, remove_option, as_dict, set
+
+
+# airflow.contrib.*
 AWSAthenaHook
-TaskStateTrigger
 
-requires_access
+# airflow.datasets
+Dataset
+DatasetAlias
+DatasetAliasEvent
+DatasetAll
+DatasetAny
+expand_alias_to_datasets
+Metadata
 
-AllowListValidator
-BlockListValidator
+# airflow.datasets.manager
+DatasetManager, dataset_manager, resolve_dataset_manager
 
+# airflow.lineage.hook
+DatasetLineageInfo
+
+# airflow.listeners.spec.dataset
+on_dataset_changed, on_dataset_created
+
+# airflow.metrics.validators
+AllowListValidator, BlockListValidator
+
+# airflow.operators.dummy_operator
+dummy_operator.EmptyOperator
+dummy_operator.DummyOperator
+
+# airflow.operators.bash_operator
+BashOperator
+
+# airflow.operators.branch_operator
+BaseBranchOperator
+
+# airflow.operators.dummy
+EmptyOperator, DummyOperator
+
+# airflow.operators.email_operator
+EmailOperator
+
+# airflow.operators.subdag.*
 SubDagOperator
 
+# airflow.providers.amazon
+AvpEntities.DATASET
+s3.create_dataset
+s3.convert_dataset_to_openlineage
+s3.sanitize_uri
+
+# airflow.providers.common.io
+common_io_file.convert_dataset_to_openlineage
+common_io_file.create_dataset
+common_io_file.sanitize_uri
+
+# airflow.providers.fab
+fab_auth_manager.is_authorized_dataset
+
+# airflow.providers.google
+bigquery.sanitize_uri
+
+gcs.create_dataset
+gcs.sanitize_uri
+gcs.convert_dataset_to_openlineage
+
+# airflow.providers.mysql
+mysql.sanitize_uri
+
+# airflow.providers.openlineage
+DatasetInfo, translate_airflow_dataset
+
+# airflow.providers.postgres
+postgres.sanitize_uri
+
+# airflow.providers.trino
+trino.sanitize_uri
+
+# airflow.secrets
+get_connection, load_connections
+
+# airflow.security.permissions
+RESOURCE_DATASET
+
+# airflow.sensors.base_sensor_operator
+BaseSensorOperator
+
+# airflow.sensors.date_time_sensor
+DateTimeSensor
+
+# airflow.sensors.external_task
+ExternalTaskSensorLinkFromExternalTask
+
+# airflow.sensors.external_task_sensor
+ExternalTaskMarker
+ExternalTaskSensor
+ExternalTaskSensorLinkFromExternalTaskSensor
+
+# airflow.sensors.time_delta_sensor
+TimeDeltaSensor
+
+# airflow.timetables
+DatasetOrTimeSchedule
+DatasetTriggeredTimetable
+
+# airflow.triggers.external_task
+TaskStateTrigger
+
+# airflow.utils.date
 dates.date_range
 dates.days_ago
 
 date_range
 days_ago
+infer_time_unit
 parse_execution_date
 round_time
 scale_time_units
-infer_time_unit
-
 
 # This one was not deprecated.
 datetime_to_nano
 dates.datetime_to_nano
 
-get, getboolean, getfloat, getint, has_option, remove_option, as_dict, set
-
-get_connection, load_connections
-
-
-ExternalTaskSensorLink
-BashOperator
-BaseBranchOperator
-EmptyOperator, DummyOperator
-dummy_operator.EmptyOperator
-dummy_operator.DummyOperator
-EmailOperator
-BaseSensorOperator
-DateTimeSensor
-(ExternalTaskMarker, ExternalTaskSensor, ExternalTaskSensorLink)
-TimeDeltaSensor
+# airflow.utils.dag_cycle_tester
+test_cycle
 
+# airflow.utils.decorators
 apply_defaults
 
-TemporaryDirectory
-mkdirs
+# airflow.utils.file
+TemporaryDirectory, mkdirs
 
-chain
-cross_downstream
+#  airflow.utils.helpers
+chain, cross_downstream
 
-SHUTDOWN
-terminating_states
+# airflow.utils.state
+SHUTDOWN, terminating_states
 
+#  airflow.utils.trigger_rule
 TriggerRule.DUMMY
 TriggerRule.NONE_FAILED_OR_SKIPPED
 
-test_cycle
-
+# airflow.www.auth
 has_access
+has_access_dataset
+
+# airflow.www.utils
 get_sensitive_variables_fields, should_hide_value_for_key

crates/ruff_linter/resources/test/fixtures/perflint/PERF401.py

@@ -244,3 +244,10 @@ def f():
         for a in values:
             result.append(a + 1)  # PERF401
     result = []
+
+def f():
+    values = [1, 2, 3]
+    result = []
+    for i in values:
+        result.append(i + 1)  # Ok
+    del i

crates/ruff_linter/resources/test/fixtures/pydocstyle/D403.py

@@ -31,3 +31,13 @@ def single_word():
 
 def single_word_no_dot():
     """singleword"""
+
+def first_word_lots_of_whitespace():
+    """
+
+
+
+    here is the start of my docstring!
+
+    What do you think?    
+    """

crates/ruff_linter/resources/test/fixtures/pylint/non_augmented_assignment.py

@@ -50,6 +50,50 @@ class T:
 obj = T()
 obj.a = obj.a + 1
 
+
+a = a+-1
+
+# Regression tests for https://github.com/astral-sh/ruff/issues/11672
+test = 0x5
+test = test + 0xBA
+
+test2 = b""
+test2 = test2 + b"\000"
+
+test3 = ""
+test3 = test3 + (   a := R""
+                         f"oo"   )
+
+test4 = []
+test4 = test4 + ( e
+                  for e in
+                  range(10)
+                  )
+
+test5 = test5 + (
+    4
+    *
+    10
+)
+
+test6 = test6 + \
+        (
+            4
+            *
+            10
+        )
+
+test7 = \
+        100 \
+    + test7
+
+test8 = \
+    886 \
+    + \
+ \
+    test8
+
+
 # OK
 a_list[0] = a_list[:] * 3
 index = a_number = a_number + 1

crates/ruff_linter/src/checkers/ast/analyze/definitions.rs

@@ -46,7 +46,7 @@ pub(crate) fn definitions(checker: &mut Checker) {
         Rule::EndsInPeriod,
         Rule::EndsInPunctuation,
         Rule::EscapeSequenceInDocstring,
-        Rule::FirstLineCapitalized,
+        Rule::FirstWordUncapitalized,
         Rule::FitsOnOneLine,
         Rule::IndentWithSpaces,
         Rule::MultiLineSummaryFirstLine,
@@ -277,7 +277,7 @@ pub(crate) fn definitions(checker: &mut Checker) {
             if checker.enabled(Rule::NoSignature) {
                 pydocstyle::rules::no_signature(checker, &docstring);
             }
-            if checker.enabled(Rule::FirstLineCapitalized) {
+            if checker.enabled(Rule::FirstWordUncapitalized) {
                 pydocstyle::rules::capitalized(checker, &docstring);
             }
             if checker.enabled(Rule::DocstringStartsWithThis) {

crates/ruff_linter/src/codes.rs

@@ -566,7 +566,7 @@ pub fn code_to_rule(linter: Linter, code: &str) -> Option<(RuleGroup, Rule)> {
         (Pydocstyle, "400") => (RuleGroup::Stable, rules::pydocstyle::rules::EndsInPeriod),
         (Pydocstyle, "401") => (RuleGroup::Stable, rules::pydocstyle::rules::NonImperativeMood),
         (Pydocstyle, "402") => (RuleGroup::Stable, rules::pydocstyle::rules::NoSignature),
-        (Pydocstyle, "403") => (RuleGroup::Stable, rules::pydocstyle::rules::FirstLineCapitalized),
+        (Pydocstyle, "403") => (RuleGroup::Stable, rules::pydocstyle::rules::FirstWordUncapitalized),
         (Pydocstyle, "404") => (RuleGroup::Stable, rules::pydocstyle::rules::DocstringStartsWithThis),
         (Pydocstyle, "405") => (RuleGroup::Stable, rules::pydocstyle::rules::CapitalizeSectionName),
         (Pydocstyle, "406") => (RuleGroup::Stable, rules::pydocstyle::rules::NewLineAfterSectionName),

crates/ruff_linter/src/rules/airflow/rules/removal_in_3.rs

@@ -160,15 +160,23 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
             .semantic()
             .resolve_qualified_name(expr)
             .and_then(|qualname| match qualname.segments() {
-                ["airflow", "triggers", "external_task", "TaskStateTrigger"] => {
-                    Some((qualname.to_string(), Replacement::None))
-                }
                 ["airflow", "api_connexion", "security", "requires_access"] => Some((
                     qualname.to_string(),
                     Replacement::Name(
                         "airflow.api_connexion.security.requires_access_*".to_string(),
                     ),
                 )),
+                ["airflow", "api_connexion", "security", "requires_access_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.api_connexion.security.requires_access_asset".to_string()),
+                )),
+                ["airflow", "triggers", "external_task", "TaskStateTrigger"] => {
+                    Some((qualname.to_string(), Replacement::None))
+                }
+                ["airflow", "security", "permissions", "RESOURCE_DATASET"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.security.permissions.RESOURCE_ASSET".to_string()),
+                )),
                 // airflow.PY\d{1,2}
                 ["airflow", "PY36"] => Some((
                     qualname.to_string(),
@@ -231,8 +239,22 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
                     qualname.to_string(),
                     Replacement::Name("airflow.configuration.conf.set".to_string()),
                 )),
+                // airflow.auth.managers
+                ["airflow", "auth", "managers", "models", "resource_details", "DatasetDetails"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.auth.managers.models.resource_details.AssetDetails".to_string()),
+                )),
+                ["airflow", "auth", "managers", "base_auth_manager", "is_authorized_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.auth.managers.base_auth_manager.is_authorized_asset".to_string()),
+                )),
                 // airflow.contrib.*
-                ["airflow", "contrib", ..] => Some((qualname.to_string(), Replacement::None)),
+                ["airflow", "contrib", ..] => Some((qualname.to_string(),
+                    Replacement::Message(
+                        "The whole `airflow.contrib` module has been removed."
+                            .to_string(),
+                    ),
+                )),
                 // airflow.metrics.validators
                 ["airflow", "metrics", "validators", "AllowListValidator"] => Some((
                     qualname.to_string(),
@@ -246,13 +268,86 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
                         "airflow.metrics.validators.PatternBlockListValidator".to_string(),
                     ),
                 )),
-                // airflow.operators
-                ["airflow", "operators", "subdag", ..] => {
+                // airflow.datasets
+                ["airflow", "Dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sdk.definitions.asset.Asset".to_string()),
+                )),
+                ["airflow", "datasets", "DatasetAliasEvent"] => {
                     Some((qualname.to_string(), Replacement::None))
                 }
-                ["airflow.sensors.external_task.ExternalTaskSensorLink"] => Some((
+                ["airflow", "datasets", "Dataset"] => Some((
                     qualname.to_string(),
-                    Replacement::Name("airflow.sensors.external_task.ExternalDagLin".to_string()),
+                    Replacement::Name("airflow.sdk.definitions.asset.Asset".to_string()),
+                )),
+                ["airflow", "datasets", "DatasetAlias"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sdk.definitions.asset.AssetAlias".to_string()),
+                )),
+                ["airflow", "datasets", "DatasetAll"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sdk.definitions.asset.AssetAll".to_string()),
+                )),
+                ["airflow", "datasets", "DatasetAny"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sdk.definitions.asset.AssetAny".to_string()),
+                )),
+                ["airflow", "datasets", "expand_alias_to_datasets"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sdk.definitions.asset.expand_alias_to_assets".to_string()),
+                )),
+                ["airflow", "datasets", "metadata", "Metadata"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sdk.definitions.asset.metadata.Metadata".to_string()),
+                )),
+                // airflow.datasets.manager
+                ["airflow", "datasets", "manager", "dataset_manager"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.assets.manager".to_string()),
+                )),
+                ["airflow", "datasets", "manager", "resolve_dataset_manager"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.assets.resolve_asset_manager".to_string()),
+                )),
+                ["airflow", "datasets.manager", "DatasetManager"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.assets.AssetManager".to_string()),
+                )),
+                // airflow.listeners.spec
+                ["airflow", "listeners", "spec", "dataset", "on_dataset_created"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.listeners.spec.asset.on_asset_created".to_string()),
+                )),
+                ["airflow", "listeners", "spec", "dataset", "on_dataset_changed"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.listeners.spec.asset.on_asset_changed".to_string()),
+                )),
+                // airflow.timetables
+                ["airflow", "timetables", "datasets", "DatasetOrTimeSchedule"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.timetables.assets.AssetOrTimeSchedule".to_string()),
+                )),
+                ["airflow", "timetables", "simple", "DatasetTriggeredTimetable"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.timetables.simple.AssetTriggeredTimetable".to_string()),
+                )),
+                // airflow.lineage.hook
+                ["airflow", "lineage", "hook", "DatasetLineageInfo"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.lineage.hook.AssetLineageInfo".to_string()),
+                )),
+                // airflow.operators
+                ["airflow", "operators", "subdag", ..] => {
+                    Some((
+                        qualname.to_string(),
+                        Replacement::Message(
+                            "The whole `airflow.subdag` module has been removed.".to_string(),
+                        ),
+                    ))
+                },
+                ["airflow", "sensors", "external_task", "ExternalTaskSensorLink"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.sensors.external_task.ExternalDagLink".to_string()),
                 )),
                 ["airflow", "operators", "bash_operator", "BashOperator"] => Some((
                     qualname.to_string(),
@@ -305,7 +400,7 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
                 ["airflow", "sensors", "external_task_sensor", "ExternalTaskSensorLink"] => Some((
                     qualname.to_string(),
                     Replacement::Name(
-                        "airflow.sensors.external_task.ExternalTaskSensorLink".to_string(),
+                        "airflow.sensors.external_task.ExternalDagLink".to_string(),
                     ),
                 )),
                 ["airflow", "sensors", "time_delta_sensor", "TimeDeltaSensor"] => Some((
@@ -354,7 +449,6 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
                     qualname.to_string(),
                     Replacement::Name("pendulum.today('UTC').add(days=-N, ...)".to_string()),
                 )),
-
                 // airflow.utils.helpers
                 ["airflow", "utils", "helpers", "chain"] => Some((
                     qualname.to_string(),
@@ -394,6 +488,10 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
                     qualname.to_string(),
                     Replacement::Name("airflow.www.auth.has_access_*".to_string()),
                 )),
+                ["airflow", "www", "auth", "has_access_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.www.auth.has_access_dataset.has_access_asset".to_string()),
+                )),
                 ["airflow", "www", "utils", "get_sensitive_variables_fields"] => Some((
                     qualname.to_string(),
                     Replacement::Name(
@@ -407,6 +505,82 @@ fn removed_name(checker: &mut Checker, expr: &Expr, ranged: impl Ranged) {
                         "airflow.utils.log.secrets_masker.should_hide_value_for_key".to_string(),
                     ),
                 )),
+                // airflow.providers.amazon
+                ["airflow", "providers", "amazon", "aws", "datasets", "s3", "create_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.amazon.aws.assets.s3.create_asset".to_string()),
+                )),
+                ["airflow", "providers", "amazon", "aws", "datasets", "s3", "convert_dataset_to_openlineage"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.amazon.aws.assets.s3.convert_asset_to_openlineage".to_string()),
+                )),
+                ["airflow", "providers", "amazon", "aws", "datasets", "s3", "sanitize_uri"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.amazon.aws.assets.s3.sanitize_uri".to_string()),
+                )),
+                ["airflow", "providers", "amazon", "auth_manager", "avp", "entities", "AvpEntities", "DATASET"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.amazon.auth_manager.avp.entities.AvpEntities.ASSET".to_string()),
+                )),
+                // airflow.providers.common.io
+                ["airflow", "providers", "common", "io", "datasets", "file", "create_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.common.io.assets.file.create_asset".to_string()),
+                )),
+                ["airflow", "providers", "common", "io", "datasets", "file", "convert_dataset_to_openlineage"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.common.io.assets.file.convert_asset_to_openlineage".to_string()),
+                )),
+                ["airflow", "providers", "common", "io", "datasets", "file", "sanitize_uri"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.common.io.assets.file.sanitize_uri".to_string()),
+                )),
+                // airflow.providers.fab
+                ["airflow", "providers", "fab", "auth_manager", "fab_auth_manager", "is_authorized_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.fab.auth_manager.fab_auth_manager.is_authorized_asset".to_string()),
+                )),
+                // airflow.providers.google
+                ["airflow", "providers", "google", "datasets", "bigquery", "create_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.google.assets.bigquery.create_asset".to_string()),
+                )),
+                ["airflow", "providers", "google", "datasets", "gcs", "create_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.google.assets.gcs.create_asset".to_string()),
+                )),
+                ["airflow", "providers", "google", "datasets", "gcs", "convert_dataset_to_openlineage"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.google.assets.gcs.convert_asset_to_openlineage".to_string()),
+                )),
+                ["airflow", "providers", "google", "datasets", "gcs", "sanitize_uri"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.google.assets.gcs.sanitize_uri".to_string()),
+                )),
+                // airflow.providers.mysql
+                ["airflow", "providers", "mysql", "datasets", "mysql", "sanitize_uri"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.mysql.assets.mysql.sanitize_uri".to_string()),
+                )),
+                // airflow.providers.postgres
+                ["airflow", "providers", "postgres", "datasets", "postgres", "sanitize_uri"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.postgres.assets.postgres.sanitize_uri".to_string()),
+                )),
+                // airflow.providers.openlineage
+                ["airflow", "providers", "openlineage", "utils", "utils", "DatasetInfo"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.openlineage.utils.utils.AssetInfo".to_string()),
+                )),
+                ["airflow", "providers", "openlineage", "utils", "utils", "translate_airflow_dataset"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.openlineage.utils.utils.translate_airflow_asset".to_string()),
+                )),
+                // airflow.providers.trino
+                ["airflow", "providers", "trino", "datasets", "trino", "sanitize_uri"] => Some((
+                    qualname.to_string(),
+                    Replacement::Name("airflow.providers.trino.assets.trino.sanitize_uri".to_string()),
+                )),
                 _ => None,
             });
     if let Some((deprecated, replacement)) = result {

crates/ruff_linter/src/rules/perflint/rules/manual_list_comprehension.rs

@@ -237,31 +237,12 @@ pub(crate) fn manual_list_comprehension(checker: &mut Checker, for_stmt: &ast::S
     // filtered = [x for x in y]
     // print(x)
     // ```
-    let last_target_binding = checker
+    let target_binding = checker
         .semantic()
-        .lookup_symbol(for_stmt_target_id)
-        .expect("for loop target must exist");
-
-    let target_binding = {
-        let mut bindings = [last_target_binding].into_iter().chain(
-            checker
-                .semantic()
-                .shadowed_bindings(checker.semantic().scope_id, last_target_binding)
-                .filter_map(|shadowed| shadowed.same_scope().then_some(shadowed.shadowed_id())),
-        );
-
-        bindings
-            .find_map(|binding_id| {
-                let binding = checker.semantic().binding(binding_id);
-                binding
-                    .statement(checker.semantic())
-                    .and_then(ast::Stmt::as_for_stmt)
-                    .is_some_and(|stmt| stmt.range == for_stmt.range)
-                    .then_some(binding)
-            })
-            .expect("for target binding must exist")
-    };
-
+        .bindings
+        .iter()
+        .find(|binding| for_stmt.target.range() == binding.range)
+        .unwrap();
     // If any references to the loop target variable are after the loop,
     // then converting it into a comprehension would cause a NameError
     if target_binding

crates/ruff_linter/src/rules/perflint/snapshots/ruff_linter__rules__perflint__tests__preview__PERF401_PERF401.py.snap

@@ -484,3 +484,5 @@ PERF401.py:245:13: PERF401 [*] Use `list.extend` to create a transformed list
 245     |-            result.append(a + 1)  # PERF401
     244 |+        result.extend(a + 1 for a in values)  # PERF401
 246 245 |     result = []
+247 246 | 
+248 247 | def f():

crates/ruff_linter/src/rules/pydocstyle/mod.rs

@@ -32,8 +32,8 @@ mod tests {
     #[test_case(Rule::EndsInPeriod, Path::new("D400_415.py"))]
     #[test_case(Rule::EndsInPunctuation, Path::new("D.py"))]
     #[test_case(Rule::EndsInPunctuation, Path::new("D400_415.py"))]
-    #[test_case(Rule::FirstLineCapitalized, Path::new("D.py"))]
-    #[test_case(Rule::FirstLineCapitalized, Path::new("D403.py"))]
+    #[test_case(Rule::FirstWordUncapitalized, Path::new("D.py"))]
+    #[test_case(Rule::FirstWordUncapitalized, Path::new("D403.py"))]
     #[test_case(Rule::FitsOnOneLine, Path::new("D.py"))]
     #[test_case(Rule::IndentWithSpaces, Path::new("D.py"))]
     #[test_case(Rule::UndocumentedMagicMethod, Path::new("D.py"))]

crates/ruff_linter/src/rules/pydocstyle/rules/capitalized.rs

@@ -10,8 +10,8 @@ use crate::docstrings::Docstring;
 /// Checks for docstrings that do not start with a capital letter.
 ///
 /// ## Why is this bad?
-/// The first character in a docstring should be capitalized for, grammatical
-/// correctness and consistency.
+/// The first non-whitespace character in a docstring should be
+/// capitalized for grammatical correctness and consistency.
 ///
 /// ## Example
 /// ```python
@@ -30,16 +30,16 @@ use crate::docstrings::Docstring;
 /// - [NumPy Style Guide](https://numpydoc.readthedocs.io/en/latest/format.html)
 /// - [Google Python Style Guide - Docstrings](https://google.github.io/styleguide/pyguide.html#38-comments-and-docstrings)
 #[derive(ViolationMetadata)]
-pub(crate) struct FirstLineCapitalized {
+pub(crate) struct FirstWordUncapitalized {
     first_word: String,
     capitalized_word: String,
 }
 
-impl AlwaysFixableViolation for FirstLineCapitalized {
+impl AlwaysFixableViolation for FirstWordUncapitalized {
     #[derive_message_formats]
     fn message(&self) -> String {
         format!(
-            "First word of the first line should be capitalized: `{}` -> `{}`",
+            "First word of the docstring should be capitalized: `{}` -> `{}`",
             self.first_word, self.capitalized_word
         )
     }
@@ -59,7 +59,8 @@ pub(crate) fn capitalized(checker: &mut Checker, docstring: &Docstring) {
     }
 
     let body = docstring.body();
-    let first_word = body.split_once(' ').map_or_else(
+    let trim_start_body = body.trim_start();
+    let first_word = trim_start_body.split_once(' ').map_or_else(
         || {
             // If the docstring is a single word, trim the punctuation marks because
             // it makes the ASCII test below fail.
@@ -91,8 +92,10 @@ pub(crate) fn capitalized(checker: &mut Checker, docstring: &Docstring) {
 
     let capitalized_word = uppercase_first_char.to_string() + first_word_chars.as_str();
 
+    let leading_whitespace_len = body.text_len() - trim_start_body.text_len();
+
     let mut diagnostic = Diagnostic::new(
-        FirstLineCapitalized {
+        FirstWordUncapitalized {
             first_word: first_word.to_string(),
             capitalized_word: capitalized_word.to_string(),
         },
@@ -101,7 +104,7 @@ pub(crate) fn capitalized(checker: &mut Checker, docstring: &Docstring) {
 
     diagnostic.set_fix(Fix::safe_edit(Edit::range_replacement(
         capitalized_word,
-        TextRange::at(body.start(), first_word.text_len()),
+        TextRange::at(body.start() + leading_whitespace_len, first_word.text_len()),
     )));
 
     checker.diagnostics.push(diagnostic);

crates/ruff_linter/src/rules/pydocstyle/snapshots/ruff_linter__rules__pydocstyle__tests__D403_D403.py.snap

@@ -1,8 +1,7 @@
 ---
 source: crates/ruff_linter/src/rules/pydocstyle/mod.rs
-snapshot_kind: text
 ---
-D403.py:2:5: D403 [*] First word of the first line should be capitalized: `this` -> `This`
+D403.py:2:5: D403 [*] First word of the docstring should be capitalized: `this` -> `This`
   |
 1 | def bad_function():
 2 |     """this docstring is not capitalized"""
@@ -20,7 +19,7 @@ D403.py:2:5: D403 [*] First word of the first line should be capitalized: `this`
 4 4 | def good_function():
 5 5 |     """This docstring is capitalized."""
 
-D403.py:30:5: D403 [*] First word of the first line should be capitalized: `singleword` -> `Singleword`
+D403.py:30:5: D403 [*] First word of the docstring should be capitalized: `singleword` -> `Singleword`
    |
 29 | def single_word():
 30 |     """singleword."""
@@ -40,11 +39,13 @@ D403.py:30:5: D403 [*] First word of the first line should be capitalized: `sing
 32 32 | def single_word_no_dot():
 33 33 |     """singleword"""
 
-D403.py:33:5: D403 [*] First word of the first line should be capitalized: `singleword` -> `Singleword`
+D403.py:33:5: D403 [*] First word of the docstring should be capitalized: `singleword` -> `Singleword`
    |
 32 | def single_word_no_dot():
 33 |     """singleword"""
    |     ^^^^^^^^^^^^^^^^ D403
+34 | 
+35 | def first_word_lots_of_whitespace():
    |
    = help: Capitalize `singleword` to `Singleword`
 
@@ -54,3 +55,32 @@ D403.py:33:5: D403 [*] First word of the first line should be capitalized: `sing
 32 32 | def single_word_no_dot():
 33    |-    """singleword"""
    33 |+    """Singleword"""
+34 34 | 
+35 35 | def first_word_lots_of_whitespace():
+36 36 |     """
+
+D403.py:36:5: D403 [*] First word of the docstring should be capitalized: `here` -> `Here`
+   |
+35 |   def first_word_lots_of_whitespace():
+36 |       """
+   |  _____^
+37 | | 
+38 | | 
+39 | | 
+40 | |     here is the start of my docstring!
+41 | | 
+42 | |     What do you think?    
+43 | |     """
+   | |_______^ D403
+   |
+   = help: Capitalize `here` to `Here`
+
+ℹ Safe fix
+37 37 | 
+38 38 | 
+39 39 | 
+40    |-    here is the start of my docstring!
+   40 |+    Here is the start of my docstring!
+41 41 | 
+42 42 |     What do you think?    
+43 43 |     """

crates/ruff_linter/src/rules/pylint/rules/non_augmented_assignment.rs

@@ -1,10 +1,10 @@
-use ast::{Expr, StmtAugAssign};
+use ast::Expr;
 use ruff_diagnostics::{AlwaysFixableViolation, Diagnostic, Edit, Fix};
 use ruff_macros::{derive_message_formats, ViolationMetadata};
 use ruff_python_ast as ast;
 use ruff_python_ast::comparable::ComparableExpr;
-use ruff_python_ast::Operator;
-use ruff_python_codegen::Generator;
+use ruff_python_ast::parenthesize::parenthesized_range;
+use ruff_python_ast::{AstNode, ExprBinOp, ExpressionRef, Operator};
 use ruff_text_size::{Ranged, TextRange};
 
 use crate::checkers::ast::Checker;
@@ -103,11 +103,12 @@ pub(crate) fn non_augmented_assignment(checker: &mut Checker, assign: &ast::Stmt
     if ComparableExpr::from(target) == ComparableExpr::from(&value.left) {
         let mut diagnostic = Diagnostic::new(NonAugmentedAssignment { operator }, assign.range());
         diagnostic.set_fix(Fix::unsafe_edit(augmented_assignment(
-            checker.generator(),
+            checker,
             target,
-            value.op,
+            operator,
             &value.right,
-            assign.range(),
+            value,
+            assign.range,
         )));
         checker.diagnostics.push(diagnostic);
         return;
@@ -121,11 +122,12 @@ pub(crate) fn non_augmented_assignment(checker: &mut Checker, assign: &ast::Stmt
     {
         let mut diagnostic = Diagnostic::new(NonAugmentedAssignment { operator }, assign.range());
         diagnostic.set_fix(Fix::unsafe_edit(augmented_assignment(
-            checker.generator(),
+            checker,
             target,
-            value.op,
+            operator,
             &value.left,
-            assign.range(),
+            value,
+            assign.range,
         )));
         checker.diagnostics.push(diagnostic);
     }
@@ -135,21 +137,30 @@ pub(crate) fn non_augmented_assignment(checker: &mut Checker, assign: &ast::Stmt
 ///
 /// For example, given `x = x + 1`, the fix would be `x += 1`.
 fn augmented_assignment(
-    generator: Generator,
+    checker: &Checker,
     target: &Expr,
-    operator: Operator,
+    operator: AugmentedOperator,
     right_operand: &Expr,
+    original_expr: &ExprBinOp,
     range: TextRange,
 ) -> Edit {
-    Edit::range_replacement(
-        generator.stmt(&ast::Stmt::AugAssign(StmtAugAssign {
-            range: TextRange::default(),
-            target: Box::new(target.clone()),
-            op: operator,
-            value: Box::new(right_operand.clone()),
-        })),
-        range,
-    )
+    let locator = checker.locator();
+
+    let right_operand_ref = ExpressionRef::from(right_operand);
+    let parent = original_expr.as_any_node_ref();
+    let comment_ranges = checker.comment_ranges();
+    let source = checker.source();
+
+    let right_operand_range =
+        parenthesized_range(right_operand_ref, parent, comment_ranges, source)
+            .unwrap_or(right_operand.range());
+    let right_operand_expr = locator.slice(right_operand_range);
+
+    let target_expr = locator.slice(target);
+
+    let new_content = format!("{target_expr} {operator} {right_operand_expr}");
+
+    Edit::range_replacement(new_content, range)
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]

crates/ruff_linter/src/rules/pylint/snapshots/ruff_linter__rules__pylint__tests__PLR6104_non_augmented_assignment.py.snap

@@ -269,7 +269,7 @@ non_augmented_assignment.py:29:1: PLR6104 [*] Use `&=` to perform an augmented a
 27 27 | to_cube = to_cube**to_cube
 28 28 | timeDiffSeconds = timeDiffSeconds % 60
 29    |-flags = flags & 0x1
-   29 |+flags &= 1
+   29 |+flags &= 0x1
 30 30 | flags = flags | 0x1
 31 31 | flags = flags ^ 0x1
 32 32 | flags = flags << 1
@@ -290,7 +290,7 @@ non_augmented_assignment.py:30:1: PLR6104 [*] Use `|=` to perform an augmented a
 28 28 | timeDiffSeconds = timeDiffSeconds % 60
 29 29 | flags = flags & 0x1
 30    |-flags = flags | 0x1
-   30 |+flags |= 1
+   30 |+flags |= 0x1
 31 31 | flags = flags ^ 0x1
 32 32 | flags = flags << 1
 33 33 | flags = flags >> 1
@@ -311,7 +311,7 @@ non_augmented_assignment.py:31:1: PLR6104 [*] Use `^=` to perform an augmented a
 29 29 | flags = flags & 0x1
 30 30 | flags = flags | 0x1
 31    |-flags = flags ^ 0x1
-   31 |+flags ^= 1
+   31 |+flags ^= 0x1
 32 32 | flags = flags << 1
 33 33 | flags = flags >> 1
 34 34 | mat1 = mat1 @ mat2
@@ -495,7 +495,7 @@ non_augmented_assignment.py:42:1: PLR6104 [*] Use `*=` to perform an augmented a
 40 40 | a_list[:] = a_list[:] * 3
 41 41 | 
 42    |-index = index * (index + 10)
-   42 |+index *= index + 10
+   42 |+index *= (index + 10)
 43 43 | 
 44 44 | 
 45 45 | class T:
@@ -524,8 +524,6 @@ non_augmented_assignment.py:51:1: PLR6104 [*] Use `+=` to perform an augmented a
 50 | obj = T()
 51 | obj.a = obj.a + 1
    | ^^^^^^^^^^^^^^^^^ PLR6104
-52 | 
-53 | # OK
    |
    = help: Replace with augmented assignment
 
@@ -536,5 +534,213 @@ non_augmented_assignment.py:51:1: PLR6104 [*] Use `+=` to perform an augmented a
 51    |-obj.a = obj.a + 1
    51 |+obj.a += 1
 52 52 | 
-53 53 | # OK
-54 54 | a_list[0] = a_list[:] * 3
+53 53 | 
+54 54 | a = a+-1
+
+non_augmented_assignment.py:54:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+54 | a = a+-1
+   | ^^^^^^^^ PLR6104
+55 | 
+56 | # Regression tests for https://github.com/astral-sh/ruff/issues/11672
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+51 51 | obj.a = obj.a + 1
+52 52 | 
+53 53 | 
+54    |-a = a+-1
+   54 |+a += -1
+55 55 | 
+56 56 | # Regression tests for https://github.com/astral-sh/ruff/issues/11672
+57 57 | test = 0x5
+
+non_augmented_assignment.py:58:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+56 | # Regression tests for https://github.com/astral-sh/ruff/issues/11672
+57 | test = 0x5
+58 | test = test + 0xBA
+   | ^^^^^^^^^^^^^^^^^^ PLR6104
+59 | 
+60 | test2 = b""
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+55 55 | 
+56 56 | # Regression tests for https://github.com/astral-sh/ruff/issues/11672
+57 57 | test = 0x5
+58    |-test = test + 0xBA
+   58 |+test += 0xBA
+59 59 | 
+60 60 | test2 = b""
+61 61 | test2 = test2 + b"\000"
+
+non_augmented_assignment.py:61:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+60 | test2 = b""
+61 | test2 = test2 + b"\000"
+   | ^^^^^^^^^^^^^^^^^^^^^^^ PLR6104
+62 | 
+63 | test3 = ""
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+58 58 | test = test + 0xBA
+59 59 | 
+60 60 | test2 = b""
+61    |-test2 = test2 + b"\000"
+   61 |+test2 += b"\000"
+62 62 | 
+63 63 | test3 = ""
+64 64 | test3 = test3 + (   a := R""
+
+non_augmented_assignment.py:64:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+63 |   test3 = ""
+64 | / test3 = test3 + (   a := R""
+65 | |                          f"oo"   )
+   | |__________________________________^ PLR6104
+66 |   
+67 |   test4 = []
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+61 61 | test2 = test2 + b"\000"
+62 62 | 
+63 63 | test3 = ""
+64    |-test3 = test3 + (   a := R""
+   64 |+test3 += (   a := R""
+65 65 |                          f"oo"   )
+66 66 | 
+67 67 | test4 = []
+
+non_augmented_assignment.py:68:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+67 |   test4 = []
+68 | / test4 = test4 + ( e
+69 | |                   for e in
+70 | |                   range(10)
+71 | |                   )
+   | |___________________^ PLR6104
+72 |   
+73 |   test5 = test5 + (
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+65 65 |                          f"oo"   )
+66 66 | 
+67 67 | test4 = []
+68    |-test4 = test4 + ( e
+   68 |+test4 += ( e
+69 69 |                   for e in
+70 70 |                   range(10)
+71 71 |                   )
+
+non_augmented_assignment.py:73:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+71 |                     )
+72 |   
+73 | / test5 = test5 + (
+74 | |     4
+75 | |     *
+76 | |     10
+77 | | )
+   | |_^ PLR6104
+78 |   
+79 |   test6 = test6 + \
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+70 70 |                   range(10)
+71 71 |                   )
+72 72 | 
+73    |-test5 = test5 + (
+   73 |+test5 += (
+74 74 |     4
+75 75 |     *
+76 76 |     10
+
+non_augmented_assignment.py:79:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+77 |   )
+78 |   
+79 | / test6 = test6 + \
+80 | |         (
+81 | |             4
+82 | |             *
+83 | |             10
+84 | |         )
+   | |_________^ PLR6104
+85 |   
+86 |   test7 = \
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+76 76 |     10
+77 77 | )
+78 78 | 
+79    |-test6 = test6 + \
+80    |-        (
+   79 |+test6 += (
+81 80 |             4
+82 81 |             *
+83 82 |             10
+
+non_augmented_assignment.py:86:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+84 |           )
+85 |   
+86 | / test7 = \
+87 | |         100 \
+88 | |     + test7
+   | |___________^ PLR6104
+89 |   
+90 |   test8 = \
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+83 83 |             10
+84 84 |         )
+85 85 | 
+86    |-test7 = \
+87    |-        100 \
+88    |-    + test7
+   86 |+test7 += 100
+89 87 | 
+90 88 | test8 = \
+91 89 |     886 \
+
+non_augmented_assignment.py:90:1: PLR6104 [*] Use `+=` to perform an augmented assignment directly
+   |
+88 |       + test7
+89 |   
+90 | / test8 = \
+91 | |     886 \
+92 | |     + \
+93 | |  \
+94 | |     test8
+   | |_________^ PLR6104
+   |
+   = help: Replace with augmented assignment
+
+ℹ Unsafe fix
+87 87 |         100 \
+88 88 |     + test7
+89 89 | 
+90    |-test8 = \
+91    |-    886 \
+92    |-    + \
+93    |- \
+94    |-    test8
+   90 |+test8 += 886
+95 91 | 
+96 92 | 
+97 93 | # OK

crates/ruff_python_trivia/src/tokenizer.rs

@@ -249,13 +249,13 @@ pub enum SimpleTokenKind {
     /// `;`
     Semi,
 
-    /// '/'
+    /// `/`
     Slash,
 
-    /// '*'
+    /// `*`
     Star,
 
-    /// `.`.
+    /// `.`
     Dot,
 
     /// `+`

crates/ruff_server/src/session/capabilities.rs

@@ -37,18 +37,12 @@ impl ResolvedClientCapabilities {
             .and_then(|workspace_edit| workspace_edit.document_changes)
             .unwrap_or_default();
 
-        let workspace_refresh = true;
-
-        // TODO(jane): Once the bug involving workspace.diagnostic(s) deserialization has been fixed,
-        // uncomment this.
-        /*
         let workspace_refresh = client_capabilities
             .workspace
             .as_ref()
-            .and_then(|workspace| workspace.diagnostic.as_ref())
+            .and_then(|workspace| workspace.diagnostics.as_ref())
             .and_then(|diagnostic| diagnostic.refresh_support)
             .unwrap_or_default();
-        */
 
         let pull_diagnostics = client_capabilities
             .text_document

docs/editors/features.md

@@ -95,6 +95,7 @@ Similar to Ruff's CLI, the Ruff Language Server fully supports Jupyter Notebook
 capabilities available to Python files.
 
 !!! note
+
     Unlike [`ruff-lsp`](https://github.com/astral-sh/ruff-lsp) and similar to the Ruff's CLI, the
     native language server requires user to explicitly include the Jupyter Notebook files in the set
     of files to lint and format. Refer to the [Jupyter Notebook discovery](https://docs.astral.sh/ruff/configuration/#jupyter-notebook-discovery)

docs/editors/index.md

@@ -22,6 +22,7 @@ The Ruff Language Server was available first in Ruff [v0.4.5](https://astral.sh/
 in beta and stabilized in Ruff [v0.5.3](https://github.com/astral-sh/ruff/releases/tag/0.5.3).
 
 !!! note
+
     This is the documentation for Ruff's built-in language server written in Rust (`ruff server`).
     If you are looking for the documentation for the `ruff-lsp` language server, please refer to the
     [README](https://github.com/astral-sh/ruff-lsp) of the `ruff-lsp` repository.

docs/editors/migration.md

@@ -4,6 +4,7 @@ While `ruff server` supports the same feature set as [`ruff-lsp`](https://github
 `ruff server` may require changes to your Ruff or language server configuration.
 
 !!! note
+
     The [VS Code extension](https://github.com/astral-sh/ruff-vscode) settings include documentation to indicate which
     settings are supported by `ruff server`. As such, this migration guide is primarily targeted at editors that lack
     explicit documentation for `ruff server` settings, such as Helix or Neovim.
@@ -20,6 +21,7 @@ Several `ruff-lsp` settings are not supported by `ruff server`. These are, as fo
 - `path`
 
 !!! note
+
     Some of these settings, like `interpreter` and `path`, are still accepted by the VS Code
     extension. `path`, in particular, can be used to specify a dedicated binary to use when
     initializing `ruff server`. But the language server itself will no longer accept such settings.

docs/editors/settings.md

@@ -23,6 +23,7 @@ behavior of the Ruff CLI.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.configuration": "~/path/to/ruff.toml"
@@ -30,6 +31,7 @@ behavior of the Ruff CLI.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -41,6 +43,7 @@ behavior of the Ruff CLI.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -72,6 +75,7 @@ configuration is prioritized over `ruff.toml` and `pyproject.toml` files.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.configurationPreference": "filesystemFirst"
@@ -79,6 +83,7 @@ configuration is prioritized over `ruff.toml` and `pyproject.toml` files.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -90,6 +95,7 @@ configuration is prioritized over `ruff.toml` and `pyproject.toml` files.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -116,6 +122,7 @@ documentation](https://docs.astral.sh/ruff/settings/#exclude) for more details.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.exclude": ["**/tests/**"]
@@ -123,6 +130,7 @@ documentation](https://docs.astral.sh/ruff/settings/#exclude) for more details.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -134,6 +142,7 @@ documentation](https://docs.astral.sh/ruff/settings/#exclude) for more details.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -159,6 +168,7 @@ The line length to use for the linter and formatter.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lineLength": 100
@@ -166,6 +176,7 @@ The line length to use for the linter and formatter.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -177,6 +188,7 @@ The line length to use for the linter and formatter.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -202,6 +214,7 @@ Whether to register the server as capable of handling `source.fixAll` code actio
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.fixAll": false
@@ -209,6 +222,7 @@ Whether to register the server as capable of handling `source.fixAll` code actio
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -220,6 +234,7 @@ Whether to register the server as capable of handling `source.fixAll` code actio
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -245,6 +260,7 @@ Whether to register the server as capable of handling `source.organizeImports` c
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.organizeImports": false
@@ -252,6 +268,7 @@ Whether to register the server as capable of handling `source.organizeImports` c
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -263,6 +280,7 @@ Whether to register the server as capable of handling `source.organizeImports` c
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -290,6 +308,7 @@ Whether to show syntax error diagnostics.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.showSyntaxErrors": false
@@ -297,6 +316,7 @@ Whether to show syntax error diagnostics.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -308,6 +328,7 @@ Whether to show syntax error diagnostics.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -333,6 +354,7 @@ The log level to use for the server.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.logLevel": "debug"
@@ -340,6 +362,7 @@ The log level to use for the server.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -351,6 +374,7 @@ The log level to use for the server.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -378,6 +402,7 @@ If not set, logs will be written to stderr.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.logFile": "~/path/to/ruff.log"
@@ -385,6 +410,7 @@ If not set, logs will be written to stderr.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -396,6 +422,7 @@ If not set, logs will be written to stderr.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -425,6 +452,7 @@ Whether to display Quick Fix actions to disable rules via `noqa` suppression com
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.codeAction.disableRuleComment.enable": false
@@ -432,6 +460,7 @@ Whether to display Quick Fix actions to disable rules via `noqa` suppression com
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -447,6 +476,7 @@ Whether to display Quick Fix actions to disable rules via `noqa` suppression com
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -476,6 +506,7 @@ Whether to display Quick Fix actions to autofix violations.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.codeAction.fixViolation.enable": false
@@ -483,6 +514,7 @@ Whether to display Quick Fix actions to autofix violations.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -498,6 +530,7 @@ Whether to display Quick Fix actions to autofix violations.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -531,6 +564,7 @@ Whether to enable linting. Set to `false` to use Ruff exclusively as a formatter
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lint.enable": false
@@ -538,6 +572,7 @@ Whether to enable linting. Set to `false` to use Ruff exclusively as a formatter
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -551,6 +586,7 @@ Whether to enable linting. Set to `false` to use Ruff exclusively as a formatter
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -580,6 +616,7 @@ Whether to enable Ruff's preview mode when linting.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lint.preview": true
@@ -587,6 +624,7 @@ Whether to enable Ruff's preview mode when linting.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -600,6 +638,7 @@ Whether to enable Ruff's preview mode when linting.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -627,6 +666,7 @@ Rules to enable by default. See [the documentation](https://docs.astral.sh/ruff/
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lint.select": ["E", "F"]
@@ -634,6 +674,7 @@ Rules to enable by default. See [the documentation](https://docs.astral.sh/ruff/
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -647,6 +688,7 @@ Rules to enable by default. See [the documentation](https://docs.astral.sh/ruff/
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -674,6 +716,7 @@ Rules to enable in addition to those in [`lint.select`](#select).
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lint.extendSelect": ["W"]
@@ -681,6 +724,7 @@ Rules to enable in addition to those in [`lint.select`](#select).
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -694,6 +738,7 @@ Rules to enable in addition to those in [`lint.select`](#select).
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -721,6 +766,7 @@ Rules to disable by default. See [the documentation](https://docs.astral.sh/ruff
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lint.ignore": ["E4", "E7"]
@@ -728,6 +774,7 @@ Rules to disable by default. See [the documentation](https://docs.astral.sh/ruff
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -741,6 +788,7 @@ Rules to disable by default. See [the documentation](https://docs.astral.sh/ruff
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -768,6 +816,7 @@ Rules to disable in addition to those in [`lint.ignore`](#ignore).
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.lint.extendIgnore": ["W1"]
@@ -775,6 +824,7 @@ Rules to disable in addition to those in [`lint.ignore`](#ignore).
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -788,6 +838,7 @@ Rules to disable in addition to those in [`lint.ignore`](#ignore).
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {
@@ -819,6 +870,7 @@ Whether to enable Ruff's preview mode when formatting.
 **Example usage**:
 
 === "VS Code"
+
     ```json
     {
         "ruff.format.preview": true
@@ -826,6 +878,7 @@ Whether to enable Ruff's preview mode when formatting.
     ```
 
 === "Neovim"
+
     ```lua
     require('lspconfig').ruff.setup {
       init_options = {
@@ -839,6 +892,7 @@ Whether to enable Ruff's preview mode when formatting.
     ```
 
 === "Zed"
+
     ```json
     {
       "lsp": {

docs/editors/setup.md

@@ -8,11 +8,13 @@ regardless of editor, there are several settings which have changed or are no lo
 the [migration guide](./migration.md) for more.
 
 !!! note
+
     The setup instructions provided below are on a best-effort basis. If you encounter any issues
     while setting up the Ruff in an editor, please [open an issue](https://github.com/astral-sh/ruff/issues/new)
     for assistance and help in improving this documentation.
 
 !!! tip
+
     Regardless of the editor, it is recommended to disable the older language server
     ([`ruff-lsp`](https://github.com/astral-sh/ruff-lsp)) to prevent any conflicts.
 
@@ -45,6 +47,7 @@ require('lspconfig').ruff.setup({
 ```
 
 !!! note
+
     If the installed version of `nvim-lspconfig` includes the changes from
     [neovim/nvim-lspconfig@`70d1c2c`](https://github.com/neovim/nvim-lspconfig/commit/70d1c2c31a88af4b36019dc1551be16bffb8f9db),
     you will need to use Ruff version `0.5.3` or later.
@@ -242,6 +245,7 @@ language-servers = ["ruff", "pylsp"]
 ```
 
 !!! note
+
     Support for multiple language servers for a language is only available in Helix version
     [`23.10`](https://github.com/helix-editor/helix/blob/master/CHANGELOG.md#2310-2023-10-24) and later.
 
@@ -287,6 +291,7 @@ logLevel = "debug"
 You can also divert Ruff's logs to a separate file with the [`logFile`](./settings.md#logfile) setting.
 
 !!! note
+
     Setting `RUFF_TRACE=verbose` does not enable Helix's verbose mode by itself. You'll need to run
     Helix with `-v` for verbose logging.
 
@@ -313,6 +318,7 @@ See [LSP Client documentation](https://docs.kde.org/stable5/en/kate/kate/kate-ap
 on how to configure the server from there.
 
 !!! important
+
     Kate's LSP Client plugin does not support multiple servers for the same language. As a
     workaround, you can use the [`python-lsp-server`](https://github.com/python-lsp/python-lsp-server)
     along with the [`python-lsp-ruff`](https://github.com/python-lsp/python-lsp-ruff) plugin to
@@ -431,6 +437,7 @@ under the [`lsp.ruff.initialization_options.settings`](https://zed.dev/docs/conf
 ```
 
 !!! note
+
     Support for multiple formatters for a given language is only available in Zed version
     `0.146.0` and later.
 
@@ -438,6 +445,7 @@ You can configure Ruff to format Python code on-save by registering the Ruff for
 and enabling the [`format_on_save`](https://zed.dev/docs/configuring-zed#format-on-save) setting:
 
 === "Zed 0.146.0+"
+
     ```json
     {
       "languages": {
@@ -460,6 +468,7 @@ You can configure Ruff to fix lint violations and/or organize imports on-save by
 `source.fixAll.ruff` and `source.organizeImports.ruff` code actions respectively:
 
 === "Zed 0.146.0+"
+
     ```json
     {
       "languages": {
@@ -485,12 +494,14 @@ Taken together, you can configure Ruff to format, fix, and organize imports on-s
 following `settings.json`:
 
 !!! note
+
     For this configuration, it is important to use the correct order of the code action and
     formatter language server settings. The code actions should be defined before the formatter to
     ensure that the formatter takes care of any remaining style issues after the code actions have
     been applied.
 
 === "Zed 0.146.0+"
+
     ```json
     {
       "languages": {

docs/requirements-insiders.txt

@@ -1,11 +1,10 @@
 PyYAML==6.0.2
-ruff==0.8.2
+ruff==0.8.3
 mkdocs==1.6.1
 mkdocs-material @ git+ssh://git@github.com/astral-sh/mkdocs-material-insiders.git@39da7a5e761410349e9a1b8abf593b0cdd5453ff
 mkdocs-redirects==1.2.2
 mdformat==0.7.19
-mdformat-mkdocs==3.1.1
-mdformat-admon==2.0.6
+mdformat-mkdocs==4.0.0
 # Using a commit from pygments main branch so we get
 # https://github.com/pygments/pygments/pull/2773 before it's been released
 pygments @ git+https://github.com/pygments/pygments.git@67b460fdde6d9a00342b5102b37b3a8399f0e8ef

docs/requirements.txt

@@ -1,11 +1,10 @@
 PyYAML==6.0.2
-ruff==0.8.2
+ruff==0.8.3
 mkdocs==1.6.1
 mkdocs-material==9.5.38
 mkdocs-redirects==1.2.2
 mdformat==0.7.19
-mdformat-mkdocs==3.1.1
-mdformat-admon==2.0.6
+mdformat-mkdocs==4.0.0
 # Using a commit from pygments main branch so we get
 # https://github.com/pygments/pygments/pull/2773 before it's been released
 pygments @ git+https://github.com/pygments/pygments.git@67b460fdde6d9a00342b5102b37b3a8399f0e8ef

fuzz/Cargo.toml

@@ -2,8 +2,8 @@
 name = "ruff-fuzz"
 version = "0.0.0"
 authors = [
-  "Charlie Marsh <charlie.r.marsh@gmail.com>",
-  "Addison Crump <research@addisoncrump.info>",
+    "Charlie Marsh <charlie.r.marsh@gmail.com>",
+    "Addison Crump <research@addisoncrump.info>",
 ]
 publish = false
 edition = "2021"
@@ -25,11 +25,11 @@ ruff_python_ast = { path = "../crates/ruff_python_ast" }
 ruff_python_codegen = { path = "../crates/ruff_python_codegen" }
 ruff_python_parser = { path = "../crates/ruff_python_parser" }
 ruff_source_file = { path = "../crates/ruff_source_file" }
-ruff_python_formatter = { path = "../crates/ruff_python_formatter"}
+ruff_python_formatter = { path = "../crates/ruff_python_formatter" }
 ruff_text_size = { path = "../crates/ruff_text_size" }
 
 libfuzzer-sys = { git = "https://github.com/rust-fuzz/libfuzzer", default-features = false }
-salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "254c749b02cde2fd29852a7463a33e800b771758" }
+salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "3c7f1694c9efba751dbeeacfbc93b227586e316a" }
 similar = { version = "2.5.0" }
 tracing = { version = "0.1.40" }
 

fuzz/fuzz_targets/red_knot_check_invalid_syntax.rs

@@ -22,12 +22,13 @@ use ruff_python_parser::{parse_unchecked, Mode};
 ///
 /// Uses an in memory filesystem and it stubs out the vendored files by default.
 #[salsa::db]
+#[derive(Clone)]
 struct TestDb {
     storage: salsa::Storage<Self>,
     files: Files,
     system: TestSystem,
     vendored: VendoredFileSystem,
-    events: std::sync::Arc<std::sync::Mutex<Vec<salsa::Event>>>,
+    events: std::sync::Arc<Mutex<Vec<salsa::Event>>>,
     rule_selection: std::sync::Arc<RuleSelection>,
 }
 

playground/api/package-lock.json

@@ -16,7 +16,7 @@
         "@cloudflare/workers-types": "^4.20230801.0",
         "miniflare": "^3.20230801.1",
         "typescript": "^5.1.6",
-        "wrangler": "3.93.0"
+        "wrangler": "3.95.0"
       }
     },
     "node_modules/@cloudflare/kv-asset-handler": {
@@ -118,9 +118,9 @@
       }
     },
     "node_modules/@cloudflare/workers-shared": {
-      "version": "0.10.0",
-      "resolved": "https://registry.npmjs.org/@cloudflare/workers-shared/-/workers-shared-0.10.0.tgz",
-      "integrity": "sha512-j3EwZBc9ctavmFVOQT1gqztRO/Plx4ZR0LMEEOif+5YoCcuD1P7/NEjlODPMc5a1w+8+7A/H+Ci8Ihd55+x0Zw==",
+      "version": "0.11.0",
+      "resolved": "https://registry.npmjs.org/@cloudflare/workers-shared/-/workers-shared-0.11.0.tgz",
+      "integrity": "sha512-A+lQ8xp7992qSeMmuQ0ssL6CPmm+ZmAv6Ddikan0n1jjpMAic+97l7xtVIsswSn9iLMFPYQ9uNN/8Fl0AgARIQ==",
       "dev": true,
       "license": "MIT OR Apache-2.0",
       "dependencies": {
@@ -1453,14 +1453,14 @@
       }
     },
     "node_modules/wrangler": {
-      "version": "3.93.0",
-      "resolved": "https://registry.npmjs.org/wrangler/-/wrangler-3.93.0.tgz",
-      "integrity": "sha512-+wfxjOrtm6YgDS+NdJkB6aiBIS3ED97mNRQmfrEShRJW4pVo4sWY6oQ1FsGT+j4tGHplrTbWCE6U5yTgjNW/lw==",
+      "version": "3.95.0",
+      "resolved": "https://registry.npmjs.org/wrangler/-/wrangler-3.95.0.tgz",
+      "integrity": "sha512-3w5852i3FNyDz421K2Qk4v5L8jjwegO5O8E1+VAQmjnm82HFNxpIRUBq0bmM7CTLvOPI/Jjcmj/eAWjQBL7QYg==",
       "dev": true,
       "license": "MIT OR Apache-2.0",
       "dependencies": {
         "@cloudflare/kv-asset-handler": "0.3.4",
-        "@cloudflare/workers-shared": "0.10.0",
+        "@cloudflare/workers-shared": "0.11.0",
         "@esbuild-plugins/node-globals-polyfill": "^0.2.3",
         "@esbuild-plugins/node-modules-polyfill": "^0.2.2",
         "blake3-wasm": "^2.1.5",

playground/api/package.json

@@ -5,7 +5,7 @@
     "@cloudflare/workers-types": "^4.20230801.0",
     "miniflare": "^3.20230801.1",
     "typescript": "^5.1.6",
-    "wrangler": "3.93.0"
+    "wrangler": "3.95.0"
   },
   "private": true,
   "scripts": {

playground/package-lock.json

@@ -1219,25 +1219,27 @@
       }
     },
     "node_modules/@types/react-dom": {
-      "version": "19.0.1",
-      "resolved": "https://registry.npmjs.org/@types/react-dom/-/react-dom-19.0.1.tgz",
-      "integrity": "sha512-hljHij7MpWPKF6u5vojuyfV0YA4YURsQG7KT6SzV0Zs2BXAtgdTxG6A229Ub/xiWV4w/7JL8fi6aAyjshH4meA==",
+      "version": "19.0.2",
+      "resolved": "https://registry.npmjs.org/@types/react-dom/-/react-dom-19.0.2.tgz",
+      "integrity": "sha512-c1s+7TKFaDRRxr1TxccIX2u7sfCnc3RxkVyBIUA2lCpyqCF+QoAwQ/CBg7bsMdVwP120HEH143VQezKtef5nCg==",
       "dev": true,
-      "dependencies": {
-        "@types/react": "*"
+      "license": "MIT",
+      "peerDependencies": {
+        "@types/react": "^19.0.0"
       }
     },
     "node_modules/@typescript-eslint/eslint-plugin": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.17.0.tgz",
-      "integrity": "sha512-HU1KAdW3Tt8zQkdvNoIijfWDMvdSweFYm4hWh+KwhPstv+sCmWb89hCIP8msFm9N1R/ooh9honpSuvqKWlYy3w==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/eslint-plugin/-/eslint-plugin-8.18.0.tgz",
+      "integrity": "sha512-NR2yS7qUqCL7AIxdJUQf2MKKNDVNaig/dEB0GBLU7D+ZdHgK1NoH/3wsgO3OnPVipn51tG3MAwaODEGil70WEw==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
         "@eslint-community/regexpp": "^4.10.0",
-        "@typescript-eslint/scope-manager": "8.17.0",
-        "@typescript-eslint/type-utils": "8.17.0",
-        "@typescript-eslint/utils": "8.17.0",
-        "@typescript-eslint/visitor-keys": "8.17.0",
+        "@typescript-eslint/scope-manager": "8.18.0",
+        "@typescript-eslint/type-utils": "8.18.0",
+        "@typescript-eslint/utils": "8.18.0",
+        "@typescript-eslint/visitor-keys": "8.18.0",
         "graphemer": "^1.4.0",
         "ignore": "^5.3.1",
         "natural-compare": "^1.4.0",
@@ -1252,24 +1254,21 @@
       },
       "peerDependencies": {
         "@typescript-eslint/parser": "^8.0.0 || ^8.0.0-alpha.0",
-        "eslint": "^8.57.0 || ^9.0.0"
-      },
-      "peerDependenciesMeta": {
-        "typescript": {
-          "optional": true
-        }
+        "eslint": "^8.57.0 || ^9.0.0",
+        "typescript": ">=4.8.4 <5.8.0"
       }
     },
     "node_modules/@typescript-eslint/parser": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-8.17.0.tgz",
-      "integrity": "sha512-Drp39TXuUlD49F7ilHHCG7TTg8IkA+hxCuULdmzWYICxGXvDXmDmWEjJYZQYgf6l/TFfYNE167m7isnc3xlIEg==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/parser/-/parser-8.18.0.tgz",
+      "integrity": "sha512-hgUZ3kTEpVzKaK3uNibExUYm6SKKOmTU2BOxBSvOYwtJEPdVQ70kZJpPjstlnhCHcuc2WGfSbpKlb/69ttyN5Q==",
       "dev": true,
+      "license": "MITClause",
       "dependencies": {
-        "@typescript-eslint/scope-manager": "8.17.0",
-        "@typescript-eslint/types": "8.17.0",
-        "@typescript-eslint/typescript-estree": "8.17.0",
-        "@typescript-eslint/visitor-keys": "8.17.0",
+        "@typescript-eslint/scope-manager": "8.18.0",
+        "@typescript-eslint/types": "8.18.0",
+        "@typescript-eslint/typescript-estree": "8.18.0",
+        "@typescript-eslint/visitor-keys": "8.18.0",
         "debug": "^4.3.4"
       },
       "engines": {
@@ -1280,22 +1279,19 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "eslint": "^8.57.0 || ^9.0.0"
-      },
-      "peerDependenciesMeta": {
-        "typescript": {
-          "optional": true
-        }
+        "eslint": "^8.57.0 || ^9.0.0",
+        "typescript": ">=4.8.4 <5.8.0"
       }
     },
     "node_modules/@typescript-eslint/scope-manager": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/scope-manager/-/scope-manager-8.17.0.tgz",
-      "integrity": "sha512-/ewp4XjvnxaREtqsZjF4Mfn078RD/9GmiEAtTeLQ7yFdKnqwTOgRMSvFz4et9U5RiJQ15WTGXPLj89zGusvxBg==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/scope-manager/-/scope-manager-8.18.0.tgz",
+      "integrity": "sha512-PNGcHop0jkK2WVYGotk/hxj+UFLhXtGPiGtiaWgVBVP1jhMoMCHlTyJA+hEj4rszoSdLTK3fN4oOatrL0Cp+Xw==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/types": "8.17.0",
-        "@typescript-eslint/visitor-keys": "8.17.0"
+        "@typescript-eslint/types": "8.18.0",
+        "@typescript-eslint/visitor-keys": "8.18.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1306,13 +1302,14 @@
       }
     },
     "node_modules/@typescript-eslint/type-utils": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/type-utils/-/type-utils-8.17.0.tgz",
-      "integrity": "sha512-q38llWJYPd63rRnJ6wY/ZQqIzPrBCkPdpIsaCfkR3Q4t3p6sb422zougfad4TFW9+ElIFLVDzWGiGAfbb/v2qw==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/type-utils/-/type-utils-8.18.0.tgz",
+      "integrity": "sha512-er224jRepVAVLnMF2Q7MZJCq5CsdH2oqjP4dT7K6ij09Kyd+R21r7UVJrF0buMVdZS5QRhDzpvzAxHxabQadow==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/typescript-estree": "8.17.0",
-        "@typescript-eslint/utils": "8.17.0",
+        "@typescript-eslint/typescript-estree": "8.18.0",
+        "@typescript-eslint/utils": "8.18.0",
         "debug": "^4.3.4",
         "ts-api-utils": "^1.3.0"
       },
@@ -1324,19 +1321,16 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "eslint": "^8.57.0 || ^9.0.0"
-      },
-      "peerDependenciesMeta": {
-        "typescript": {
-          "optional": true
-        }
+        "eslint": "^8.57.0 || ^9.0.0",
+        "typescript": ">=4.8.4 <5.8.0"
       }
     },
     "node_modules/@typescript-eslint/types": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/types/-/types-8.17.0.tgz",
-      "integrity": "sha512-gY2TVzeve3z6crqh2Ic7Cr+CAv6pfb0Egee7J5UAVWCpVvDI/F71wNfolIim4FE6hT15EbpZFVUj9j5i38jYXA==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/types/-/types-8.18.0.tgz",
+      "integrity": "sha512-FNYxgyTCAnFwTrzpBGq+zrnoTO4x0c1CKYY5MuUTzpScqmY5fmsh2o3+57lqdI3NZucBDCzDgdEbIaNfAjAHQA==",
       "dev": true,
+      "license": "MIT",
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
       },
@@ -1346,13 +1340,14 @@
       }
     },
     "node_modules/@typescript-eslint/typescript-estree": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-8.17.0.tgz",
-      "integrity": "sha512-JqkOopc1nRKZpX+opvKqnM3XUlM7LpFMD0lYxTqOTKQfCWAmxw45e3qlOCsEqEB2yuacujivudOFpCnqkBDNMw==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/typescript-estree/-/typescript-estree-8.18.0.tgz",
+      "integrity": "sha512-rqQgFRu6yPkauz+ms3nQpohwejS8bvgbPyIDq13cgEDbkXt4LH4OkDMT0/fN1RUtzG8e8AKJyDBoocuQh8qNeg==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/types": "8.17.0",
-        "@typescript-eslint/visitor-keys": "8.17.0",
+        "@typescript-eslint/types": "8.18.0",
+        "@typescript-eslint/visitor-keys": "8.18.0",
         "debug": "^4.3.4",
         "fast-glob": "^3.3.2",
         "is-glob": "^4.0.3",
@@ -1367,22 +1362,21 @@
         "type": "opencollective",
         "url": "https://opencollective.com/typescript-eslint"
       },
-      "peerDependenciesMeta": {
-        "typescript": {
-          "optional": true
-        }
+      "peerDependencies": {
+        "typescript": ">=4.8.4 <5.8.0"
       }
     },
     "node_modules/@typescript-eslint/utils": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/utils/-/utils-8.17.0.tgz",
-      "integrity": "sha512-bQC8BnEkxqG8HBGKwG9wXlZqg37RKSMY7v/X8VEWD8JG2JuTHuNK0VFvMPMUKQcbk6B+tf05k+4AShAEtCtJ/w==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/utils/-/utils-8.18.0.tgz",
+      "integrity": "sha512-p6GLdY383i7h5b0Qrfbix3Vc3+J2k6QWw6UMUeY5JGfm3C5LbZ4QIZzJNoNOfgyRe0uuYKjvVOsO/jD4SJO+xg==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
         "@eslint-community/eslint-utils": "^4.4.0",
-        "@typescript-eslint/scope-manager": "8.17.0",
-        "@typescript-eslint/types": "8.17.0",
-        "@typescript-eslint/typescript-estree": "8.17.0"
+        "@typescript-eslint/scope-manager": "8.18.0",
+        "@typescript-eslint/types": "8.18.0",
+        "@typescript-eslint/typescript-estree": "8.18.0"
       },
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
@@ -1392,21 +1386,18 @@
         "url": "https://opencollective.com/typescript-eslint"
       },
       "peerDependencies": {
-        "eslint": "^8.57.0 || ^9.0.0"
-      },
-      "peerDependenciesMeta": {
-        "typescript": {
-          "optional": true
-        }
+        "eslint": "^8.57.0 || ^9.0.0",
+        "typescript": ">=4.8.4 <5.8.0"
       }
     },
     "node_modules/@typescript-eslint/visitor-keys": {
-      "version": "8.17.0",
-      "resolved": "https://registry.npmjs.org/@typescript-eslint/visitor-keys/-/visitor-keys-8.17.0.tgz",
-      "integrity": "sha512-1Hm7THLpO6ww5QU6H/Qp+AusUUl+z/CAm3cNZZ0jQvon9yicgO7Rwd+/WWRpMKLYV6p2UvdbR27c86rzCPpreg==",
+      "version": "8.18.0",
+      "resolved": "https://registry.npmjs.org/@typescript-eslint/visitor-keys/-/visitor-keys-8.18.0.tgz",
+      "integrity": "sha512-pCh/qEA8Lb1wVIqNvBke8UaRjJ6wrAWkJO5yyIbs8Yx6TNGYyfNjOo61tLv+WwLvoLPp4BQ8B7AHKijl8NGUfw==",
       "dev": true,
+      "license": "MIT",
       "dependencies": {
-        "@typescript-eslint/types": "8.17.0",
+        "@typescript-eslint/types": "8.18.0",
         "eslint-visitor-keys": "^4.2.0"
       },
       "engines": {
@@ -1422,6 +1413,7 @@
       "resolved": "https://registry.npmjs.org/eslint-visitor-keys/-/eslint-visitor-keys-4.2.0.tgz",
       "integrity": "sha512-UyLnSehNt62FFhSwjZlHmeokpRK59rcz29j+F1/aDgbkbRTk7wIc9XzdoasMUbRNKDM0qQt/+BJ4BrpFeABemw==",
       "dev": true,
+      "license": "Apache-2.0",
       "engines": {
         "node": "^18.18.0 || ^20.9.0 || >=21.1.0"
       },
@@ -3936,9 +3928,10 @@
       }
     },
     "node_modules/monaco-editor": {
-      "version": "0.52.0",
-      "resolved": "https://registry.npmjs.org/monaco-editor/-/monaco-editor-0.52.0.tgz",
-      "integrity": "sha512-OeWhNpABLCeTqubfqLMXGsqf6OmPU6pHM85kF3dhy6kq5hnhuVS1p3VrEW/XhWHc71P2tHyS5JFySD8mgs1crw=="
+      "version": "0.52.2",
+      "resolved": "https://registry.npmjs.org/monaco-editor/-/monaco-editor-0.52.2.tgz",
+      "integrity": "sha512-GEQWEZmfkOGLdd3XK8ryrfWz3AIP8YymVXiPHEdewrUq7mh0qrKrfHLNCXcbB6sTnMLnOZ3ztSiKcciFUkIJwQ==",
+      "license": "MIT"
     },
     "node_modules/ms": {
       "version": "2.1.3",
@@ -4753,6 +4746,7 @@
       "resolved": "https://registry.npmjs.org/semver/-/semver-7.6.3.tgz",
       "integrity": "sha512-oVekP1cKtI+CTDvHWYFUcMtsK/00wmAEfyqKfNdARm8u1wNVhSgaX7A8d4UuIlUI5e84iEwOhs7ZPYRmzU9U6A==",
       "dev": true,
+      "license": "ISC",
       "bin": {
         "semver": "bin/semver.js"
       },

scripts/_mdformat_utils.py

@@ -1,44 +0,0 @@
-from __future__ import annotations
-
-from typing import TYPE_CHECKING
-
-import mdformat
-
-if TYPE_CHECKING:
-    import argparse
-
-    from markdown_it import MarkdownIt
-    from mdformat.renderer import RenderContext, RenderTreeNode
-
-
-class NoEscapeTextPlugin:
-    r"""Overrides the default text formatting behavior of mdformat.
-
-    By default mdformat will escape any markdown special character found in a
-    text block, e.g., <. Some of these characters are found in our
-    documentation, and when escaped (i.e. \<) will be rendered incorrectly by
-    mkdocs, i.e., the backslash will appear in the render. Because our only
-    purpose in using mdformat is to manage the line-breaks, it makes sense to
-    override its text formatting behavior.
-    """
-
-    def __init__(self: NoEscapeTextPlugin) -> None:
-        self.POSTPROCESSORS = {"text": NoEscapeTextPlugin.text}
-        self.RENDERERS = {}
-
-    @staticmethod
-    def add_cli_options(parser: argparse.ArgumentParser) -> None:
-        pass
-
-    @staticmethod
-    def update_mdit(mdit: MarkdownIt) -> None:
-        pass
-
-    @staticmethod
-    def text(_text: str, node: RenderTreeNode, _context: RenderContext) -> str:
-        return node.content
-
-
-def add_no_escape_text_plugin() -> None:
-    """Add NoEscapeTextPlugin to the list of mdformat extensions."""
-    mdformat.plugins.PARSER_EXTENSIONS["no-escape-text"] = NoEscapeTextPlugin()

scripts/generate_mkdocs.py

@@ -14,8 +14,6 @@ from typing import NamedTuple
 import mdformat
 import yaml
 
-from _mdformat_utils import add_no_escape_text_plugin
-
 
 class Section(NamedTuple):
     """A section to include in the MkDocs documentation."""
@@ -229,12 +227,11 @@ def main() -> None:
 
             f.write(clean_file_content(file_content, title))
 
-    add_no_escape_text_plugin()
     for rule_doc in Path("docs/rules").glob("*.md"):
         # Format rules docs. This has to be completed before adding the meta description
         # otherwise the meta description will be formatted in a way that mkdocs does not
         # support.
-        mdformat.file(rule_doc, extensions=["mkdocs", "admon", "no-escape-text"])
+        mdformat.file(rule_doc, extensions=["mkdocs"])
 
         generate_rule_metadata(rule_doc)