[ty] Make special cases for subscript inference exhaustive

## Summary

Closes https://github.com/astral-sh/ty/issues/2267.

.devcontainer/post-create.sh

@@ -5,4 +5,4 @@ rustup component add clippy rustfmt
 cargo install cargo-insta
 cargo fetch
 
-pip install maturin pre-commit
+pip install maturin prek

.github/CODEOWNERS

@@ -20,9 +20,11 @@
 # ty
 /crates/ty* @carljm @MichaReiser @AlexWaygood @sharkdp @dcreager
 /crates/ruff_db/ @carljm @MichaReiser @sharkdp @dcreager
-/crates/ty_project/ @carljm @MichaReiser @sharkdp @dcreager
-/crates/ty_server/ @carljm @MichaReiser @sharkdp @dcreager
+/crates/ty_project/ @carljm @MichaReiser @sharkdp @dcreager @Gankra
+/crates/ty_ide/ @carljm @MichaReiser @AlexWaygood @sharkdp @dcreager @Gankra
+/crates/ty_server/ @carljm @MichaReiser @sharkdp @dcreager @Gankra
 /crates/ty/ @carljm @MichaReiser @sharkdp @dcreager
-/crates/ty_wasm/ @carljm @MichaReiser @sharkdp @dcreager
+/crates/ty_wasm/ @carljm @MichaReiser @sharkdp @dcreager @Gankra
 /scripts/ty_benchmark/ @carljm @MichaReiser @AlexWaygood @sharkdp @dcreager
-/crates/ty_python_semantic @carljm @AlexWaygood @sharkdp @dcreager
+/crates/ty_python_semantic/ @carljm @AlexWaygood @sharkdp @dcreager
+/crates/ty_module_resolver/ @carljm @MichaReiser @AlexWaygood @Gankra

.github/actionlint.yaml

@@ -1,4 +1,4 @@
-# Configuration for the actionlint tool, which we run via pre-commit
+# Configuration for the actionlint tool, which we run via prek
 # to verify the correctness of the syntax in our GitHub Actions workflows.
 
 self-hosted-runner:
@@ -17,4 +17,4 @@ self-hosted-runner:
 paths:
   ".github/workflows/mypy_primer.yaml":
     ignore:
-      - 'condition "false" is always evaluated to false. remove the if: section'
+      - 'constant expression "false" in condition. remove the if: section'

.github/mypy-primer-ty.toml

@@ -5,5 +5,5 @@
 [rules]
 possibly-unresolved-reference = "warn"
 possibly-missing-import = "warn"
-unused-ignore-comment = "warn"
 division-by-zero = "warn"
+unsupported-dynamic-base = "warn"

.github/renovate.json5

@@ -76,9 +76,9 @@
       enabled: false,
     },
     {
-      groupName: "pre-commit dependencies",
+      groupName: "prek dependencies",
       matchManagers: ["pre-commit"],
-      description: "Weekly update of pre-commit dependencies",
+      description: "Weekly update of prek dependencies",
     },
     {
       groupName: "NPM Development dependencies",

.github/workflows/build-binaries.yml

@@ -51,6 +51,7 @@ jobs:
       - name: "Build sdist"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           command: sdist
           args: --out dist
       - name: "Test sdist"
@@ -81,6 +82,7 @@ jobs:
       - name: "Build wheels - x86_64"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: x86_64
           args: --release --locked --out dist
       - name: "Upload wheels"
@@ -123,6 +125,7 @@ jobs:
       - name: "Build wheels - aarch64"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: aarch64
           args: --release --locked --out dist
       - name: "Test wheel - aarch64"
@@ -179,6 +182,7 @@ jobs:
       - name: "Build wheels"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: ${{ matrix.platform.target }}
           args: --release --locked --out dist
         env:
@@ -232,6 +236,7 @@ jobs:
       - name: "Build wheels"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: ${{ matrix.target }}
           manylinux: auto
           args: --release --locked --out dist
@@ -308,6 +313,7 @@ jobs:
       - name: "Build wheels"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: ${{ matrix.platform.target }}
           manylinux: auto
           docker-options: ${{ matrix.platform.maturin_docker_options }}
@@ -374,6 +380,7 @@ jobs:
       - name: "Build wheels"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: ${{ matrix.target }}
           manylinux: musllinux_1_2
           args: --release --locked --out dist
@@ -439,6 +446,7 @@ jobs:
       - name: "Build wheels"
         uses: PyO3/maturin-action@86b9d133d34bc1b40018696f782949dac11bd380 # v1.49.4
         with:
+          maturin-version: v1.9.6
           target: ${{ matrix.platform.target }}
           manylinux: musllinux_1_2
           args: --release --locked --out dist

.github/workflows/build-wasm.yml

@@ -0,0 +1,58 @@
+# Build ruff_wasm for npm.
+#
+# Assumed to run as a subworkflow of .github/workflows/release.yml; specifically, as a local
+# artifacts job within `cargo-dist`.
+name: "Build wasm"
+
+on:
+  workflow_call:
+    inputs:
+      plan:
+        required: true
+        type: string
+  pull_request:
+    paths:
+      - .github/workflows/build-wasm.yml
+
+concurrency:
+  group: ${{ github.workflow }}-${{ github.ref }}
+  cancel-in-progress: true
+
+permissions: {}
+
+env:
+  CARGO_INCREMENTAL: 0
+  CARGO_NET_RETRY: 10
+  CARGO_TERM_COLOR: always
+  RUSTUP_MAX_RETRIES: 10
+
+jobs:
+  build:
+    if: ${{ !contains(github.event.pull_request.labels.*.name, 'no-build') }}
+    runs-on: ubuntu-latest
+    strategy:
+      matrix:
+        target: [web, bundler, nodejs]
+      fail-fast: false
+    steps:
+      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+        with:
+          persist-credentials: false
+      - name: "Install Rust toolchain"
+        run: rustup target add wasm32-unknown-unknown
+      - uses: jetli/wasm-pack-action@0d096b08b4e5a7de8c28de67e11e945404e9eefa # v0.4.0
+        with:
+          version: v0.13.1
+      - uses: jetli/wasm-bindgen-action@20b33e20595891ab1a0ed73145d8a21fc96e7c29 # v0.2.0
+      - name: "Run wasm-pack build"
+        run: wasm-pack build --target ${{ matrix.target }} crates/ruff_wasm
+      - name: "Rename generated package"
+        run: | # Replace the package name w/ jq
+          jq '.name="@astral-sh/ruff-wasm-${{ matrix.target }}"' crates/ruff_wasm/pkg/package.json > /tmp/package.json
+          mv /tmp/package.json crates/ruff_wasm/pkg
+      - run: cp LICENSE crates/ruff_wasm/pkg # wasm-pack does not put the LICENSE file in the pkg
+      - name: "Upload wasm artifact"
+        uses: actions/upload-artifact@b7c566a772e6b6bfb58ed0dc250532a479d7789f # v6.0.0
+        with:
+          name: artifacts-wasm-${{ matrix.target }}
+          path: crates/ruff_wasm/pkg

.github/workflows/ci.yaml

@@ -281,15 +281,15 @@ jobs:
       - name: "Install mold"
         uses: rui314/setup-mold@725a8794d15fc7563f59595bd9556495c0564878 # v1
       - name: "Install cargo nextest"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-nextest
       - name: "Install cargo insta"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-insta
       - name: "Install uv"
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
           enable-cache: "true"
       - name: ty mdtests (GitHub annotations)
@@ -343,11 +343,11 @@ jobs:
       - name: "Install mold"
         uses: rui314/setup-mold@725a8794d15fc7563f59595bd9556495c0564878 # v1
       - name: "Install cargo nextest"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-nextest
       - name: "Install uv"
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
           enable-cache: "true"
       - name: "Run tests"
@@ -376,11 +376,11 @@ jobs:
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install cargo nextest"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-nextest
       - name: "Install uv"
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
           enable-cache: "true"
       - name: "Run tests"
@@ -486,7 +486,7 @@ jobs:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
         with:
           persist-credentials: false
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           shared-key: ruff-linux-debug
@@ -521,7 +521,7 @@ jobs:
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           save-if: ${{ github.ref == 'refs/heads/main' }}
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - name: "Install Rust toolchain"
         run: rustup component add rustfmt
       # Run all code generation scripts, and verify that the current output is
@@ -561,7 +561,7 @@ jobs:
           ref: ${{ github.event.pull_request.base.ref }}
           persist-credentials: false
 
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
           python-version: ${{ env.PYTHON_VERSION }}
           activate-environment: true
@@ -667,7 +667,7 @@ jobs:
         with:
           fetch-depth: 0
           persist-credentials: false
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           save-if: ${{ github.ref == 'refs/heads/main' }}
@@ -726,7 +726,7 @@ jobs:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
         with:
           persist-credentials: false
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           save-if: ${{ github.ref == 'refs/heads/main' }}
@@ -769,32 +769,29 @@ jobs:
       - name: "Remove wheels from cache"
         run: rm -rf target/wheels
 
-  pre-commit:
-    name: "pre-commit"
+  prek:
+    name: "prek"
     runs-on: ${{ github.repository == 'astral-sh/ruff' && 'depot-ubuntu-22.04-16' || 'ubuntu-latest' }}
     timeout-minutes: 10
     steps:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
         with:
           persist-credentials: false
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
-      - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
-        with:
-          save-if: ${{ github.ref == 'refs/heads/main' }}
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
         with:
           node-version: 24
-      - name: "Cache pre-commit"
+      - name: "Cache prek"
         uses: actions/cache@9255dc7a253b0ccc959486e2bca901246202afeb # v5.0.1
         with:
-          path: ~/.cache/pre-commit
-          key: pre-commit-${{ hashFiles('.pre-commit-config.yaml') }}
-      - name: "Run pre-commit"
+          path: ~/.cache/prek
+          key: prek-${{ hashFiles('.pre-commit-config.yaml') }}
+      - name: "Run prek"
         run: |
           echo '```console' > "$GITHUB_STEP_SUMMARY"
-          # Enable color output for pre-commit and remove it for the summary
-          # Use --hook-stage=manual to enable slower pre-commit hooks that are skipped by default
-          SKIP=cargo-fmt uvx --python="${PYTHON_VERSION}" pre-commit run --all-files --show-diff-on-failure --color=always --hook-stage=manual | \
+          # Enable color output for prek and remove it for the summary
+          # Use --hook-stage=manual to enable slower hooks that are skipped by default
+          SKIP=rustfmt uvx prek run --all-files --show-diff-on-failure --color always --hook-stage manual | \
             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"
@@ -814,7 +811,7 @@ jobs:
       - name: "Install Rust toolchain"
         run: rustup show
       - name: Install uv
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
           python-version: 3.13
           activate-environment: true
@@ -966,13 +963,13 @@ jobs:
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           save-if: ${{ github.ref == 'refs/heads/main' }}
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - name: "Install Rust toolchain"
         run: rustup show
 
       - name: "Install codspeed"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-codspeed
 
@@ -980,7 +977,7 @@ jobs:
         run: cargo codspeed build --features "codspeed,ruff_instrumented" --profile profiling --no-default-features -p ruff_benchmark --bench formatter --bench lexer --bench linter --bench parser
 
       - name: "Run benchmarks"
-        uses: CodSpeedHQ/action@972e3437949c89e1357ebd1a2dbc852fcbc57245 # v4.5.1
+        uses: CodSpeedHQ/action@dbda7111f8ac363564b0c51b992d4ce76bb89f2f # v4.5.2
         with:
           mode: simulation
           run: cargo codspeed run
@@ -1011,7 +1008,7 @@ jobs:
         run: rustup show
 
       - name: "Install codspeed"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-codspeed
 
@@ -1044,10 +1041,10 @@ jobs:
         uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
         with:
           persist-credentials: false
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - name: "Install codspeed"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-codspeed
 
@@ -1061,7 +1058,7 @@ jobs:
         run: chmod +x target/codspeed/simulation/ruff_benchmark/ty
 
       - name: "Run benchmarks"
-        uses: CodSpeedHQ/action@972e3437949c89e1357ebd1a2dbc852fcbc57245 # v4.5.1
+        uses: CodSpeedHQ/action@dbda7111f8ac363564b0c51b992d4ce76bb89f2f # v4.5.2
         with:
           mode: simulation
           run: cargo codspeed run --bench ty "${{ matrix.benchmark }}"
@@ -1092,13 +1089,13 @@ jobs:
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           save-if: ${{ github.ref == 'refs/heads/main' }}
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - name: "Install Rust toolchain"
         run: rustup show
 
       - name: "Install codspeed"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-codspeed
 
@@ -1133,10 +1130,10 @@ jobs:
         with:
           persist-credentials: false
 
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - name: "Install codspeed"
-        uses: taiki-e/install-action@28a9d316db64b78a951f3f8587a5d08cc97ad8eb # v2.65.6
+        uses: taiki-e/install-action@0e76c5c569f13f7eb21e8e5b26fe710062b57b62 # v2.65.13
         with:
           tool: cargo-codspeed
 
@@ -1150,7 +1147,7 @@ jobs:
         run: chmod +x target/codspeed/walltime/ruff_benchmark/ty_walltime
 
       - name: "Run benchmarks"
-        uses: CodSpeedHQ/action@972e3437949c89e1357ebd1a2dbc852fcbc57245 # v4.5.1
+        uses: CodSpeedHQ/action@dbda7111f8ac363564b0c51b992d4ce76bb89f2f # v4.5.2
         env:
           # enabling walltime flamegraphs adds ~6 minutes to the CI time, and they don't
           # appear to provide much useful insight for our walltime benchmarks right now

.github/workflows/daily_fuzz.yaml

@@ -34,7 +34,7 @@ jobs:
       - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
         with:
           persist-credentials: false
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - name: "Install Rust toolchain"
         run: rustup show
       - name: "Install mold"

.github/workflows/mypy_primer.yaml

@@ -48,7 +48,7 @@ jobs:
           persist-credentials: false
 
       - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
@@ -87,7 +87,7 @@ jobs:
           persist-credentials: false
 
       - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
@@ -129,7 +129,7 @@ jobs:
           persist-credentials: false
 
       - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
 
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:

.github/workflows/publish-pypi.yml

@@ -22,7 +22,7 @@ jobs:
       id-token: write
     steps:
       - name: "Install uv"
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
         with:
           pattern: wheels-*

.github/workflows/publish-wasm.yml

@@ -1,25 +1,18 @@
-# Build and publish ruff-api for wasm.
+# Publish ruff_wasm to npm.
 #
 # Assumed to run as a subworkflow of .github/workflows/release.yml; specifically, as a publish
 # job within `cargo-dist`.
-name: "Build and publish wasm"
+name: "Publish wasm"
 
 on:
-  workflow_dispatch:
   workflow_call:
     inputs:
       plan:
         required: true
         type: string
 
-env:
-  CARGO_INCREMENTAL: 0
-  CARGO_NET_RETRY: 10
-  CARGO_TERM_COLOR: always
-  RUSTUP_MAX_RETRIES: 10
-
 jobs:
-  ruff_wasm:
+  publish:
     runs-on: ubuntu-latest
     permissions:
       contents: read
@@ -29,31 +22,19 @@ jobs:
         target: [web, bundler, nodejs]
       fail-fast: false
     steps:
-      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v6.0.1
+      - uses: actions/download-artifact@37930b1c2abaa49bbe596cd826c3c89aef350131 # v7.0.0
         with:
-          persist-credentials: false
-      - name: "Install Rust toolchain"
-        run: rustup target add wasm32-unknown-unknown
-      - uses: jetli/wasm-pack-action@0d096b08b4e5a7de8c28de67e11e945404e9eefa # v0.4.0
-        with:
-          version: v0.13.1
-      - uses: jetli/wasm-bindgen-action@20b33e20595891ab1a0ed73145d8a21fc96e7c29 # v0.2.0
-      - name: "Run wasm-pack build"
-        run: wasm-pack build --target ${{ matrix.target }} crates/ruff_wasm
-      - name: "Rename generated package"
-        run: | # Replace the package name w/ jq
-          jq '.name="@astral-sh/ruff-wasm-${{ matrix.target }}"' crates/ruff_wasm/pkg/package.json > /tmp/package.json
-          mv /tmp/package.json crates/ruff_wasm/pkg
-      - run: cp LICENSE crates/ruff_wasm/pkg # wasm-pack does not put the LICENSE file in the pkg
+          name: artifacts-wasm-${{ matrix.target }}
+          path: pkg
       - uses: actions/setup-node@395ad3262231945c25e8478fd5baf05154b1d79f # v6.1.0
         with:
           node-version: 24
           registry-url: "https://registry.npmjs.org"
       - name: "Publish (dry-run)"
         if: ${{ inputs.plan == '' || fromJson(inputs.plan).announcement_tag_is_implicit }}
-        run: npm publish --dry-run crates/ruff_wasm/pkg
+        run: npm publish --dry-run pkg
       - name: "Publish"
         if: ${{ inputs.plan != '' && !fromJson(inputs.plan).announcement_tag_is_implicit }}
-        run: npm publish --provenance --access public crates/ruff_wasm/pkg
+        run: npm publish --provenance --access public pkg
         env:
           NODE_AUTH_TOKEN: ${{ secrets.NPM_TOKEN }}

.github/workflows/release.yml

@@ -60,7 +60,7 @@ jobs:
     env:
       GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:
-      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
         with:
           persist-credentials: false
           submodules: recursive
@@ -112,18 +112,28 @@ jobs:
       "contents": "read"
       "packages": "write"
 
+  custom-build-wasm:
+    needs:
+      - plan
+    if: ${{ needs.plan.outputs.publishing == 'true' || fromJson(needs.plan.outputs.val).ci.github.pr_run_mode == 'upload' || inputs.tag == 'dry-run' }}
+    uses: ./.github/workflows/build-wasm.yml
+    with:
+      plan: ${{ needs.plan.outputs.val }}
+    secrets: inherit
+
   # Build and package all the platform-agnostic(ish) things
   build-global-artifacts:
     needs:
       - plan
       - custom-build-binaries
       - custom-build-docker
+      - custom-build-wasm
     runs-on: "depot-ubuntu-latest-4"
     env:
       GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
       BUILD_MANIFEST_NAME: target/distrib/global-dist-manifest.json
     steps:
-      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
         with:
           persist-credentials: false
           submodules: recursive
@@ -165,16 +175,17 @@ jobs:
       - plan
       - custom-build-binaries
       - custom-build-docker
+      - custom-build-wasm
       - build-global-artifacts
     # Only run if we're "publishing", and only if plan, local and global didn't fail (skipped is fine)
-    if: ${{ always() && needs.plan.result == 'success' && needs.plan.outputs.publishing == 'true' && (needs.build-global-artifacts.result == 'skipped' || needs.build-global-artifacts.result == 'success') && (needs.custom-build-binaries.result == 'skipped' || needs.custom-build-binaries.result == 'success') && (needs.custom-build-docker.result == 'skipped' || needs.custom-build-docker.result == 'success') }}
+    if: ${{ always() && needs.plan.result == 'success' && needs.plan.outputs.publishing == 'true' && (needs.build-global-artifacts.result == 'skipped' || needs.build-global-artifacts.result == 'success') && (needs.custom-build-binaries.result == 'skipped' || needs.custom-build-binaries.result == 'success') && (needs.custom-build-docker.result == 'skipped' || needs.custom-build-docker.result == 'success') && (needs.custom-build-wasm.result == 'skipped' || needs.custom-build-wasm.result == 'success') }}
     env:
       GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     runs-on: "depot-ubuntu-latest-4"
     outputs:
       val: ${{ steps.host.outputs.manifest }}
     steps:
-      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
         with:
           persist-credentials: false
           submodules: recursive
@@ -250,7 +261,7 @@ jobs:
     env:
       GH_TOKEN: ${{ secrets.GITHUB_TOKEN }}
     steps:
-      - uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd
         with:
           persist-credentials: false
           submodules: recursive

.github/workflows/sync_typeshed.yaml

@@ -76,7 +76,7 @@ jobs:
         run: |
           git config --global user.name typeshedbot
           git config --global user.email '<>'
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - name: Sync typeshed stubs
         run: |
           rm -rf "ruff/${VENDORED_TYPESHED}"
@@ -130,7 +130,7 @@ jobs:
         with:
           persist-credentials: true
           ref: ${{ env.UPSTREAM_BRANCH}}
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - name: Setup git
         run: |
           git config --global user.name typeshedbot
@@ -169,7 +169,7 @@ jobs:
         with:
           persist-credentials: true
           ref: ${{ env.UPSTREAM_BRANCH}}
-      - uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+      - uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
       - name: Setup git
         run: |
           git config --global user.name typeshedbot

.github/workflows/ty-ecosystem-analyzer.yaml

@@ -38,14 +38,14 @@ jobs:
           persist-credentials: false
 
       - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
-          enable-cache: true # zizmor: ignore[cache-poisoning] acceptable risk for CloudFlare pages artifact
+          enable-cache: true
 
       - uses: Swatinem/rust-cache@779680da715d629ac1d338a641029a2f4372abb5 # v2.8.2
         with:
           workspaces: "ruff"
-          lookup-only: false # zizmor: ignore[cache-poisoning] acceptable risk for CloudFlare pages artifact
+          lookup-only: false
 
       - name: Install Rust toolchain
         run: rustup show

.github/workflows/ty-ecosystem-report.yaml

@@ -32,7 +32,7 @@ jobs:
           persist-credentials: false
 
       - name: Install the latest version of uv
-        uses: astral-sh/setup-uv@681c641aba71e4a1c380be3ab5e12ad51f415867 # v7.1.6
+        uses: astral-sh/setup-uv@61cb8a9741eeb8a550a1b8544337180c0fc8476b # v7.2.0
         with:
           enable-cache: true
 

.pre-commit-config.yaml

@@ -21,15 +21,61 @@ exclude: |
   )$
 
 repos:
+  # Priority 0: Read-only hooks; hooks that modify disjoint file types.
   - repo: https://github.com/pre-commit/pre-commit-hooks
     rev: v6.0.0
     hooks:
       - id: check-merge-conflict
+        priority: 0
 
   - repo: https://github.com/abravalheri/validate-pyproject
     rev: v0.24.1
     hooks:
       - id: validate-pyproject
+        priority: 0
+
+  - repo: https://github.com/crate-ci/typos
+    rev: v1.41.0
+    hooks:
+      - id: typos
+        priority: 0
+
+  - repo: local
+    hooks:
+      - id: rustfmt
+        name: rustfmt
+        entry: rustfmt
+        language: system
+        types: [rust]
+        priority: 0
+
+  # Prettier
+  - repo: https://github.com/rbubley/mirrors-prettier
+    rev: v3.7.4
+    hooks:
+      - id: prettier
+        types: [yaml]
+        priority: 0
+
+  # zizmor detects security vulnerabilities in GitHub Actions workflows.
+  # Additional configuration for the tool is found in `.github/zizmor.yml`
+  - repo: https://github.com/zizmorcore/zizmor-pre-commit
+    rev: v1.19.0
+    hooks:
+      - id: zizmor
+        priority: 0
+
+  - repo: https://github.com/python-jsonschema/check-jsonschema
+    rev: 0.36.0
+    hooks:
+      - id: check-github-workflows
+        priority: 0
+
+  - repo: https://github.com/shellcheck-py/shellcheck-py
+    rev: v0.11.0.1
+    hooks:
+      - id: shellcheck
+        priority: 0
 
   - repo: https://github.com/executablebooks/mdformat
     rev: 1.0.0
@@ -44,7 +90,20 @@ repos:
             docs/formatter/black\.md
             | docs/\w+\.md
           )$
+        priority: 0
 
+  - repo: https://github.com/astral-sh/ruff-pre-commit
+    rev: v0.14.10
+    hooks:
+      - id: ruff-format
+        priority: 0
+      - id: ruff-check
+        args: [--fix, --exit-non-zero-on-fix]
+        types_or: [python, pyi]
+        require_serial: true
+        priority: 1
+
+  # Priority 1: Second-pass fixers (e.g., markdownlint-fix runs after mdformat).
   - repo: https://github.com/igorshubovych/markdownlint-cli
     rev: v0.47.0
     hooks:
@@ -54,7 +113,9 @@ repos:
             docs/formatter/black\.md
             | docs/\w+\.md
           )$
+        priority: 1
 
+  # Priority 2: blacken-docs runs after markdownlint-fix (both modify markdown).
   - repo: https://github.com/adamchainz/blacken-docs
     rev: 1.20.0
     hooks:
@@ -68,70 +129,26 @@ repos:
           )$
         additional_dependencies:
           - black==25.12.0
-
-  - repo: https://github.com/crate-ci/typos
-    rev: v1.40.0
-    hooks:
-      - id: typos
-
-  - repo: local
-    hooks:
-      - id: cargo-fmt
-        name: cargo fmt
-        entry: cargo fmt --
-        language: system
-        types: [rust]
-        pass_filenames: false # This makes it a lot faster
-
-  - repo: https://github.com/astral-sh/ruff-pre-commit
-    rev: v0.14.10
-    hooks:
-      - id: ruff-format
-      - id: ruff-check
-        args: [--fix, --exit-non-zero-on-fix]
-        types_or: [python, pyi]
-        require_serial: true
-
-  # Prettier
-  - repo: https://github.com/rbubley/mirrors-prettier
-    rev: v3.7.4
-    hooks:
-      - 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/zizmorcore/zizmor-pre-commit
-    rev: v1.19.0
-    hooks:
-      - id: zizmor
-
-  - repo: https://github.com/python-jsonschema/check-jsonschema
-    rev: 0.36.0
-    hooks:
-      - id: check-github-workflows
+        priority: 2
 
   # `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: v1.7.9
+    rev: v1.7.10
     hooks:
       - id: actionlint
         stages:
           # This hook is disabled by default, since it's quite slow.
-          # To run all hooks *including* this hook, use `uvx pre-commit run -a --hook-stage=manual`.
-          # To run *just* this hook, use `uvx pre-commit run -a actionlint --hook-stage=manual`.
+          # To run all hooks *including* this hook, use `uvx prek run -a --hook-stage=manual`.
+          # To run *just* this hook, use `uvx prek run -a actionlint --hook-stage=manual`.
           - manual
         args:
           - "-ignore=SC2129" # ignorable stylistic lint from shellcheck
           - "-ignore=SC2016" # another shellcheck lint: seems to have false positives?
+        language: golang # means renovate will also update `additional_dependencies`
         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@v0.11.1"
-
-  - repo: https://github.com/shellcheck-py/shellcheck-py
-    rev: v0.11.0.1
-    hooks:
-      - id: shellcheck
+        priority: 0

CHANGELOG.md

@@ -1,5 +1,63 @@
 # Changelog
 
+## 0.14.11
+
+Released on 2026-01-08.
+
+### Preview features
+
+- Consolidate diagnostics for matched disable/enable suppression comments ([#22099](https://github.com/astral-sh/ruff/pull/22099))
+- Report diagnostics for invalid/unmatched range suppression comments ([#21908](https://github.com/astral-sh/ruff/pull/21908))
+- \[`airflow`\] Passing positional argument into `airflow.lineage.hook.HookLineageCollector.create_asset` is not allowed (`AIR303`) ([#22046](https://github.com/astral-sh/ruff/pull/22046))
+- \[`refurb`\] Mark `FURB192` fix as always unsafe ([#22210](https://github.com/astral-sh/ruff/pull/22210))
+- \[`ruff`\] Add `non-empty-init-module` (`RUF067`) ([#22143](https://github.com/astral-sh/ruff/pull/22143))
+
+### Bug fixes
+
+- Fix GitHub format for multi-line diagnostics ([#22108](https://github.com/astral-sh/ruff/pull/22108))
+- \[`flake8-unused-arguments`\] Mark `**kwargs` in `TypeVar` as used (`ARG001`) ([#22214](https://github.com/astral-sh/ruff/pull/22214))
+
+### Rule changes
+
+- Add `help:` subdiagnostics for several Ruff rules that can sometimes appear to disagree with `ty` ([#22331](https://github.com/astral-sh/ruff/pull/22331))
+- \[`pylint`\] Demote `PLW1510` fix to display-only ([#22318](https://github.com/astral-sh/ruff/pull/22318))
+- \[`pylint`\] Ignore identical members (`PLR1714`) ([#22220](https://github.com/astral-sh/ruff/pull/22220))
+- \[`pylint`\] Improve diagnostic range for `PLC0206` ([#22312](https://github.com/astral-sh/ruff/pull/22312))
+- \[`ruff`\] Improve fix title for `RUF102` invalid rule code ([#22100](https://github.com/astral-sh/ruff/pull/22100))
+- \[`flake8-simplify`\]: Avoid unnecessary builtins import for `SIM105` ([#22358](https://github.com/astral-sh/ruff/pull/22358))
+
+### Configuration
+
+- Allow Python 3.15 as valid `target-version` value in preview ([#22419](https://github.com/astral-sh/ruff/pull/22419))
+- Check `required-version` before parsing rules ([#22410](https://github.com/astral-sh/ruff/pull/22410))
+- Include configured `src` directories when resolving graphs ([#22451](https://github.com/astral-sh/ruff/pull/22451))
+
+### Documentation
+
+- Update `T201` suggestion to not use root logger to satisfy `LOG015` ([#22059](https://github.com/astral-sh/ruff/pull/22059))
+- Fix `iter` example in unsafe fixes doc ([#22118](https://github.com/astral-sh/ruff/pull/22118))
+- \[`flake8_print`\] better suggestion for `basicConfig` in `T201` docs ([#22101](https://github.com/astral-sh/ruff/pull/22101))
+- \[`pylint`\] Restore the fix safety docs for `PLW0133` ([#22211](https://github.com/astral-sh/ruff/pull/22211))
+- Fix Jupyter notebook discovery info for editors ([#22447](https://github.com/astral-sh/ruff/pull/22447))
+
+### Contributors
+
+- [@charliermarsh](https://github.com/charliermarsh)
+- [@ntBre](https://github.com/ntBre)
+- [@cenviity](https://github.com/cenviity)
+- [@njhearp](https://github.com/njhearp)
+- [@cbachhuber](https://github.com/cbachhuber)
+- [@jelle-openai](https://github.com/jelle-openai)
+- [@AlexWaygood](https://github.com/AlexWaygood)
+- [@ValdonVitija](https://github.com/ValdonVitija)
+- [@BurntSushi](https://github.com/BurntSushi)
+- [@Jkhall81](https://github.com/Jkhall81)
+- [@PeterJCLaw](https://github.com/PeterJCLaw)
+- [@harupy](https://github.com/harupy)
+- [@amyreese](https://github.com/amyreese)
+- [@sjyangkevin](https://github.com/sjyangkevin)
+- [@woodruffw](https://github.com/woodruffw)
+
 ## 0.14.10
 
 Released on 2025-12-18.

CLAUDE.md

@@ -10,6 +10,12 @@ Run all tests (using `nextest` for faster execution):
 cargo nextest run
 ```
 
+For faster test execution, use the `fast-test` profile which enables optimizations while retaining debug info:
+
+```sh
+cargo nextest run --cargo-profile fast-test
+```
+
 Run tests for a specific crate:
 
 ```sh
@@ -59,6 +65,7 @@ When working on ty, PR titles should start with `[ty]` and be tagged with the `t
 - All changes must be tested. If you're not testing your changes, you're not done.
 - Get your tests to pass. If you didn't run the tests, your code does not work.
 - Follow existing code style. Check neighboring files for patterns.
-- Always run `uvx pre-commit run -a` at the end of a task.
+- Always run `uvx prek run -a` at the end of a task.
 - Avoid writing significant amounts of new code. This is often a sign that we're missing an existing method or mechanism that could help solve the problem. Look for existing utilities first.
 - Avoid falling back to patterns that require `panic!`, `unreachable!`, or `.unwrap()`. Instead, try to encode those constraints in the type system.
+- Prefer let chains (`if let` combined with `&&`) over nested `if let` statements to reduce indentation and improve readability.

CONTRIBUTING.md

@@ -53,12 +53,12 @@ cargo install cargo-insta
 You'll need [uv](https://docs.astral.sh/uv/getting-started/installation/) (or `pipx` and `pip`) to
 run Python utility commands.
 
-You can optionally install pre-commit hooks to automatically run the validation checks
+You can optionally install hooks to automatically run the validation checks
 when making a commit:
 
 ```shell
-uv tool install pre-commit
-pre-commit install
+uv tool install prek
+prek install
 ```
 
 We recommend [nextest](https://nexte.st/) to run Ruff's test suite (via `cargo nextest run`),
@@ -85,7 +85,7 @@ and that it passes both the lint and test validation checks:
 ```shell
 cargo clippy --workspace --all-targets --all-features -- -D warnings  # Rust linting
 RUFF_UPDATE_SCHEMA=1 cargo test  # Rust testing and updating ruff.schema.json
-uvx pre-commit run --all-files --show-diff-on-failure  # Rust and Python formatting, Markdown and Python linting, etc.
+uvx prek run -a  # Rust and Python formatting, Markdown and Python linting, etc.
 ```
 
 These checks will run on GitHub Actions when you open your pull request, but running them locally
@@ -381,7 +381,7 @@ Commit each step of this process separately for easier review.
 
     - Often labels will be missing from pull requests they will need to be manually organized into the proper section
     - Changes should be edited to be user-facing descriptions, avoiding internal details
-    - Square brackets (eg, `[ruff]` project name) will be automatically escaped by `pre-commit`
+    - Square brackets (eg, `[ruff]` project name) will be automatically escaped by `prek`
 
     Additionally, for minor releases:
 

Cargo.lock

@@ -466,9 +466,9 @@ dependencies = [
 
 [[package]]
 name = "clap"
-version = "4.5.53"
+version = "4.5.54"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "c9e340e012a1bf4935f5282ed1436d1489548e8f72308207ea5df0e23d2d03f8"
+checksum = "c6e6ff9dcd79cff5cd969a17a545d79e84ab086e444102a591e288a8aa3ce394"
 dependencies = [
  "clap_builder",
  "clap_derive",
@@ -476,9 +476,9 @@ dependencies = [
 
 [[package]]
 name = "clap_builder"
-version = "4.5.53"
+version = "4.5.54"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "d76b5d13eaa18c901fd2f7fca939fefe3a0727a953561fefdf3b2922b8569d00"
+checksum = "fa42cf4d2b7a41bc8f663a7cab4031ebafa1bf3875705bfaf8466dc60ab52c00"
 dependencies = [
  "anstream",
  "anstyle",
@@ -1583,11 +1583,11 @@ dependencies = [
 
 [[package]]
 name = "imperative"
-version = "1.0.6"
+version = "1.0.7"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "29a1f6526af721f9aec9ceed7ab8ebfca47f3399d08b80056c2acca3fcb694a9"
+checksum = "35e1d0bd9c575c52e59aad8e122a11786e852a154678d0c86e9e243d55273970"
 dependencies = [
- "phf",
+ "phf 0.13.1",
  "rust-stemmers",
 ]
 
@@ -1648,9 +1648,9 @@ dependencies = [
 
 [[package]]
 name = "insta"
-version = "1.45.1"
+version = "1.46.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "983e3b24350c84ab8a65151f537d67afbbf7153bb9f1110e03e9fa9b07f67a5c"
+checksum = "1b66886d14d18d420ab5052cbff544fc5d34d0b2cdd35eb5976aaa10a4a472e5"
 dependencies = [
  "console 0.15.11",
  "once_cell",
@@ -1874,9 +1874,9 @@ checksum = "bbd2bcb4c963f2ddae06a2efc7e9f3591312473c50c6685e1f298068316e66fe"
 
 [[package]]
 name = "libc"
-version = "0.2.178"
+version = "0.2.179"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "37c93d8daa9d8a012fd8ab92f088405fb202ea0b6ab73ee2482ae66af4f42091"
+checksum = "c5a2d376baa530d1238d133232d15e239abad80d05838b4b59354e5268af431f"
 
 [[package]]
 name = "libcst"
@@ -2488,7 +2488,17 @@ version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "1fd6780a80ae0c52cc120a26a1a42c1ae51b247a253e4e06113d23d2c2edd078"
 dependencies = [
- "phf_shared",
+ "phf_shared 0.11.3",
+]
+
+[[package]]
+name = "phf"
+version = "0.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "c1562dc717473dbaa4c1f85a36410e03c047b2e7df7f45ee938fbef64ae7fadf"
+dependencies = [
+ "phf_shared 0.13.1",
+ "serde",
 ]
 
 [[package]]
@@ -2498,7 +2508,7 @@ source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "aef8048c789fa5e851558d709946d6d79a8ff88c0440c587967f8e94bfb1216a"
 dependencies = [
  "phf_generator",
- "phf_shared",
+ "phf_shared 0.11.3",
 ]
 
 [[package]]
@@ -2507,7 +2517,7 @@ version = "0.11.3"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "3c80231409c20246a13fddb31776fb942c38553c51e871f8cbd687a4cfb5843d"
 dependencies = [
- "phf_shared",
+ "phf_shared 0.11.3",
  "rand 0.8.5",
 ]
 
@@ -2520,6 +2530,15 @@ dependencies = [
  "siphasher",
 ]
 
+[[package]]
+name = "phf_shared"
+version = "0.13.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "e57fef6bc5981e38c2ce2d63bfa546861309f875b8a75f092d1d54ae2d64f266"
+dependencies = [
+ "siphasher",
+]
+
 [[package]]
 name = "pin-project-lite"
 version = "0.2.16"
@@ -2912,7 +2931,7 @@ dependencies = [
 
 [[package]]
 name = "ruff"
-version = "0.14.10"
+version = "0.14.11"
 dependencies = [
  "anyhow",
  "argfile",
@@ -2928,6 +2947,7 @@ dependencies = [
  "filetime",
  "globwalk",
  "ignore",
+ "indexmap",
  "indoc",
  "insta",
  "insta-cmd",
@@ -3171,7 +3191,7 @@ dependencies = [
 
 [[package]]
 name = "ruff_linter"
-version = "0.14.10"
+version = "0.14.11"
 dependencies = [
  "aho-corasick",
  "anyhow",
@@ -3285,7 +3305,6 @@ dependencies = [
  "compact_str",
  "get-size2",
  "is-macro",
- "itertools 0.14.0",
  "memchr",
  "ruff_cache",
  "ruff_macros",
@@ -3529,7 +3548,7 @@ dependencies = [
 
 [[package]]
 name = "ruff_wasm"
-version = "0.14.10"
+version = "0.14.11"
 dependencies = [
  "console_error_panic_hook",
  "console_log",
@@ -3645,7 +3664,7 @@ checksum = "28d3b2b1366ec20994f1fd18c3c594f05c5dd4bc44d8bb0c1c632c8d6829481f"
 [[package]]
 name = "salsa"
 version = "0.25.2"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=309c249088fdeef0129606fa34ec2eefc74736ff#309c249088fdeef0129606fa34ec2eefc74736ff"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=9860ff6ca0f1f8f3a8d6b832020002790b501254#9860ff6ca0f1f8f3a8d6b832020002790b501254"
 dependencies = [
  "boxcar",
  "compact_str",
@@ -3670,12 +3689,12 @@ dependencies = [
 [[package]]
 name = "salsa-macro-rules"
 version = "0.25.2"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=309c249088fdeef0129606fa34ec2eefc74736ff#309c249088fdeef0129606fa34ec2eefc74736ff"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=9860ff6ca0f1f8f3a8d6b832020002790b501254#9860ff6ca0f1f8f3a8d6b832020002790b501254"
 
 [[package]]
 name = "salsa-macros"
 version = "0.25.2"
-source = "git+https://github.com/salsa-rs/salsa.git?rev=309c249088fdeef0129606fa34ec2eefc74736ff#309c249088fdeef0129606fa34ec2eefc74736ff"
+source = "git+https://github.com/salsa-rs/salsa.git?rev=9860ff6ca0f1f8f3a8d6b832020002790b501254#9860ff6ca0f1f8f3a8d6b832020002790b501254"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -3993,9 +4012,9 @@ checksum = "e396b6523b11ccb83120b115a0b7366de372751aa6edf19844dfb13a6af97e91"
 
 [[package]]
 name = "syn"
-version = "2.0.111"
+version = "2.0.113"
 source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "390cc9a294ab71bdb1aa2e99d13be9c753cd2d7bd6560c77118597410c4d2e87"
+checksum = "678faa00651c9eb72dd2020cbdf275d92eccb2400d568e419efdd64838145cb4"
 dependencies = [
  "proc-macro2",
  "quote",
@@ -4059,7 +4078,7 @@ checksum = "d4ea810f0692f9f51b382fff5893887bb4580f5fa246fde546e0b13e7fcee662"
 dependencies = [
  "fnv",
  "nom",
- "phf",
+ "phf 0.11.3",
  "phf_codegen",
 ]
 
@@ -4443,6 +4462,7 @@ version = "0.0.0"
 dependencies = [
  "bitflags 2.10.0",
  "camino",
+ "compact_str",
  "get-size2",
  "insta",
  "itertools 0.14.0",
@@ -4511,11 +4531,13 @@ dependencies = [
  "regex-automata",
  "ruff_cache",
  "ruff_db",
+ "ruff_diagnostics",
  "ruff_macros",
  "ruff_memory_usage",
  "ruff_options_metadata",
  "ruff_python_ast",
  "ruff_python_formatter",
+ "ruff_python_trivia",
  "ruff_text_size",
  "rustc-hash",
  "salsa",
@@ -4804,7 +4826,7 @@ version = "1.3.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "d1673eca9782c84de5f81b82e4109dcfb3611c8ba0d52930ec4a9478f547b2dd"
 dependencies = [
- "phf",
+ "phf 0.11.3",
  "unicode_names2_generator",
 ]
 

Cargo.toml

@@ -150,7 +150,7 @@ regex-automata = { version = "0.4.9" }
 rustc-hash = { version = "2.0.0" }
 rustc-stable-hash = { version = "0.1.2" }
 # When updating salsa, make sure to also update the revision in `fuzz/Cargo.toml`
-salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "309c249088fdeef0129606fa34ec2eefc74736ff", default-features = false, features = [
+salsa = { git = "https://github.com/salsa-rs/salsa.git", rev = "9860ff6ca0f1f8f3a8d6b832020002790b501254", default-features = false, features = [
     "compact_str",
     "macros",
     "salsa_unstable",
@@ -335,6 +335,11 @@ strip = false
 debug = "full"
 lto = false
 
+# Profile for faster iteration: applies minimal optimizations for faster tests.
+[profile.fast-test]
+inherits = "dev"
+opt-level = 1
+
 # The profile that 'cargo dist' will build with.
 [profile.dist]
 inherits = "release"

README.md

@@ -150,8 +150,8 @@ curl -LsSf https://astral.sh/ruff/install.sh | sh
 powershell -c "irm https://astral.sh/ruff/install.ps1 | iex"
 
 # For a specific version.
-curl -LsSf https://astral.sh/ruff/0.14.10/install.sh | sh
-powershell -c "irm https://astral.sh/ruff/0.14.10/install.ps1 | iex"
+curl -LsSf https://astral.sh/ruff/0.14.11/install.sh | sh
+powershell -c "irm https://astral.sh/ruff/0.14.11/install.ps1 | iex"
 ```
 
 You can also install Ruff via [Homebrew](https://formulae.brew.sh/formula/ruff), [Conda](https://anaconda.org/conda-forge/ruff),
@@ -184,7 +184,7 @@ Ruff can also be used as a [pre-commit](https://pre-commit.com/) hook via [`ruff
 ```yaml
 - repo: https://github.com/astral-sh/ruff-pre-commit
   # Ruff version.
-  rev: v0.14.10
+  rev: v0.14.11
   hooks:
     # Run the linter.
     - id: ruff-check

crates/ruff/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff"
-version = "0.14.10"
+version = "0.14.11"
 publish = true
 authors = { workspace = true }
 edition = { workspace = true }
@@ -48,6 +48,7 @@ colored = { workspace = true }
 filetime = { workspace = true }
 globwalk = { workspace = true }
 ignore = { workspace = true }
+indexmap = { workspace = true }
 is-macro = { workspace = true }
 itertools = { workspace = true }
 jiff = { workspace = true }

crates/ruff/src/commands/analyze_graph.rs

@@ -2,6 +2,7 @@ use crate::args::{AnalyzeGraphArgs, ConfigArguments};
 use crate::resolve::resolve;
 use crate::{ExitStatus, resolve_default_files};
 use anyhow::Result;
+use indexmap::IndexSet;
 use log::{debug, warn};
 use path_absolutize::CWD;
 use ruff_db::system::{SystemPath, SystemPathBuf};
@@ -11,7 +12,7 @@ use ruff_linter::source_kind::SourceKind;
 use ruff_linter::{warn_user, warn_user_once};
 use ruff_python_ast::{PySourceType, SourceType};
 use ruff_workspace::resolver::{ResolvedFile, match_exclusion, python_files_in_path};
-use rustc_hash::FxHashMap;
+use rustc_hash::{FxBuildHasher, FxHashMap};
 use std::io::Write;
 use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
@@ -59,17 +60,34 @@ pub(crate) fn analyze_graph(
         })
         .collect::<FxHashMap<_, _>>();
 
-    // Create a database from the source roots.
-    let src_roots = package_roots
-        .values()
-        .filter_map(|package| package.as_deref())
-        .filter_map(|package| package.parent())
-        .map(Path::to_path_buf)
-        .filter_map(|path| SystemPathBuf::from_path_buf(path).ok())
-        .collect();
+    // Create a database from the source roots, combining configured `src` paths with detected
+    // package roots. Configured paths are added first so they take precedence, and duplicates
+    // are removed.
+    let mut src_roots: IndexSet<SystemPathBuf, FxBuildHasher> = IndexSet::default();
+
+    // Add configured `src` paths first (for precedence), filtering to only include existing
+    // directories.
+    src_roots.extend(
+        pyproject_config
+            .settings
+            .linter
+            .src
+            .iter()
+            .filter(|path| path.is_dir())
+            .filter_map(|path| SystemPathBuf::from_path_buf(path.clone()).ok()),
+    );
+
+    // Add detected package roots.
+    src_roots.extend(
+        package_roots
+            .values()
+            .filter_map(|package| package.as_deref())
+            .filter_map(|path| path.parent())
+            .filter_map(|path| SystemPathBuf::from_path_buf(path.to_path_buf()).ok()),
+    );
 
     let db = ModuleDb::from_src_roots(
-        src_roots,
+        src_roots.into_iter().collect(),
         pyproject_config
             .settings
             .analyze

crates/ruff/src/commands/show_settings.rs

@@ -29,10 +29,10 @@ pub(crate) fn show_settings(
         bail!("No files found under the given path");
     };
 
-    let settings = resolver.resolve(&path);
+    let (settings, config_path) = resolver.resolve_with_path(&path);
 
     writeln!(writer, "Resolved settings for: \"{}\"", path.display())?;
-    if let Some(settings_path) = pyproject_config.path.as_ref() {
+    if let Some(settings_path) = config_path {
         writeln!(writer, "Settings path: \"{}\"", settings_path.display())?;
     }
     write!(writer, "{settings}")?;

crates/ruff/tests/analyze_graph.rs

@@ -714,6 +714,121 @@ fn notebook_basic() -> Result<()> {
     Ok(())
 }
 
+/// Test that the `src` configuration option is respected.
+///
+/// This is useful for monorepos where there are multiple source directories that need to be
+/// included in the module resolution search path.
+#[test]
+fn src_option() -> Result<()> {
+    let tempdir = TempDir::new()?;
+    let root = ChildPath::new(tempdir.path());
+
+    // Create a lib directory with a package.
+    root.child("lib")
+        .child("mylib")
+        .child("__init__.py")
+        .write_str("def helper(): pass")?;
+
+    // Create an app directory with a file that imports from mylib.
+    root.child("app").child("__init__.py").write_str("")?;
+    root.child("app")
+        .child("main.py")
+        .write_str("from mylib import helper")?;
+
+    // Without src configured, the import from mylib won't resolve.
+    insta::with_settings!({
+        filters => INSTA_FILTERS.to_vec(),
+    }, {
+        assert_cmd_snapshot!(command().arg("app").current_dir(&root), @r#"
+        success: true
+        exit_code: 0
+        ----- stdout -----
+        {
+          "app/__init__.py": [],
+          "app/main.py": []
+        }
+
+        ----- stderr -----
+        "#);
+    });
+
+    // With src = ["lib"], the import should resolve.
+    root.child("ruff.toml").write_str(indoc::indoc! {r#"
+        src = ["lib"]
+    "#})?;
+
+    insta::with_settings!({
+        filters => INSTA_FILTERS.to_vec(),
+    }, {
+        assert_cmd_snapshot!(command().arg("app").current_dir(&root), @r#"
+        success: true
+        exit_code: 0
+        ----- stdout -----
+        {
+          "app/__init__.py": [],
+          "app/main.py": [
+            "lib/mylib/__init__.py"
+          ]
+        }
+
+        ----- stderr -----
+        "#);
+    });
+
+    Ok(())
+}
+
+/// Test that glob patterns in `src` are expanded.
+#[test]
+fn src_glob_expansion() -> Result<()> {
+    let tempdir = TempDir::new()?;
+    let root = ChildPath::new(tempdir.path());
+
+    // Create multiple lib directories with packages.
+    root.child("libs")
+        .child("lib_a")
+        .child("pkg_a")
+        .child("__init__.py")
+        .write_str("def func_a(): pass")?;
+    root.child("libs")
+        .child("lib_b")
+        .child("pkg_b")
+        .child("__init__.py")
+        .write_str("def func_b(): pass")?;
+
+    // Create an app that imports from both packages.
+    root.child("app").child("__init__.py").write_str("")?;
+    root.child("app")
+        .child("main.py")
+        .write_str("from pkg_a import func_a\nfrom pkg_b import func_b")?;
+
+    // Use a glob pattern to include all lib directories.
+    root.child("ruff.toml").write_str(indoc::indoc! {r#"
+        src = ["libs/*"]
+    "#})?;
+
+    insta::with_settings!({
+        filters => INSTA_FILTERS.to_vec(),
+    }, {
+        assert_cmd_snapshot!(command().arg("app").current_dir(&root), @r#"
+        success: true
+        exit_code: 0
+        ----- stdout -----
+        {
+          "app/__init__.py": [],
+          "app/main.py": [
+            "libs/lib_a/pkg_a/__init__.py",
+            "libs/lib_b/pkg_b/__init__.py"
+          ]
+        }
+
+        ----- stderr -----
+        "#);
+    });
+
+    Ok(())
+}
+
 #[test]
 fn notebook_with_magic() -> Result<()> {
     let tempdir = TempDir::new()?;

crates/ruff/tests/cli/lint.rs

@@ -1126,6 +1126,35 @@ import os
     Ok(())
 }
 
+#[test]
+fn required_version_fails_to_parse() -> Result<()> {
+    let fixture = CliTest::with_file(
+        "ruff.toml",
+        r#"
+required-version = "pikachu"
+"#,
+    )?;
+    assert_cmd_snapshot!(fixture
+        .check_command(), @r#"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    ruff failed
+      Cause: Failed to load configuration `[TMP]/ruff.toml`
+      Cause: Failed to parse [TMP]/ruff.toml
+      Cause: TOML parse error at line 2, column 20
+      |
+    2 | required-version = "pikachu"
+      |                    ^^^^^^^^^
+    Failed to parse version: Unexpected end of version specifier, expected operator:
+    pikachu
+    ^^^^^^^
+    "#);
+    Ok(())
+}
+
 #[test]
 fn required_version_exact_mismatch() -> Result<()> {
     let version = env!("CARGO_PKG_VERSION");
@@ -1137,10 +1166,10 @@ required-version = "0.1.0"
 "#,
     )?;
 
-    insta::with_settings!({
-        filters => vec![(version, "[VERSION]")]
-    }, {
-    assert_cmd_snapshot!(fixture
+    let mut settings = insta::Settings::clone_current();
+    settings.add_filter(version, "[VERSION]");
+    settings.bind(|| {
+        assert_cmd_snapshot!(fixture
         .check_command()
         .arg("--config")
         .arg("ruff.toml")
@@ -1154,6 +1183,7 @@ import os
 
     ----- stderr -----
     ruff failed
+      Cause: Failed to load configuration `[TMP]/ruff.toml`
       Cause: Required version `==0.1.0` does not match the running version `[VERSION]`
     ");
     });
@@ -1212,10 +1242,10 @@ required-version = ">{version}"
         ),
     )?;
 
-    insta::with_settings!({
-        filters => vec![(version, "[VERSION]")]
-    }, {
-    assert_cmd_snapshot!(fixture
+    let mut settings = insta::Settings::clone_current();
+    settings.add_filter(version, "[VERSION]");
+    settings.bind(|| {
+        assert_cmd_snapshot!(fixture
         .check_command()
         .arg("--config")
         .arg("ruff.toml")
@@ -1229,6 +1259,48 @@ import os
 
     ----- stderr -----
     ruff failed
+      Cause: Failed to load configuration `[TMP]/ruff.toml`
+      Cause: Required version `>[VERSION]` does not match the running version `[VERSION]`
+    ");
+    });
+
+    Ok(())
+}
+
+#[test]
+fn required_version_precedes_rule_validation() -> Result<()> {
+    let version = env!("CARGO_PKG_VERSION");
+
+    let fixture = CliTest::with_file(
+        "ruff.toml",
+        &format!(
+            r#"
+required-version = ">{version}"
+
+[lint]
+select = ["RUF999"]
+"#
+        ),
+    )?;
+
+    let mut settings = insta::Settings::clone_current();
+    settings.add_filter(version, "[VERSION]");
+    settings.bind(|| {
+        assert_cmd_snapshot!(fixture
+        .check_command()
+        .arg("--config")
+        .arg("ruff.toml")
+        .arg("-")
+        .pass_stdin(r#"
+import os
+"#), @"
+    success: false
+    exit_code: 2
+    ----- stdout -----
+
+    ----- stderr -----
+    ruff failed
+      Cause: Failed to load configuration `[TMP]/ruff.toml`
       Cause: Required version `>[VERSION]` does not match the running version `[VERSION]`
     ");
     });

crates/ruff/tests/cli/snapshots/cli__lint__requires_python_pyproject_toml_above_with_tool.snap

@@ -16,6 +16,7 @@ success: true
 exit_code: 0
 ----- stdout -----
 Resolved settings for: "[TMP]/foo/test.py"
+Settings path: "[TMP]/foo/pyproject.toml"
 
 # General Settings
 cache_dir = "[TMP]/foo/.ruff_cache"

crates/ruff/tests/show_settings.rs

@@ -50,6 +50,56 @@ ignore = [
     Ok(())
 }
 
+#[test]
+fn display_settings_from_nested_directory() -> anyhow::Result<()> {
+    let tempdir = TempDir::new().context("Failed to create temp directory.")?;
+
+    // Tempdir path's on macos are symlinks, which doesn't play nicely with
+    // our snapshot filtering.
+    let project_dir =
+        dunce::canonicalize(tempdir.path()).context("Failed to canonical tempdir path.")?;
+
+    // Root pyproject.toml.
+    std::fs::write(
+        project_dir.join("pyproject.toml"),
+        r#"
+[tool.ruff]
+line-length = 100
+
+[tool.ruff.lint]
+select = ["E", "F"]
+"#,
+    )?;
+
+    // Create a subdirectory with its own pyproject.toml.
+    let subdir = project_dir.join("subdir");
+    std::fs::create_dir(&subdir)?;
+
+    std::fs::write(
+        subdir.join("pyproject.toml"),
+        r#"
+[tool.ruff]
+line-length = 120
+
+[tool.ruff.lint]
+select = ["E", "F", "I"]
+"#,
+    )?;
+
+    std::fs::write(subdir.join("test.py"), r#"import os"#).context("Failed to write test.py.")?;
+
+    insta::with_settings!({filters => vec![
+        (&*tempdir_filter(&project_dir), "<temp_dir>/"),
+        (r#"\\(\w\w|\s|\.|")"#, "/$1"),
+    ]}, {
+        assert_cmd_snapshot!(Command::new(get_cargo_bin(BIN_NAME))
+            .args(["check", "--show-settings", "subdir/test.py"])
+            .current_dir(&project_dir));
+    });
+
+    Ok(())
+}
+
 fn tempdir_filter(project_dir: &Path) -> String {
     format!(r#"{}\\?/?"#, regex::escape(project_dir.to_str().unwrap()))
 }

crates/ruff/tests/snapshots/show_settings__display_settings_from_nested_directory.snap

@@ -0,0 +1,410 @@
+---
+source: crates/ruff/tests/show_settings.rs
+info:
+  program: ruff
+  args:
+    - check
+    - "--show-settings"
+    - subdir/test.py
+---
+success: true
+exit_code: 0
+----- stdout -----
+Resolved settings for: "<temp_dir>/subdir/test.py"
+Settings path: "<temp_dir>/subdir/pyproject.toml"
+
+# General Settings
+cache_dir = "<temp_dir>/subdir/.ruff_cache"
+fix = false
+fix_only = false
+output_format = full
+show_fixes = false
+unsafe_fixes = hint
+
+# File Resolver Settings
+file_resolver.exclude = [
+	".bzr",
+	".direnv",
+	".eggs",
+	".git",
+	".git-rewrite",
+	".hg",
+	".ipynb_checkpoints",
+	".mypy_cache",
+	".nox",
+	".pants.d",
+	".pyenv",
+	".pytest_cache",
+	".pytype",
+	".ruff_cache",
+	".svn",
+	".tox",
+	".venv",
+	".vscode",
+	"__pypackages__",
+	"_build",
+	"buck-out",
+	"dist",
+	"node_modules",
+	"site-packages",
+	"venv",
+]
+file_resolver.extend_exclude = []
+file_resolver.force_exclude = false
+file_resolver.include = [
+	"*.py",
+	"*.pyi",
+	"*.ipynb",
+	"**/pyproject.toml",
+]
+file_resolver.extend_include = []
+file_resolver.respect_gitignore = true
+file_resolver.project_root = "<temp_dir>/subdir"
+
+# Linter Settings
+linter.exclude = []
+linter.project_root = "<temp_dir>/subdir"
+linter.rules.enabled = [
+	unsorted-imports (I001),
+	missing-required-import (I002),
+	mixed-spaces-and-tabs (E101),
+	multiple-imports-on-one-line (E401),
+	module-import-not-at-top-of-file (E402),
+	line-too-long (E501),
+	multiple-statements-on-one-line-colon (E701),
+	multiple-statements-on-one-line-semicolon (E702),
+	useless-semicolon (E703),
+	none-comparison (E711),
+	true-false-comparison (E712),
+	not-in-test (E713),
+	not-is-test (E714),
+	type-comparison (E721),
+	bare-except (E722),
+	lambda-assignment (E731),
+	ambiguous-variable-name (E741),
+	ambiguous-class-name (E742),
+	ambiguous-function-name (E743),
+	io-error (E902),
+	unused-import (F401),
+	import-shadowed-by-loop-var (F402),
+	undefined-local-with-import-star (F403),
+	late-future-import (F404),
+	undefined-local-with-import-star-usage (F405),
+	undefined-local-with-nested-import-star-usage (F406),
+	future-feature-not-defined (F407),
+	percent-format-invalid-format (F501),
+	percent-format-expected-mapping (F502),
+	percent-format-expected-sequence (F503),
+	percent-format-extra-named-arguments (F504),
+	percent-format-missing-argument (F505),
+	percent-format-mixed-positional-and-named (F506),
+	percent-format-positional-count-mismatch (F507),
+	percent-format-star-requires-sequence (F508),
+	percent-format-unsupported-format-character (F509),
+	string-dot-format-invalid-format (F521),
+	string-dot-format-extra-named-arguments (F522),
+	string-dot-format-extra-positional-arguments (F523),
+	string-dot-format-missing-arguments (F524),
+	string-dot-format-mixing-automatic (F525),
+	f-string-missing-placeholders (F541),
+	multi-value-repeated-key-literal (F601),
+	multi-value-repeated-key-variable (F602),
+	expressions-in-star-assignment (F621),
+	multiple-starred-expressions (F622),
+	assert-tuple (F631),
+	is-literal (F632),
+	invalid-print-syntax (F633),
+	if-tuple (F634),
+	break-outside-loop (F701),
+	continue-outside-loop (F702),
+	yield-outside-function (F704),
+	return-outside-function (F706),
+	default-except-not-last (F707),
+	forward-annotation-syntax-error (F722),
+	redefined-while-unused (F811),
+	undefined-name (F821),
+	undefined-export (F822),
+	undefined-local (F823),
+	unused-variable (F841),
+	unused-annotation (F842),
+	raise-not-implemented (F901),
+]
+linter.rules.should_fix = [
+	unsorted-imports (I001),
+	missing-required-import (I002),
+	mixed-spaces-and-tabs (E101),
+	multiple-imports-on-one-line (E401),
+	module-import-not-at-top-of-file (E402),
+	line-too-long (E501),
+	multiple-statements-on-one-line-colon (E701),
+	multiple-statements-on-one-line-semicolon (E702),
+	useless-semicolon (E703),
+	none-comparison (E711),
+	true-false-comparison (E712),
+	not-in-test (E713),
+	not-is-test (E714),
+	type-comparison (E721),
+	bare-except (E722),
+	lambda-assignment (E731),
+	ambiguous-variable-name (E741),
+	ambiguous-class-name (E742),
+	ambiguous-function-name (E743),
+	io-error (E902),
+	unused-import (F401),
+	import-shadowed-by-loop-var (F402),
+	undefined-local-with-import-star (F403),
+	late-future-import (F404),
+	undefined-local-with-import-star-usage (F405),
+	undefined-local-with-nested-import-star-usage (F406),
+	future-feature-not-defined (F407),
+	percent-format-invalid-format (F501),
+	percent-format-expected-mapping (F502),
+	percent-format-expected-sequence (F503),
+	percent-format-extra-named-arguments (F504),
+	percent-format-missing-argument (F505),
+	percent-format-mixed-positional-and-named (F506),
+	percent-format-positional-count-mismatch (F507),
+	percent-format-star-requires-sequence (F508),
+	percent-format-unsupported-format-character (F509),
+	string-dot-format-invalid-format (F521),
+	string-dot-format-extra-named-arguments (F522),
+	string-dot-format-extra-positional-arguments (F523),
+	string-dot-format-missing-arguments (F524),
+	string-dot-format-mixing-automatic (F525),
+	f-string-missing-placeholders (F541),
+	multi-value-repeated-key-literal (F601),
+	multi-value-repeated-key-variable (F602),
+	expressions-in-star-assignment (F621),
+	multiple-starred-expressions (F622),
+	assert-tuple (F631),
+	is-literal (F632),
+	invalid-print-syntax (F633),
+	if-tuple (F634),
+	break-outside-loop (F701),
+	continue-outside-loop (F702),
+	yield-outside-function (F704),
+	return-outside-function (F706),
+	default-except-not-last (F707),
+	forward-annotation-syntax-error (F722),
+	redefined-while-unused (F811),
+	undefined-name (F821),
+	undefined-export (F822),
+	undefined-local (F823),
+	unused-variable (F841),
+	unused-annotation (F842),
+	raise-not-implemented (F901),
+]
+linter.per_file_ignores = {}
+linter.safety_table.forced_safe = []
+linter.safety_table.forced_unsafe = []
+linter.unresolved_target_version = none
+linter.per_file_target_version = {}
+linter.preview = disabled
+linter.explicit_preview_rules = false
+linter.extension = ExtensionMapping({})
+linter.allowed_confusables = []
+linter.builtins = []
+linter.dummy_variable_rgx = ^(_+|(_+[a-zA-Z0-9_]*[a-zA-Z0-9]+?))$
+linter.external = []
+linter.ignore_init_module_imports = true
+linter.logger_objects = []
+linter.namespace_packages = []
+linter.src = [
+	"<temp_dir>/subdir",
+	"<temp_dir>/subdir/src",
+]
+linter.tab_size = 4
+linter.line_length = 120
+linter.task_tags = [
+	TODO,
+	FIXME,
+	XXX,
+]
+linter.typing_modules = []
+linter.typing_extensions = true
+
+# Linter Plugins
+linter.flake8_annotations.mypy_init_return = false
+linter.flake8_annotations.suppress_dummy_args = false
+linter.flake8_annotations.suppress_none_returning = false
+linter.flake8_annotations.allow_star_arg_any = false
+linter.flake8_annotations.ignore_fully_untyped = false
+linter.flake8_bandit.hardcoded_tmp_directory = [
+	/tmp,
+	/var/tmp,
+	/dev/shm,
+]
+linter.flake8_bandit.check_typed_exception = false
+linter.flake8_bandit.extend_markup_names = []
+linter.flake8_bandit.allowed_markup_calls = []
+linter.flake8_bugbear.extend_immutable_calls = []
+linter.flake8_builtins.allowed_modules = []
+linter.flake8_builtins.ignorelist = []
+linter.flake8_builtins.strict_checking = false
+linter.flake8_comprehensions.allow_dict_calls_with_keyword_arguments = false
+linter.flake8_copyright.notice_rgx = (?i)Copyright\s+((?:\(C\)|©)\s+)?\d{4}((-|,\s)\d{4})*
+linter.flake8_copyright.author = none
+linter.flake8_copyright.min_file_size = 0
+linter.flake8_errmsg.max_string_length = 0
+linter.flake8_gettext.function_names = [
+	_,
+	gettext,
+	ngettext,
+]
+linter.flake8_implicit_str_concat.allow_multiline = true
+linter.flake8_import_conventions.aliases = {
+	altair = alt,
+	holoviews = hv,
+	matplotlib = mpl,
+	matplotlib.pyplot = plt,
+	networkx = nx,
+	numpy = np,
+	numpy.typing = npt,
+	pandas = pd,
+	panel = pn,
+	plotly.express = px,
+	polars = pl,
+	pyarrow = pa,
+	seaborn = sns,
+	tensorflow = tf,
+	tkinter = tk,
+	xml.etree.ElementTree = ET,
+}
+linter.flake8_import_conventions.banned_aliases = {}
+linter.flake8_import_conventions.banned_from = []
+linter.flake8_pytest_style.fixture_parentheses = false
+linter.flake8_pytest_style.parametrize_names_type = tuple
+linter.flake8_pytest_style.parametrize_values_type = list
+linter.flake8_pytest_style.parametrize_values_row_type = tuple
+linter.flake8_pytest_style.raises_require_match_for = [
+	BaseException,
+	Exception,
+	ValueError,
+	OSError,
+	IOError,
+	EnvironmentError,
+	socket.error,
+]
+linter.flake8_pytest_style.raises_extend_require_match_for = []
+linter.flake8_pytest_style.mark_parentheses = false
+linter.flake8_quotes.inline_quotes = double
+linter.flake8_quotes.multiline_quotes = double
+linter.flake8_quotes.docstring_quotes = double
+linter.flake8_quotes.avoid_escape = true
+linter.flake8_self.ignore_names = [
+	_make,
+	_asdict,
+	_replace,
+	_fields,
+	_field_defaults,
+	_name_,
+	_value_,
+]
+linter.flake8_tidy_imports.ban_relative_imports = "parents"
+linter.flake8_tidy_imports.banned_api = {}
+linter.flake8_tidy_imports.banned_module_level_imports = []
+linter.flake8_type_checking.strict = false
+linter.flake8_type_checking.exempt_modules = [
+	typing,
+	typing_extensions,
+]
+linter.flake8_type_checking.runtime_required_base_classes = []
+linter.flake8_type_checking.runtime_required_decorators = []
+linter.flake8_type_checking.quote_annotations = false
+linter.flake8_unused_arguments.ignore_variadic_names = false
+linter.isort.required_imports = []
+linter.isort.combine_as_imports = false
+linter.isort.force_single_line = false
+linter.isort.force_sort_within_sections = false
+linter.isort.detect_same_package = true
+linter.isort.case_sensitive = false
+linter.isort.force_wrap_aliases = false
+linter.isort.force_to_top = []
+linter.isort.known_modules = {}
+linter.isort.order_by_type = true
+linter.isort.relative_imports_order = furthest_to_closest
+linter.isort.single_line_exclusions = []
+linter.isort.split_on_trailing_comma = true
+linter.isort.classes = []
+linter.isort.constants = []
+linter.isort.variables = []
+linter.isort.no_lines_before = []
+linter.isort.lines_after_imports = -1
+linter.isort.lines_between_types = 0
+linter.isort.forced_separate = []
+linter.isort.section_order = [
+	known { type = future },
+	known { type = standard_library },
+	known { type = third_party },
+	known { type = first_party },
+	known { type = local_folder },
+]
+linter.isort.default_section = known { type = third_party }
+linter.isort.no_sections = false
+linter.isort.from_first = false
+linter.isort.length_sort = false
+linter.isort.length_sort_straight = false
+linter.mccabe.max_complexity = 10
+linter.pep8_naming.ignore_names = [
+	setUp,
+	tearDown,
+	setUpClass,
+	tearDownClass,
+	setUpModule,
+	tearDownModule,
+	asyncSetUp,
+	asyncTearDown,
+	setUpTestData,
+	failureException,
+	longMessage,
+	maxDiff,
+]
+linter.pep8_naming.classmethod_decorators = []
+linter.pep8_naming.staticmethod_decorators = []
+linter.pycodestyle.max_line_length = 120
+linter.pycodestyle.max_doc_length = none
+linter.pycodestyle.ignore_overlong_task_comments = false
+linter.pyflakes.extend_generics = []
+linter.pyflakes.allowed_unused_imports = []
+linter.pylint.allow_magic_value_types = [
+	str,
+	bytes,
+]
+linter.pylint.allow_dunder_method_names = []
+linter.pylint.max_args = 5
+linter.pylint.max_positional_args = 5
+linter.pylint.max_returns = 6
+linter.pylint.max_bool_expr = 5
+linter.pylint.max_branches = 12
+linter.pylint.max_statements = 50
+linter.pylint.max_public_methods = 20
+linter.pylint.max_locals = 15
+linter.pylint.max_nested_blocks = 5
+linter.pyupgrade.keep_runtime_typing = false
+linter.ruff.parenthesize_tuple_in_subscript = false
+linter.ruff.strictly_empty_init_modules = false
+
+# Formatter Settings
+formatter.exclude = []
+formatter.unresolved_target_version = 3.10
+formatter.per_file_target_version = {}
+formatter.preview = disabled
+formatter.line_width = 120
+formatter.line_ending = auto
+formatter.indent_style = space
+formatter.indent_width = 4
+formatter.quote_style = double
+formatter.magic_trailing_comma = respect
+formatter.docstring_code_format = disabled
+formatter.docstring_code_line_width = dynamic
+
+# Analyze Settings
+analyze.exclude = []
+analyze.preview = disabled
+analyze.target_version = 3.10
+analyze.string_imports = disabled
+analyze.extension = ExtensionMapping({})
+analyze.include_dependencies = {}
+analyze.type_checking_imports = true
+
+----- stderr -----

crates/ruff_benchmark/benches/ty.rs

@@ -15,7 +15,7 @@ use ruff_db::files::{File, system_path_to_file};
 use ruff_db::source::source_text;
 use ruff_db::system::{InMemorySystem, MemoryFileSystem, SystemPath, SystemPathBuf, TestSystem};
 use ruff_python_ast::PythonVersion;
-use ty_project::metadata::options::{EnvironmentOptions, Options};
+use ty_project::metadata::options::{AnalysisOptions, EnvironmentOptions, Options};
 use ty_project::metadata::value::{RangedValue, RelativePathBuf};
 use ty_project::watch::{ChangeEvent, ChangedKind};
 use ty_project::{CheckMode, Db, ProjectDatabase, ProjectMetadata};
@@ -67,6 +67,7 @@ fn tomllib_path(file: &TestFile) -> SystemPathBuf {
     SystemPathBuf::from("src").join(file.name())
 }
 
+#[expect(clippy::needless_update)]
 fn setup_tomllib_case() -> Case {
     let system = TestSystem::default();
     let fs = system.memory_file_system().clone();
@@ -85,6 +86,10 @@ fn setup_tomllib_case() -> Case {
             python_version: Some(RangedValue::cli(PythonVersion::PY312)),
             ..EnvironmentOptions::default()
         }),
+        analysis: Some(AnalysisOptions {
+            respect_type_ignore_comments: Some(false),
+            ..AnalysisOptions::default()
+        }),
         ..Options::default()
     });
 
@@ -221,7 +226,7 @@ fn setup_micro_case(code: &str) -> Case {
     let file_path = "src/test.py";
     fs.write_file_all(
         SystemPathBuf::from(file_path),
-        ruff_python_trivia::textwrap::dedent(code),
+        &*ruff_python_trivia::textwrap::dedent(code),
     )
     .unwrap();
 
@@ -755,7 +760,7 @@ fn datetype(criterion: &mut Criterion) {
             max_dep_date: "2025-07-04",
             python_version: PythonVersion::PY313,
         },
-        2,
+        4,
     );
 
     bench_project(&benchmark, criterion);

crates/ruff_benchmark/benches/ty_walltime.rs

@@ -71,6 +71,8 @@ impl Display for Benchmark<'_> {
     }
 }
 
+#[track_caller]
+#[expect(clippy::cast_precision_loss)]
 fn check_project(db: &ProjectDatabase, project_name: &str, max_diagnostics: usize) {
     let result = db.check();
     let diagnostics = result.len();
@@ -79,6 +81,12 @@ fn check_project(db: &ProjectDatabase, project_name: &str, max_diagnostics: usiz
         diagnostics > 1 && diagnostics <= max_diagnostics,
         "Expected between 1 and {max_diagnostics} diagnostics on project '{project_name}' but got {diagnostics}",
     );
+
+    if (max_diagnostics - diagnostics) as f64 / max_diagnostics as f64 > 0.10 {
+        tracing::warn!(
+            "The expected diagnostics for project `{project_name}` can be reduced: expected {max_diagnostics} but got {diagnostics}"
+        );
+    }
 }
 
 static ALTAIR: Benchmark = Benchmark::new(
@@ -101,7 +109,7 @@ static ALTAIR: Benchmark = Benchmark::new(
         max_dep_date: "2025-06-17",
         python_version: PythonVersion::PY312,
     },
-    1000,
+    850,
 );
 
 static COLOUR_SCIENCE: Benchmark = Benchmark::new(
@@ -120,7 +128,7 @@ static COLOUR_SCIENCE: Benchmark = Benchmark::new(
         max_dep_date: "2025-06-17",
         python_version: PythonVersion::PY310,
     },
-    1070,
+    350,
 );
 
 static FREQTRADE: Benchmark = Benchmark::new(
@@ -163,7 +171,7 @@ static PANDAS: Benchmark = Benchmark::new(
         max_dep_date: "2025-06-17",
         python_version: PythonVersion::PY312,
     },
-    4000,
+    3800,
 );
 
 static PYDANTIC: Benchmark = Benchmark::new(
@@ -181,7 +189,7 @@ static PYDANTIC: Benchmark = Benchmark::new(
         max_dep_date: "2025-06-17",
         python_version: PythonVersion::PY39,
     },
-    7000,
+    3200,
 );
 
 static SYMPY: Benchmark = Benchmark::new(
@@ -194,7 +202,7 @@ static SYMPY: Benchmark = Benchmark::new(
         max_dep_date: "2025-06-17",
         python_version: PythonVersion::PY312,
     },
-    13116,
+    13400,
 );
 
 static TANJUN: Benchmark = Benchmark::new(
@@ -207,7 +215,7 @@ static TANJUN: Benchmark = Benchmark::new(
         max_dep_date: "2025-06-17",
         python_version: PythonVersion::PY312,
     },
-    320,
+    110,
 );
 
 static STATIC_FRAME: Benchmark = Benchmark::new(
@@ -223,7 +231,7 @@ static STATIC_FRAME: Benchmark = Benchmark::new(
         max_dep_date: "2025-08-09",
         python_version: PythonVersion::PY311,
     },
-    1100,
+    1700,
 );
 
 #[track_caller]

crates/ruff_db/src/cancellation.rs

@@ -1,3 +1,4 @@
+use std::fmt::Formatter;
 use std::sync::Arc;
 use std::sync::atomic::AtomicBool;
 
@@ -49,3 +50,15 @@ impl CancellationToken {
         self.cancelled.load(std::sync::atomic::Ordering::Relaxed)
     }
 }
+
+/// The operation was canceled by the provided [`CancellationToken`].
+#[derive(Debug)]
+pub struct Canceled;
+
+impl std::error::Error for Canceled {}
+
+impl std::fmt::Display for Canceled {
+    fn fmt(&self, f: &mut Formatter<'_>) -> std::fmt::Result {
+        f.write_str("operation was canceled")
+    }
+}

crates/ruff_db/src/diagnostic/mod.rs

@@ -98,6 +98,44 @@ impl Diagnostic {
         diag
     }
 
+    /// Adds sub diagnostics that tell the user that this is a bug in ty
+    /// and asks them to open an issue on GitHub.
+    pub fn add_bug_sub_diagnostics(&mut self, url_encoded_title: &str) {
+        self.sub(SubDiagnostic::new(
+            SubDiagnosticSeverity::Info,
+            "This indicates a bug in ty.",
+        ));
+
+        self.sub(SubDiagnostic::new(
+            SubDiagnosticSeverity::Info,
+            format_args!(
+                "If you could open an issue at https://github.com/astral-sh/ty/issues/new?title={url_encoded_title}, we'd be very appreciative!"
+            ),
+        ));
+        self.sub(SubDiagnostic::new(
+            SubDiagnosticSeverity::Info,
+            format!(
+                "Platform: {os} {arch}",
+                os = std::env::consts::OS,
+                arch = std::env::consts::ARCH
+            ),
+        ));
+        if let Some(version) = crate::program_version() {
+            self.sub(SubDiagnostic::new(
+                SubDiagnosticSeverity::Info,
+                format!("Version: {version}"),
+            ));
+        }
+
+        self.sub(SubDiagnostic::new(
+            SubDiagnosticSeverity::Info,
+            format!(
+                "Args: {args:?}",
+                args = std::env::args().collect::<Vec<_>>()
+            ),
+        ));
+    }
+
     /// Add an annotation to this diagnostic.
     ///
     /// Annotations for a diagnostic are optional, but if any are added,
@@ -1019,6 +1057,13 @@ impl DiagnosticId {
         matches!(self, DiagnosticId::Lint(_))
     }
 
+    pub const fn as_lint(&self) -> Option<LintName> {
+        match self {
+            DiagnosticId::Lint(name) => Some(*name),
+            _ => None,
+        }
+    }
+
     /// Returns `true` if this `DiagnosticId` represents a lint with the given name.
     pub fn is_lint_named(&self, name: &str) -> bool {
         matches!(self, DiagnosticId::Lint(self_name) if self_name == name)

crates/ruff_db/src/files.rs

@@ -14,6 +14,7 @@ use crate::diagnostic::{Span, UnifiedFile};
 use crate::file_revision::FileRevision;
 use crate::files::file_root::FileRoots;
 use crate::files::private::FileStatus;
+use crate::source::SourceText;
 use crate::system::{SystemPath, SystemPathBuf, SystemVirtualPath, SystemVirtualPathBuf};
 use crate::vendored::{VendoredPath, VendoredPathBuf};
 use crate::{Db, FxDashMap, vendored};
@@ -323,6 +324,17 @@ pub struct File {
     /// the file has been deleted is to change the status to `Deleted`.
     #[default]
     status: FileStatus,
+
+    /// Overrides the result of [`source_text`](crate::source::source_text).
+    ///
+    /// This is useful when running queries after modifying a file's content but
+    /// before the content is written to disk. For example, to verify that the applied fixes
+    /// didn't introduce any new errors.
+    ///
+    /// The override gets automatically removed the next time the file changes.
+    #[default]
+    #[returns(ref)]
+    pub source_text_override: Option<SourceText>,
 }
 
 // The Salsa heap is tracked separately.
@@ -444,20 +456,28 @@ impl File {
             _ => (FileStatus::NotFound, FileRevision::zero(), None),
         };
 
+        let mut clear_override = false;
+
         if file.status(db) != status {
             tracing::debug!("Updating the status of `{}`", file.path(db));
             file.set_status(db).to(status);
+            clear_override = true;
         }
 
         if file.revision(db) != revision {
             tracing::debug!("Updating the revision of `{}`", file.path(db));
             file.set_revision(db).to(revision);
+            clear_override = true;
         }
 
         if file.permissions(db) != permission {
             tracing::debug!("Updating the permissions of `{}`", file.path(db));
             file.set_permissions(db).to(permission);
         }
+
+        if clear_override && file.source_text_override(db).is_some() {
+            file.set_source_text_override(db).to(None);
+        }
     }
 
     /// Returns `true` if the file exists.
@@ -526,7 +546,7 @@ impl VirtualFile {
     }
 
     /// Increments the revision of the underlying [`File`].
-    fn sync(&self, db: &mut dyn Db) {
+    pub fn sync(&self, db: &mut dyn Db) {
         let file = self.0;
         tracing::debug!("Updating the revision of `{}`", file.path(db));
         let current_revision = file.revision(db);

crates/ruff_db/src/lib.rs

@@ -85,6 +85,13 @@ pub fn max_parallelism() -> NonZeroUsize {
         })
 }
 
+// Use a reasonably large stack size to avoid running into stack overflows too easily. The
+// size was chosen in such a way as to still be able to handle large expressions involving
+// binary operators (x + x + … + x) both during the AST walk in semantic index building as
+// well as during type checking. Using this stack size, we can handle handle expressions
+// that are several times larger than the corresponding limits in existing type checkers.
+pub const STACK_SIZE: usize = 16 * 1024 * 1024;
+
 /// Trait for types that can provide Rust documentation.
 ///
 /// Use `derive(RustDoc)` to automatically implement this trait for types that have a static string documentation.

crates/ruff_db/src/source.rs

@@ -1,6 +1,8 @@
+use std::borrow::Cow;
 use std::ops::Deref;
 use std::sync::Arc;
 
+use ruff_diagnostics::SourceMap;
 use ruff_notebook::Notebook;
 use ruff_python_ast::PySourceType;
 use ruff_source_file::LineIndex;
@@ -16,6 +18,10 @@ pub fn source_text(db: &dyn Db, file: File) -> SourceText {
     let _span = tracing::trace_span!("source_text", file = %path).entered();
     let mut read_error = None;
 
+    if let Some(source) = file.source_text_override(db) {
+        return source.clone();
+    }
+
     let kind = if is_notebook(db.system(), path) {
         file.read_to_notebook(db)
             .unwrap_or_else(|error| {
@@ -90,6 +96,45 @@ impl SourceText {
     pub fn read_error(&self) -> Option<&SourceTextError> {
         self.inner.read_error.as_ref()
     }
+
+    /// Returns a new instance for this file with the updated source text (Python code).
+    ///
+    /// Uses the `source_map` to preserve the cell-boundaries.
+    #[must_use]
+    pub fn with_text(&self, new_text: String, source_map: &SourceMap) -> Self {
+        let new_kind = match &self.inner.kind {
+            SourceTextKind::Text(_) => SourceTextKind::Text(new_text),
+
+            SourceTextKind::Notebook { notebook } => {
+                let mut new_notebook = notebook.as_ref().clone();
+                new_notebook.update(source_map, new_text);
+                SourceTextKind::Notebook {
+                    notebook: new_notebook.into(),
+                }
+            }
+        };
+
+        Self {
+            inner: Arc::new(SourceTextInner {
+                kind: new_kind,
+                read_error: self.inner.read_error.clone(),
+            }),
+        }
+    }
+
+    pub fn to_bytes(&self) -> Cow<'_, [u8]> {
+        match &self.inner.kind {
+            SourceTextKind::Text(source) => Cow::Borrowed(source.as_bytes()),
+            SourceTextKind::Notebook { notebook } => {
+                let mut output: Vec<u8> = Vec::new();
+                notebook
+                    .write(&mut output)
+                    .expect("writing to a Vec should never fail");
+
+                Cow::Owned(output)
+            }
+        }
+    }
 }
 
 impl Deref for SourceText {
@@ -117,13 +162,13 @@ impl std::fmt::Debug for SourceText {
     }
 }
 
-#[derive(Eq, PartialEq, get_size2::GetSize)]
+#[derive(Eq, PartialEq, get_size2::GetSize, Clone)]
 struct SourceTextInner {
     kind: SourceTextKind,
     read_error: Option<SourceTextError>,
 }
 
-#[derive(Eq, PartialEq, get_size2::GetSize)]
+#[derive(Eq, PartialEq, get_size2::GetSize, Clone)]
 enum SourceTextKind {
     Text(String),
     Notebook {

crates/ruff_db/src/system.rs

@@ -271,7 +271,12 @@ pub trait WritableSystem: System {
     fn create_new_file(&self, path: &SystemPath) -> Result<()>;
 
     /// Writes the given content to the file at the given path.
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()>;
+    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
+        self.write_file_bytes(path, content.as_bytes())
+    }
+
+    /// Writes the given content to the file at the given path.
+    fn write_file_bytes(&self, path: &SystemPath, content: &[u8]) -> Result<()>;
 
     /// Creates a directory at `path` as well as any intermediate directories.
     fn create_directory_all(&self, path: &SystemPath) -> Result<()>;
@@ -311,6 +316,8 @@ pub trait WritableSystem: System {
 
         Ok(Some(cache_path))
     }
+
+    fn dyn_clone(&self) -> Box<dyn WritableSystem>;
 }
 
 #[derive(Clone, Debug, Eq, PartialEq)]

crates/ruff_db/src/system/memory_fs.rs

@@ -122,7 +122,9 @@ impl MemoryFileSystem {
             let entry = by_path.get(&normalized).ok_or_else(not_found)?;
 
             match entry {
-                Entry::File(file) => Ok(file.content.clone()),
+                Entry::File(file) => {
+                    String::from_utf8(file.content.to_vec()).map_err(|_| invalid_utf8())
+                }
                 Entry::Directory(_) => Err(is_a_directory()),
             }
         }
@@ -139,7 +141,7 @@ impl MemoryFileSystem {
             .get(&path.as_ref().to_path_buf())
             .ok_or_else(not_found)?;
 
-        Ok(file.content.clone())
+        String::from_utf8(file.content.to_vec()).map_err(|_| invalid_utf8())
     }
 
     pub fn exists(&self, path: &SystemPath) -> bool {
@@ -161,7 +163,7 @@ impl MemoryFileSystem {
         match by_path.entry(normalized) {
             btree_map::Entry::Vacant(entry) => {
                 entry.insert(Entry::File(File {
-                    content: String::new(),
+                    content: Box::default(),
                     last_modified: file_time_now(),
                 }));
 
@@ -177,13 +179,17 @@ impl MemoryFileSystem {
     /// Stores a new file in the file system.
     ///
     /// The operation overrides the content for an existing file with the same normalized `path`.
-    pub fn write_file(&self, path: impl AsRef<SystemPath>, content: impl ToString) -> Result<()> {
+    pub fn write_file(
+        &self,
+        path: impl AsRef<SystemPath>,
+        content: impl AsRef<[u8]>,
+    ) -> Result<()> {
         let mut by_path = self.inner.by_path.write().unwrap();
 
         let normalized = self.normalize_path(path.as_ref());
 
         let file = get_or_create_file(&mut by_path, &normalized)?;
-        file.content = content.to_string();
+        file.content = content.as_ref().to_vec().into_boxed_slice();
         file.last_modified = file_time_now();
 
         Ok(())
@@ -214,7 +220,7 @@ impl MemoryFileSystem {
     pub fn write_file_all(
         &self,
         path: impl AsRef<SystemPath>,
-        content: impl ToString,
+        content: impl AsRef<[u8]>,
     ) -> Result<()> {
         let path = path.as_ref();
 
@@ -228,19 +234,24 @@ impl MemoryFileSystem {
     /// Stores a new virtual file in the file system.
     ///
     /// The operation overrides the content for an existing virtual file with the same `path`.
-    pub fn write_virtual_file(&self, path: impl AsRef<SystemVirtualPath>, content: impl ToString) {
+    pub fn write_virtual_file(
+        &self,
+        path: impl AsRef<SystemVirtualPath>,
+        content: impl AsRef<[u8]>,
+    ) {
         let path = path.as_ref();
         let mut virtual_files = self.inner.virtual_files.write().unwrap();
+        let content = content.as_ref().to_vec().into_boxed_slice();
 
         match virtual_files.entry(path.to_path_buf()) {
             std::collections::hash_map::Entry::Vacant(entry) => {
                 entry.insert(File {
-                    content: content.to_string(),
+                    content,
                     last_modified: file_time_now(),
                 });
             }
             std::collections::hash_map::Entry::Occupied(mut entry) => {
-                entry.get_mut().content = content.to_string();
+                entry.get_mut().content = content;
             }
         }
     }
@@ -468,7 +479,7 @@ impl Entry {
 
 #[derive(Debug)]
 struct File {
-    content: String,
+    content: Box<[u8]>,
     last_modified: FileTime,
 }
 
@@ -497,6 +508,13 @@ fn directory_not_empty() -> std::io::Error {
     std::io::Error::other("directory not empty")
 }
 
+fn invalid_utf8() -> std::io::Error {
+    std::io::Error::new(
+        std::io::ErrorKind::InvalidData,
+        "stream did not contain valid UTF-8",
+    )
+}
+
 fn create_dir_all(
     paths: &mut RwLockWriteGuard<BTreeMap<Utf8PathBuf, Entry>>,
     normalized: &Utf8Path,
@@ -533,7 +551,7 @@ fn get_or_create_file<'a>(
 
     let entry = paths.entry(normalized.to_path_buf()).or_insert_with(|| {
         Entry::File(File {
-            content: String::new(),
+            content: Box::default(),
             last_modified: file_time_now(),
         })
     });
@@ -844,7 +862,7 @@ mod tests {
         let fs = with_files(["c.py"]);
 
         let error = fs
-            .write_file(SystemPath::new("a/b.py"), "content".to_string())
+            .write_file(SystemPath::new("a/b.py"), "content")
             .unwrap_err();
 
         assert_eq!(error.kind(), ErrorKind::NotFound);
@@ -855,7 +873,7 @@ mod tests {
         let fs = with_files(["a/b.py"]);
 
         let error = fs
-            .write_file_all(SystemPath::new("a/b.py/c"), "content".to_string())
+            .write_file_all(SystemPath::new("a/b.py/c"), "content")
             .unwrap_err();
 
         assert_eq!(error.kind(), ErrorKind::Other);
@@ -878,7 +896,7 @@ mod tests {
         let fs = MemoryFileSystem::new();
         let path = SystemPath::new("a.py");
 
-        fs.write_file_all(path, "Test content".to_string())?;
+        fs.write_file_all(path, "Test content")?;
 
         assert_eq!(fs.read_to_string(path)?, "Test content");
 
@@ -915,9 +933,7 @@ mod tests {
 
         fs.create_directory_all("a")?;
 
-        let error = fs
-            .write_file(SystemPath::new("a"), "content".to_string())
-            .unwrap_err();
+        let error = fs.write_file(SystemPath::new("a"), "content").unwrap_err();
 
         assert_eq!(error.kind(), ErrorKind::Other);
 

crates/ruff_db/src/system/os.rs

@@ -361,13 +361,17 @@ impl WritableSystem for OsSystem {
         std::fs::File::create_new(path).map(drop)
     }
 
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
+    fn write_file_bytes(&self, path: &SystemPath, content: &[u8]) -> Result<()> {
         std::fs::write(path.as_std_path(), content)
     }
 
     fn create_directory_all(&self, path: &SystemPath) -> Result<()> {
         std::fs::create_dir_all(path.as_std_path())
     }
+
+    fn dyn_clone(&self) -> Box<dyn WritableSystem> {
+        Box::new(self.clone())
+    }
 }
 
 impl Default for OsSystem {

crates/ruff_db/src/system/test.rs

@@ -205,13 +205,17 @@ impl WritableSystem for TestSystem {
         self.system().create_new_file(path)
     }
 
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
-        self.system().write_file(path, content)
+    fn write_file_bytes(&self, path: &SystemPath, content: &[u8]) -> Result<()> {
+        self.system().write_file_bytes(path, content)
     }
 
     fn create_directory_all(&self, path: &SystemPath) -> Result<()> {
         self.system().create_directory_all(path)
     }
+
+    fn dyn_clone(&self) -> Box<dyn WritableSystem> {
+        Box::new(self.clone())
+    }
 }
 
 /// Extension trait for databases that use a [`WritableSystem`].
@@ -283,7 +287,11 @@ pub trait DbWithTestSystem: Db + Sized {
     ///
     /// ## Panics
     /// If the db isn't using the [`InMemorySystem`].
-    fn write_virtual_file(&mut self, path: impl AsRef<SystemVirtualPath>, content: impl ToString) {
+    fn write_virtual_file(
+        &mut self,
+        path: impl AsRef<SystemVirtualPath>,
+        content: impl AsRef<[u8]>,
+    ) {
         let path = path.as_ref();
         self.test_system()
             .memory_file_system()
@@ -322,23 +330,23 @@ where
     }
 }
 
-#[derive(Default, Debug)]
+#[derive(Clone, Default, Debug)]
 pub struct InMemorySystem {
-    user_config_directory: Mutex<Option<SystemPathBuf>>,
+    user_config_directory: Arc<Mutex<Option<SystemPathBuf>>>,
     memory_fs: MemoryFileSystem,
 }
 
 impl InMemorySystem {
     pub fn new(cwd: SystemPathBuf) -> Self {
         Self {
-            user_config_directory: Mutex::new(None),
+            user_config_directory: Mutex::new(None).into(),
             memory_fs: MemoryFileSystem::with_current_directory(cwd),
         }
     }
 
     pub fn from_memory_fs(memory_fs: MemoryFileSystem) -> Self {
         Self {
-            user_config_directory: Mutex::new(None),
+            user_config_directory: Mutex::new(None).into(),
             memory_fs,
         }
     }
@@ -440,10 +448,7 @@ impl System for InMemorySystem {
     }
 
     fn dyn_clone(&self) -> Box<dyn System> {
-        Box::new(Self {
-            user_config_directory: Mutex::new(self.user_config_directory.lock().unwrap().clone()),
-            memory_fs: self.memory_fs.clone(),
-        })
+        Box::new(self.clone())
     }
 }
 
@@ -452,11 +457,15 @@ impl WritableSystem for InMemorySystem {
         self.memory_fs.create_new_file(path)
     }
 
-    fn write_file(&self, path: &SystemPath, content: &str) -> Result<()> {
+    fn write_file_bytes(&self, path: &SystemPath, content: &[u8]) -> Result<()> {
         self.memory_fs.write_file(path, content)
     }
 
     fn create_directory_all(&self, path: &SystemPath) -> Result<()> {
         self.memory_fs.create_directory_all(path)
     }
+
+    fn dyn_clone(&self) -> Box<dyn WritableSystem> {
+        Box::new(self.clone())
+    }
 }

crates/ruff_formatter/shared_traits.rs

@@ -13,7 +13,10 @@ impl<T, C> AsFormat<C> for &T
 where
     T: AsFormat<C>,
 {
-    type Format<'a> = T::Format<'a> where Self: 'a;
+    type Format<'a>
+        = T::Format<'a>
+    where
+        Self: 'a;
 
     fn format(&self) -> Self::Format<'_> {
         AsFormat::format(&**self)

crates/ruff_linter/Cargo.toml

@@ -1,6 +1,6 @@
 [package]
 name = "ruff_linter"
-version = "0.14.10"
+version = "0.14.11"
 publish = false
 authors = { workspace = true }
 edition = { workspace = true }

crates/ruff_linter/src/linter.rs

@@ -26,6 +26,7 @@ use crate::doc_lines::{doc_lines_from_ast, doc_lines_from_tokens};
 use crate::fix::{FixResult, fix_file};
 use crate::noqa::add_noqa;
 use crate::package::PackageRoot;
+use crate::preview::is_py315_support_enabled;
 use crate::registry::Rule;
 #[cfg(any(feature = "test-rules", test))]
 use crate::rules::ruff::rules::test_rules::{self, TEST_RULES, TestRule};
@@ -33,7 +34,7 @@ use crate::settings::types::UnsafeFixes;
 use crate::settings::{LinterSettings, TargetVersion, flags};
 use crate::source_kind::SourceKind;
 use crate::suppression::Suppressions;
-use crate::{Locator, directives, fs};
+use crate::{Locator, directives, fs, warn_user_once};
 
 pub(crate) mod float;
 
@@ -450,6 +451,14 @@ pub fn lint_only(
 ) -> LinterResult {
     let target_version = settings.resolve_target_version(path);
 
+    if matches!(target_version.linter_version(), PythonVersion::PY315)
+        && !is_py315_support_enabled(settings)
+    {
+        warn_user_once!(
+            "Support for Python 3.15 is under development and may be unstable. Enable `preview` to remove this warning."
+        );
+    }
+
     let parsed = source.into_parsed(source_kind, source_type, target_version.parser_version());
 
     // Map row and column locations to byte slices (lazily).
@@ -555,6 +564,14 @@ pub fn lint_fix<'a>(
 
     let target_version = settings.resolve_target_version(path);
 
+    if matches!(target_version.linter_version(), PythonVersion::PY315)
+        && !is_py315_support_enabled(settings)
+    {
+        warn_user_once!(
+            "Support for Python 3.15 is under development and may be unstable. Enable `preview` to remove this warning."
+        );
+    }
+
     // Continuously fix until the source code stabilizes.
     loop {
         // Parse once.

crates/ruff_linter/src/preview.rs

@@ -296,3 +296,8 @@ pub(crate) const fn is_s310_resolve_string_literal_bindings_enabled(
 pub(crate) const fn is_range_suppressions_enabled(settings: &LinterSettings) -> bool {
     settings.preview.is_enabled()
 }
+
+// https://github.com/astral-sh/ruff/pull/22419
+pub(crate) const fn is_py315_support_enabled(settings: &LinterSettings) -> bool {
+    settings.preview.is_enabled()
+}

crates/ruff_linter/src/rules/flake8_print/rules/print_call.rs

@@ -36,13 +36,16 @@ use crate::{Fix, FixAvailability, Violation};
 /// ```python
 /// import logging
 ///
-/// logging.basicConfig(level=logging.INFO)
 /// logger = logging.getLogger(__name__)
 ///
 ///
 /// def sum_less_than_four(a, b):
 ///     logger.debug("Calling sum_less_than_four")
 ///     return a + b < 4
+///
+///
+/// if __name__ == "__main__":
+///     logging.basicConfig(level=logging.INFO)
 /// ```
 ///
 /// ## Fix safety

crates/ruff_linter/src/rules/flake8_pytest_style/rules/assertion.rs

@@ -106,6 +106,16 @@ impl Violation for PytestCompositeAssertion {
 ///     assert exc_info.value.args
 /// ```
 ///
+/// Or, for pytest 8.4.0 and later:
+/// ```python
+/// import pytest
+///
+///
+/// def test_foo():
+///     with pytest.raises(ZeroDivisionError, check=lambda e: e.args):
+///         1 / 0
+/// ```
+///
 /// ## References
 /// - [`pytest` documentation: `pytest.raises`](https://docs.pytest.org/en/latest/reference/reference.html#pytest-raises)
 #[derive(ViolationMetadata)]

crates/ruff_linter/src/rules/flake8_self/rules/private_member_access.rs

@@ -101,7 +101,7 @@ pub(crate) fn private_member_access(checker: &Checker, expr: &Expr) {
         }
     }
 
-    // Allow some documented private methods, like `os._exit()`.
+    // Allow some public functions whose names start with an underscore, like `os._exit()`.
     if let Some(qualified_name) = semantic.resolve_qualified_name(expr) {
         if matches!(qualified_name.segments(), ["os", "_exit"]) {
             return;

crates/ruff_linter/src/rules/isort/rules/add_required_imports.rs

@@ -140,7 +140,7 @@ pub(crate) fn add_required_imports(
     source_type: PySourceType,
     context: &LintContext,
 ) {
-    for required_import in &settings.isort.required_imports {
+    for required_import in settings.isort.required_imports.iter().rev() {
         add_required_import(
             required_import,
             parsed,

crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__required_imports_docstring.py.snap

@@ -1,14 +1,6 @@
 ---
 source: crates/ruff_linter/src/rules/isort/mod.rs
 ---
-I002 [*] Missing required import: `from __future__ import annotations`
---> docstring.py:1:1
-help: Insert required import: `from __future__ import annotations`
-1 | """Hello, world!"""
-2 + from __future__ import annotations
-3 | 
-4 | x = 1
-
 I002 [*] Missing required import: `from __future__ import generator_stop`
 --> docstring.py:1:1
 help: Insert required import: `from __future__ import generator_stop`
@@ -16,3 +8,11 @@ help: Insert required import: `from __future__ import generator_stop`
 2 + from __future__ import generator_stop
 3 | 
 4 | x = 1
+
+I002 [*] Missing required import: `from __future__ import annotations`
+--> docstring.py:1:1
+help: Insert required import: `from __future__ import annotations`
+1 | """Hello, world!"""
+2 + from __future__ import annotations
+3 | 
+4 | x = 1

crates/ruff_linter/src/rules/isort/snapshots/ruff_linter__rules__isort__tests__required_imports_multiple_strings.py.snap

@@ -1,15 +1,6 @@
 ---
 source: crates/ruff_linter/src/rules/isort/mod.rs
 ---
-I002 [*] Missing required import: `from __future__ import annotations`
---> multiple_strings.py:1:1
-help: Insert required import: `from __future__ import annotations`
-1 | """This is a docstring."""
-2 + from __future__ import annotations
-3 | "This is not a docstring."
-4 | "This is also not a docstring."
-5 | 
-
 I002 [*] Missing required import: `from __future__ import generator_stop`
 --> multiple_strings.py:1:1
 help: Insert required import: `from __future__ import generator_stop`
@@ -17,4 +8,13 @@ help: Insert required import: `from __future__ import generator_stop`
 2 + from __future__ import generator_stop
 3 | "This is not a docstring."
 4 | "This is also not a docstring."
+5 | 
+
+I002 [*] Missing required import: `from __future__ import annotations`
+--> multiple_strings.py:1:1
+help: Insert required import: `from __future__ import annotations`
+1 | """This is a docstring."""
+2 + from __future__ import annotations
+3 | "This is not a docstring."
+4 | "This is also not a docstring."
 5 |

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

@@ -5,7 +5,7 @@ use ruff_text_size::Ranged;
 
 use crate::checkers::ast::Checker;
 use crate::fix::edits::add_argument;
-use crate::{AlwaysFixableViolation, Applicability, Fix};
+use crate::{Fix, FixAvailability, Violation};
 
 /// ## What it does
 /// Checks for uses of `subprocess.run` without an explicit `check` argument.
@@ -39,9 +39,12 @@ use crate::{AlwaysFixableViolation, Applicability, Fix};
 /// ```
 ///
 /// ## Fix safety
-/// This rule's fix is marked as unsafe for function calls that contain
-/// `**kwargs`, as adding a `check` keyword argument to such a call may lead
-/// to a duplicate keyword argument error.
+///
+/// This rule's fix is marked as display-only because it's not clear whether the
+/// potential exception was meant to be ignored by setting `check=False` or if
+/// the author simply forgot to include `check=True`. The fix adds
+/// `check=False`, making the existing behavior explicit but possibly masking
+/// the original intention.
 ///
 /// ## References
 /// - [Python documentation: `subprocess.run`](https://docs.python.org/3/library/subprocess.html#subprocess.run)
@@ -49,14 +52,18 @@ use crate::{AlwaysFixableViolation, Applicability, Fix};
 #[violation_metadata(stable_since = "v0.0.285")]
 pub(crate) struct SubprocessRunWithoutCheck;
 
-impl AlwaysFixableViolation for SubprocessRunWithoutCheck {
+impl Violation for SubprocessRunWithoutCheck {
+    // The fix is always set on the diagnostic, but display-only fixes aren't
+    // considered "fixable" in the tests.
+    const FIX_AVAILABILITY: FixAvailability = FixAvailability::Sometimes;
+
     #[derive_message_formats]
     fn message(&self) -> String {
         "`subprocess.run` without explicit `check` argument".to_string()
     }
 
-    fn fix_title(&self) -> String {
-        "Add explicit `check=False`".to_string()
+    fn fix_title(&self) -> Option<String> {
+        Some("Add explicit `check=False`".to_string())
     }
 }
 
@@ -74,20 +81,11 @@ pub(crate) fn subprocess_run_without_check(checker: &Checker, call: &ast::ExprCa
         if call.arguments.find_keyword("check").is_none() {
             let mut diagnostic =
                 checker.report_diagnostic(SubprocessRunWithoutCheck, call.func.range());
-            diagnostic.set_fix(Fix::applicable_edit(
-                add_argument("check=False", &call.arguments, checker.tokens()),
-                // If the function call contains `**kwargs`, mark the fix as unsafe.
-                if call
-                    .arguments
-                    .keywords
-                    .iter()
-                    .any(|keyword| keyword.arg.is_none())
-                {
-                    Applicability::Unsafe
-                } else {
-                    Applicability::Safe
-                },
-            ));
+            diagnostic.set_fix(Fix::display_only_edit(add_argument(
+                "check=False",
+                &call.arguments,
+                checker.tokens(),
+            )));
         }
     }
 }

crates/ruff_linter/src/rules/pylint/snapshots/ruff_linter__rules__pylint__tests__PLW1510_subprocess_run_without_check.py.snap

@@ -19,6 +19,7 @@ help: Add explicit `check=False`
 5 | subprocess.run("ls", shell=True)
 6 | subprocess.run(
 7 |     ["ls"],
+note: This is a display-only fix and is likely to be incorrect
 
 PLW1510 [*] `subprocess.run` without explicit `check` argument
  --> subprocess_run_without_check.py:5:1
@@ -39,6 +40,7 @@ help: Add explicit `check=False`
 6 | subprocess.run(
 7 |     ["ls"],
 8 |     shell=False,
+note: This is a display-only fix and is likely to be incorrect
 
 PLW1510 [*] `subprocess.run` without explicit `check` argument
  --> subprocess_run_without_check.py:6:1
@@ -59,6 +61,7 @@ help: Add explicit `check=False`
 9  | )
 10 | subprocess.run(["ls"], **kwargs)
 11 | 
+note: This is a display-only fix and is likely to be incorrect
 
 PLW1510 [*] `subprocess.run` without explicit `check` argument
   --> subprocess_run_without_check.py:10:1
@@ -79,4 +82,4 @@ help: Add explicit `check=False`
 11 | 
 12 | # Non-errors.
 13 | subprocess.run("ls", check=True)
-note: This is an unsafe fix and may change runtime behavior
+note: This is a display-only fix and is likely to be incorrect

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

@@ -398,17 +398,17 @@ mod tests {
         1 + from pipes import Template
         2 + from shlex import quote
 
-        I002 [*] Missing required import: `from __future__ import generator_stop`
-        --> <filename>:1:1
-        help: Insert required import: `from __future__ import generator_stop`
-        1 + from __future__ import generator_stop
-        2 | from pipes import quote, Template
-
         I002 [*] Missing required import: `from collections import Sequence`
         --> <filename>:1:1
         help: Insert required import: `from collections import Sequence`
         1 + from collections import Sequence
         2 | from pipes import quote, Template
+
+        I002 [*] Missing required import: `from __future__ import generator_stop`
+        --> <filename>:1:1
+        help: Insert required import: `from __future__ import generator_stop`
+        1 + from __future__ import generator_stop
+        2 | from pipes import quote, Template
         ");
     }
 

crates/ruff_linter/src/rules/ruff/rules/invalid_rule_code.rs

@@ -52,6 +52,7 @@ impl InvalidRuleCodeKind {
 pub(crate) struct InvalidRuleCode {
     pub(crate) rule_code: String,
     pub(crate) kind: InvalidRuleCodeKind,
+    pub(crate) whole_comment: bool,
 }
 
 impl AlwaysFixableViolation for InvalidRuleCode {
@@ -65,7 +66,11 @@ impl AlwaysFixableViolation for InvalidRuleCode {
     }
 
     fn fix_title(&self) -> String {
-        "Remove the rule code".to_string()
+        if self.whole_comment {
+            format!("Remove the {} comment", self.kind.as_str())
+        } else {
+            format!("Remove the rule code `{}`", self.rule_code)
+        }
     }
 }
 
@@ -122,6 +127,7 @@ fn all_codes_invalid_diagnostic(
                     .collect::<Vec<_>>()
                     .join(", "),
                 kind: InvalidRuleCodeKind::Noqa,
+                whole_comment: true,
             },
             directive.range(),
         )
@@ -139,6 +145,7 @@ fn some_codes_are_invalid_diagnostic(
             InvalidRuleCode {
                 rule_code: invalid_code.to_string(),
                 kind: InvalidRuleCodeKind::Noqa,
+                whole_comment: false,
             },
             invalid_code.range(),
         )

crates/ruff_linter/src/rules/ruff/rules/invalid_suppression_comment.rs

@@ -12,7 +12,7 @@ use crate::suppression::{InvalidSuppressionKind, ParseErrorKind};
 ///
 /// ## Example
 /// ```python
-/// ruff: disable  # missing codes
+/// # ruff: disable  # missing codes
 /// ```
 ///
 /// Use instead:

crates/ruff_linter/src/rules/ruff/rules/unused_noqa.rs

@@ -52,6 +52,25 @@ impl UnusedNOQAKind {
 ///     foo.bar()
 /// ```
 ///
+/// ## Conflict with other linters
+/// When using `RUF100` with the `--fix` option, Ruff may remove trailing comments
+/// that follow a `# noqa` directive on the same line, as it interprets the
+/// remainder of the line as a description for the suppression.
+///
+/// To prevent Ruff from removing suppressions for other tools (like `pylint`
+/// or `mypy`), separate them with a second `#` character:
+///
+/// ```python
+/// # Bad: Ruff --fix will remove the pylint comment
+/// def visit_ImportFrom(self, node):  # noqa: N802, pylint: disable=invalid-name
+///     pass
+///
+///
+/// # Good: Ruff will preserve the pylint comment
+/// def visit_ImportFrom(self, node):  # noqa: N802 # pylint: disable=invalid-name
+///     pass
+/// ```
+///
 /// ## Options
 /// - `lint.external`
 ///

crates/ruff_linter/src/rules/ruff/snapshots/ruff_linter__rules__ruff__tests__RUF102_RUF102.py.snap

@@ -10,7 +10,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID123
 3 | # External code
 4 | import re  # noqa: V123
   |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 1 | # Invalid code
   - import os  # noqa: INVALID123
 2 + import os  
@@ -28,7 +28,7 @@ RUF102 [*] Invalid rule code in `# noqa`: V123
 5 | # Valid noqa
 6 | import sys  # noqa: E402
   |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 1 | # Invalid code
 2 | import os  # noqa: INVALID123
 3 | # External code
@@ -48,7 +48,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID456
 8 | from itertools import product  # Preceeding comment # noqa: INVALID789
 9 | # Succeeding comment
   |
-help: Remove the rule code
+help: Remove the rule code `INVALID456`
 4  | import re  # noqa: V123
 5  | # Valid noqa
 6  | import sys  # noqa: E402
@@ -68,7 +68,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID789
  9 | # Succeeding comment
 10 | import math # noqa: INVALID000 # Succeeding comment
    |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 5  | # Valid noqa
 6  | import sys  # noqa: E402
 7  | from functools import cache  # Preceeding comment # noqa: F401, INVALID456
@@ -88,7 +88,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID000
 11 | # Mixed valid and invalid
 12 | from typing import List  # noqa: F401, INVALID123
    |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 7  | from functools import cache  # Preceeding comment # noqa: F401, INVALID456
 8  | from itertools import product  # Preceeding comment # noqa: INVALID789
 9  | # Succeeding comment
@@ -108,7 +108,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID123
 13 | # Test for multiple invalid
 14 | from collections import defaultdict  # noqa: INVALID100, INVALID200, F401
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID123`
 9  | # Succeeding comment
 10 | import math # noqa: INVALID000 # Succeeding comment
 11 | # Mixed valid and invalid
@@ -128,7 +128,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID100
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID100`
 11 | # Mixed valid and invalid
 12 | from typing import List  # noqa: F401, INVALID123
 13 | # Test for multiple invalid
@@ -148,7 +148,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID200
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID200`
 11 | # Mixed valid and invalid
 12 | from typing import List  # noqa: F401, INVALID123
 13 | # Test for multiple invalid
@@ -168,7 +168,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID300
 17 | # Test for mixed code types
 18 | import json  # noqa: E402, INVALID400, V100
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID300`
 13 | # Test for multiple invalid
 14 | from collections import defaultdict  # noqa: INVALID100, INVALID200, F401
 15 | # Test for preserving valid codes when fixing
@@ -188,7 +188,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID400
 19 | # Test for rule redirects
 20 | import pandas as pd  # noqa: TCH002
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID400`
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
 17 | # Test for mixed code types
@@ -207,7 +207,7 @@ RUF102 [*] Invalid rule code in `# noqa`: V100
 19 | # Test for rule redirects
 20 | import pandas as pd  # noqa: TCH002
    |
-help: Remove the rule code
+help: Remove the rule code `V100`
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
 17 | # Test for mixed code types

crates/ruff_linter/src/rules/ruff/snapshots/ruff_linter__rules__ruff__tests__invalid_rule_code_external_rules.snap

@@ -10,7 +10,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID123
 3 | # External code
 4 | import re  # noqa: V123
   |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 1 | # Invalid code
   - import os  # noqa: INVALID123
 2 + import os  
@@ -28,7 +28,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID456
 8 | from itertools import product  # Preceeding comment # noqa: INVALID789
 9 | # Succeeding comment
   |
-help: Remove the rule code
+help: Remove the rule code `INVALID456`
 4  | import re  # noqa: V123
 5  | # Valid noqa
 6  | import sys  # noqa: E402
@@ -48,7 +48,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID789
  9 | # Succeeding comment
 10 | import math # noqa: INVALID000 # Succeeding comment
    |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 5  | # Valid noqa
 6  | import sys  # noqa: E402
 7  | from functools import cache  # Preceeding comment # noqa: F401, INVALID456
@@ -68,7 +68,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID000
 11 | # Mixed valid and invalid
 12 | from typing import List  # noqa: F401, INVALID123
    |
-help: Remove the rule code
+help: Remove the `# noqa` comment
 7  | from functools import cache  # Preceeding comment # noqa: F401, INVALID456
 8  | from itertools import product  # Preceeding comment # noqa: INVALID789
 9  | # Succeeding comment
@@ -88,7 +88,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID123
 13 | # Test for multiple invalid
 14 | from collections import defaultdict  # noqa: INVALID100, INVALID200, F401
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID123`
 9  | # Succeeding comment
 10 | import math # noqa: INVALID000 # Succeeding comment
 11 | # Mixed valid and invalid
@@ -108,7 +108,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID100
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID100`
 11 | # Mixed valid and invalid
 12 | from typing import List  # noqa: F401, INVALID123
 13 | # Test for multiple invalid
@@ -128,7 +128,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID200
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID200`
 11 | # Mixed valid and invalid
 12 | from typing import List  # noqa: F401, INVALID123
 13 | # Test for multiple invalid
@@ -148,7 +148,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID300
 17 | # Test for mixed code types
 18 | import json  # noqa: E402, INVALID400, V100
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID300`
 13 | # Test for multiple invalid
 14 | from collections import defaultdict  # noqa: INVALID100, INVALID200, F401
 15 | # Test for preserving valid codes when fixing
@@ -168,7 +168,7 @@ RUF102 [*] Invalid rule code in `# noqa`: INVALID400
 19 | # Test for rule redirects
 20 | import pandas as pd  # noqa: TCH002
    |
-help: Remove the rule code
+help: Remove the rule code `INVALID400`
 15 | # Test for preserving valid codes when fixing
 16 | from itertools import chain  # noqa: E402, INVALID300, F401
 17 | # Test for mixed code types

crates/ruff_linter/src/rules/ruff/snapshots/ruff_linter__rules__ruff__tests__range_suppressions.snap

@@ -7,7 +7,7 @@ source: crates/ruff_linter/src/rules/ruff/mod.rs
 
 --- Summary ---
 Removed: 15
-Added: 23
+Added: 20
 
 --- Removed ---
 E741 Ambiguous variable name: `I`
@@ -301,6 +301,7 @@ RUF100 [*] Unused suppression (non-enabled: `E501`)
    |     ^^^^^^^^^^^^^^^^^^^^^
 47 |     I = 1
 48 |     # ruff: enable[E501]
+   |     --------------------
    |
 help: Remove unused suppression
 43 | def f():
@@ -308,26 +309,10 @@ help: Remove unused suppression
 45 |     # logged to user
    -     # ruff: disable[E501]
 46 |     I = 1
-47 |     # ruff: enable[E501]
-48 | 
-
-
-RUF100 [*] Unused suppression (non-enabled: `E501`)
-  --> suppressions.py:48:5
-   |
-46 |     # ruff: disable[E501]
-47 |     I = 1
-48 |     # ruff: enable[E501]
-   |     ^^^^^^^^^^^^^^^^^^^^
-   |
-help: Remove unused suppression
-45 |     # logged to user
-46 |     # ruff: disable[E501]
-47 |     I = 1
    -     # ruff: enable[E501]
+47 | 
 48 | 
-49 | 
-50 | def f():
+49 | def f():
 
 
 RUF100 [*] Unused `noqa` directive (unused: `E741`, `F841`)
@@ -563,8 +548,11 @@ RUF102 [*] Invalid rule code in suppression: YF829
    |                     ^^^^^
 94 |     # ruff: disable[F841, RQW320]
 95 |     value = 0
+96 |     # ruff: enable[F841, RQW320]
+97 |     # ruff: enable[YF829]
+   |                    -----
    |
-help: Remove the rule code
+help: Remove the suppression comment
 90 | 
 91 | def f():
 92 |     # Unknown rule codes
@@ -572,6 +560,10 @@ help: Remove the rule code
 93 |     # ruff: disable[F841, RQW320]
 94 |     value = 0
 95 |     # ruff: enable[F841, RQW320]
+   -     # ruff: enable[YF829]
+96 | 
+97 | 
+98 | def f():
 
 
 RUF102 [*] Invalid rule code in suppression: RQW320
@@ -583,30 +575,15 @@ RUF102 [*] Invalid rule code in suppression: RQW320
    |                           ^^^^^^
 95 |     value = 0
 96 |     # ruff: enable[F841, RQW320]
+   |                          ------
+97 |     # ruff: enable[YF829]
    |
-help: Remove the rule code
+help: Remove the rule code `RQW320`
 91 | def f():
 92 |     # Unknown rule codes
 93 |     # ruff: disable[YF829]
    -     # ruff: disable[F841, RQW320]
 94 +     # ruff: disable[F841]
-95 |     value = 0
-96 |     # ruff: enable[F841, RQW320]
-97 |     # ruff: enable[YF829]
-
-
-RUF102 [*] Invalid rule code in suppression: RQW320
-  --> suppressions.py:96:26
-   |
-94 |     # ruff: disable[F841, RQW320]
-95 |     value = 0
-96 |     # ruff: enable[F841, RQW320]
-   |                          ^^^^^^
-97 |     # ruff: enable[YF829]
-   |
-help: Remove the rule code
-93 |     # ruff: disable[YF829]
-94 |     # ruff: disable[F841, RQW320]
 95 |     value = 0
    -     # ruff: enable[F841, RQW320]
 96 +     # ruff: enable[F841]
@@ -615,24 +592,6 @@ help: Remove the rule code
 99 | 
 
 
-RUF102 [*] Invalid rule code in suppression: YF829
-  --> suppressions.py:97:20
-   |
-95 |     value = 0
-96 |     # ruff: enable[F841, RQW320]
-97 |     # ruff: enable[YF829]
-   |                    ^^^^^
-   |
-help: Remove the rule code
-94 |     # ruff: disable[F841, RQW320]
-95 |     value = 0
-96 |     # ruff: enable[F841, RQW320]
-   -     # ruff: enable[YF829]
-97 | 
-98 | 
-99 | def f():
-
-
 RUF103 [*] Invalid suppression comment: missing suppression codes like `[E501, ...]`
    --> suppressions.py:109:5
     |

crates/ruff_linter/src/settings/types.rs

@@ -36,6 +36,7 @@ pub enum PythonVersion {
     Py312,
     Py313,
     Py314,
+    Py315,
 }
 
 impl Default for PythonVersion {
@@ -58,6 +59,7 @@ impl TryFrom<ast::PythonVersion> for PythonVersion {
             ast::PythonVersion::PY312 => Ok(Self::Py312),
             ast::PythonVersion::PY313 => Ok(Self::Py313),
             ast::PythonVersion::PY314 => Ok(Self::Py314),
+            ast::PythonVersion::PY315 => Ok(Self::Py315),
             _ => Err(format!("unrecognized python version {value}")),
         }
     }
@@ -88,6 +90,7 @@ impl PythonVersion {
             Self::Py312 => (3, 12),
             Self::Py313 => (3, 13),
             Self::Py314 => (3, 14),
+            Self::Py315 => (3, 15),
         }
     }
 }
@@ -604,13 +607,21 @@ impl TryFrom<String> for RequiredVersion {
     type Error = pep440_rs::VersionSpecifiersParseError;
 
     fn try_from(value: String) -> Result<Self, Self::Error> {
+        value.parse()
+    }
+}
+
+impl FromStr for RequiredVersion {
+    type Err = pep440_rs::VersionSpecifiersParseError;
+
+    fn from_str(value: &str) -> Result<Self, Self::Err> {
         // Treat `0.3.1` as `==0.3.1`, for backwards compatibility.
-        if let Ok(version) = pep440_rs::Version::from_str(&value) {
+        if let Ok(version) = pep440_rs::Version::from_str(value) {
             Ok(Self(VersionSpecifiers::from(
                 VersionSpecifier::equals_version(version),
             )))
         } else {
-            Ok(Self(VersionSpecifiers::from_str(&value)?))
+            Ok(Self(VersionSpecifiers::from_str(value)?))
         }
     }
 }

crates/ruff_linter/src/suppression.rs

@@ -13,7 +13,6 @@ use ruff_python_trivia::Cursor;
 use ruff_text_size::{Ranged, TextLen, TextRange, TextSize, TextSlice};
 use smallvec::{SmallVec, smallvec};
 
-use crate::Locator;
 use crate::checkers::ast::LintContext;
 use crate::codes::Rule;
 use crate::fix::edits::delete_comment;
@@ -24,6 +23,7 @@ use crate::rules::ruff::rules::{
     UnmatchedSuppressionComment, UnusedCodes, UnusedNOQA, UnusedNOQAKind, code_is_valid,
 };
 use crate::settings::LinterSettings;
+use crate::{Locator, Violation};
 
 #[derive(Clone, Debug, Eq, PartialEq)]
 enum SuppressionAction {
@@ -85,11 +85,39 @@ pub(crate) struct Suppression {
     /// Range for which the suppression applies
     range: TextRange,
 
-    /// Any comments associated with the suppression
-    comments: SmallVec<[SuppressionComment; 2]>,
-
     /// Whether this suppression actually suppressed a diagnostic
     used: Cell<bool>,
+
+    comments: DisableEnableComments,
+}
+
+impl Suppression {
+    fn codes(&self) -> &[TextRange] {
+        &self.comments.disable_comment().codes
+    }
+}
+
+#[derive(Debug)]
+pub(crate) enum DisableEnableComments {
+    /// An implicitly closed disable comment without a matching enable comment.
+    Disable(SuppressionComment),
+    /// A matching pair of disable and enable comments.
+    DisableEnable(SuppressionComment, SuppressionComment),
+}
+
+impl DisableEnableComments {
+    pub(crate) fn disable_comment(&self) -> &SuppressionComment {
+        match self {
+            DisableEnableComments::Disable(comment) => comment,
+            DisableEnableComments::DisableEnable(disable, _) => disable,
+        }
+    }
+    pub(crate) fn enable_comment(&self) -> Option<&SuppressionComment> {
+        match self {
+            DisableEnableComments::Disable(_) => None,
+            DisableEnableComments::DisableEnable(_, enable) => Some(enable),
+        }
+    }
 }
 
 #[derive(Copy, Clone, Debug)]
@@ -171,23 +199,17 @@ impl Suppressions {
             if !code_is_valid(&suppression.code, &context.settings().external) {
                 // InvalidRuleCode
                 if context.is_rule_enabled(Rule::InvalidRuleCode) {
-                    for comment in &suppression.comments {
-                        let (range, edit) = Suppressions::delete_code_or_comment(
-                            locator,
-                            suppression,
-                            comment,
-                            true,
-                        );
-                        context
-                            .report_diagnostic(
-                                InvalidRuleCode {
-                                    rule_code: suppression.code.to_string(),
-                                    kind: InvalidRuleCodeKind::Suppression,
-                                },
-                                range,
-                            )
-                            .set_fix(Fix::safe_edit(edit));
-                    }
+                    Suppressions::report_suppression(
+                        context,
+                        locator,
+                        suppression,
+                        true,
+                        InvalidRuleCode {
+                            rule_code: suppression.code.to_string(),
+                            kind: InvalidRuleCodeKind::Suppression,
+                            whole_comment: suppression.codes().len() == 1,
+                        },
+                    );
                 }
             } else if !suppression.used.get() {
                 // UnusedNOQA
@@ -197,42 +219,37 @@ impl Suppressions {
                     ) else {
                         continue; // "external" lint code, don't treat it as unused
                     };
-                    for comment in &suppression.comments {
-                        let (range, edit) = Suppressions::delete_code_or_comment(
-                            locator,
-                            suppression,
-                            comment,
-                            false,
-                        );
 
-                        let codes = if context.is_rule_enabled(rule) {
-                            UnusedCodes {
-                                unmatched: vec![suppression.code.to_string()],
-                                ..Default::default()
-                            }
-                        } else {
-                            UnusedCodes {
-                                disabled: vec![suppression.code.to_string()],
-                                ..Default::default()
-                            }
-                        };
+                    let codes = if context.is_rule_enabled(rule) {
+                        UnusedCodes {
+                            unmatched: vec![suppression.code.to_string()],
+                            ..Default::default()
+                        }
+                    } else {
+                        UnusedCodes {
+                            disabled: vec![suppression.code.to_string()],
+                            ..Default::default()
+                        }
+                    };
 
-                        context
-                            .report_diagnostic(
-                                UnusedNOQA {
-                                    codes: Some(codes),
-                                    kind: UnusedNOQAKind::Suppression,
-                                },
-                                range,
-                            )
-                            .set_fix(Fix::safe_edit(edit));
-                    }
+                    Suppressions::report_suppression(
+                        context,
+                        locator,
+                        suppression,
+                        false,
+                        UnusedNOQA {
+                            codes: Some(codes),
+                            kind: UnusedNOQAKind::Suppression,
+                        },
+                    );
                 }
-            } else if suppression.comments.len() == 1 {
+            } else if let DisableEnableComments::Disable(comment) = &suppression.comments {
                 // UnmatchedSuppressionComment
-                let range = suppression.comments[0].range;
-                if unmatched_ranges.insert(range) {
-                    context.report_diagnostic_if_enabled(UnmatchedSuppressionComment {}, range);
+                if unmatched_ranges.insert(comment.range) {
+                    context.report_diagnostic_if_enabled(
+                        UnmatchedSuppressionComment {},
+                        comment.range,
+                    );
                 }
             }
         }
@@ -267,6 +284,35 @@ impl Suppressions {
         }
     }
 
+    fn report_suppression<T: Violation>(
+        context: &LintContext,
+        locator: &Locator,
+        suppression: &Suppression,
+        highlight_only_code: bool,
+        kind: T,
+    ) {
+        let disable_comment = suppression.comments.disable_comment();
+        let (range, edit) = Suppressions::delete_code_or_comment(
+            locator,
+            suppression,
+            disable_comment,
+            highlight_only_code,
+        );
+        let mut diagnostic = context.report_diagnostic(kind, range);
+        if let Some(enable_comment) = suppression.comments.enable_comment() {
+            let (enable_range, enable_range_edit) = Suppressions::delete_code_or_comment(
+                locator,
+                suppression,
+                enable_comment,
+                highlight_only_code,
+            );
+            diagnostic.secondary_annotation("", enable_range);
+            diagnostic.set_fix(Fix::safe_edits(edit, [enable_range_edit]));
+        } else {
+            diagnostic.set_fix(Fix::safe_edit(edit));
+        }
+    }
+
     fn delete_code_or_comment(
         locator: &Locator<'_>,
         suppression: &Suppression,
@@ -424,7 +470,10 @@ impl<'a> SuppressionsBuilder<'a> {
                     self.valid.push(Suppression {
                         code: code.into(),
                         range: combined_range,
-                        comments: smallvec![comment.comment.clone(), other.comment.clone()],
+                        comments: DisableEnableComments::DisableEnable(
+                            comment.comment.clone(),
+                            other.comment.clone(),
+                        ),
                         used: false.into(),
                     });
                 }
@@ -441,7 +490,7 @@ impl<'a> SuppressionsBuilder<'a> {
                     self.valid.push(Suppression {
                         code: code.into(),
                         range: implicit_range,
-                        comments: smallvec![comment.comment.clone()],
+                        comments: DisableEnableComments::Disable(comment.comment.clone()),
                         used: false.into(),
                     });
                 }
@@ -643,7 +692,7 @@ mod tests {
     use insta::assert_debug_snapshot;
     use itertools::Itertools;
     use ruff_python_parser::{Mode, ParseOptions, parse};
-    use ruff_text_size::{TextRange, TextSize};
+    use ruff_text_size::{TextLen, TextRange, TextSize};
     use similar::DiffableStr;
 
     use crate::{
@@ -705,24 +754,22 @@ print('hello')
                 Suppression {
                     covered_source: "# ruff: disable[foo]\nprint('hello')\n# ruff: enable[foo]",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[foo]",
-                            action: Enable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[foo]",
+                        action: Enable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
                 },
             ],
             invalid: [],
@@ -751,30 +798,28 @@ def foo():
                 Suppression {
                     covered_source: "# ruff: disable[bar]\n    print('hello')\n\n",
                     code: "bar",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[bar]",
-                            action: Disable,
-                            codes: [
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[bar]",
+                        action: Disable,
+                        codes: [
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: None,
                 },
                 Suppression {
                     covered_source: "# ruff: disable[foo]\nprint('hello')\n\ndef foo():\n    # ruff: disable[bar]\n    print('hello')\n\n",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: None,
                 },
             ],
             invalid: [],
@@ -803,46 +848,42 @@ class Foo:
                 Suppression {
                     covered_source: "# ruff: disable[bar]\n        print('hello')\n        # ruff: enable[bar]",
                     code: "bar",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[bar]",
-                            action: Disable,
-                            codes: [
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[bar]",
-                            action: Enable,
-                            codes: [
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[bar]",
+                        action: Disable,
+                        codes: [
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[bar]",
+                        action: Enable,
+                        codes: [
+                            "bar",
+                        ],
+                        reason: "",
+                    },
                 },
                 Suppression {
                     covered_source: "# ruff: disable[foo]\n    def bar(self):\n        # ruff: disable[bar]\n        print('hello')\n        # ruff: enable[bar]\n    # ruff: enable[foo]",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[foo]",
-                            action: Enable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[foo]",
+                        action: Enable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
                 },
             ],
             invalid: [],
@@ -872,46 +913,42 @@ def foo():
                 Suppression {
                     covered_source: "# ruff: disable[foo]\n    print('hello')\n    # ruff: disable[bar]\n    print('hello')\n    # ruff: enable[foo]",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[foo]",
-                            action: Enable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[foo]",
+                        action: Enable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
                 },
                 Suppression {
                     covered_source: "# ruff: disable[bar]\n    print('hello')\n    # ruff: enable[foo]\n    print('hello')\n    # ruff: enable[bar]",
                     code: "bar",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[bar]",
-                            action: Disable,
-                            codes: [
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[bar]",
-                            action: Enable,
-                            codes: [
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[bar]",
+                        action: Disable,
+                        codes: [
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[bar]",
+                        action: Enable,
+                        codes: [
+                            "bar",
+                        ],
+                        reason: "",
+                    },
                 },
             ],
             invalid: [],
@@ -936,50 +973,46 @@ print('hello')
                 Suppression {
                     covered_source: "# ruff: disable[foo, bar]\nprint('hello')\n# ruff: enable[foo, bar]",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo, bar]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[foo, bar]",
-                            action: Enable,
-                            codes: [
-                                "foo",
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo, bar]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[foo, bar]",
+                        action: Enable,
+                        codes: [
+                            "foo",
+                            "bar",
+                        ],
+                        reason: "",
+                    },
                 },
                 Suppression {
                     covered_source: "# ruff: disable[foo, bar]\nprint('hello')\n# ruff: enable[foo, bar]",
                     code: "bar",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo, bar]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[foo, bar]",
-                            action: Enable,
-                            codes: [
-                                "foo",
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo, bar]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[foo, bar]",
+                        action: Enable,
+                        codes: [
+                            "foo",
+                            "bar",
+                        ],
+                        reason: "",
+                    },
                 },
             ],
             invalid: [],
@@ -1005,16 +1038,15 @@ print('world')
                 Suppression {
                     covered_source: "# ruff: disable[foo]\nprint('hello')\n# ruff: enable[bar]\nprint('world')\n",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: None,
                 },
             ],
             invalid: [
@@ -1051,32 +1083,30 @@ print('hello')
                 Suppression {
                     covered_source: "# ruff: disable[foo, bar]\nprint('hello')\n# ruff: enable[bar, foo]\n",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo, bar]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo, bar]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: None,
                 },
                 Suppression {
                     covered_source: "# ruff: disable[foo, bar]\nprint('hello')\n# ruff: enable[bar, foo]\n",
                     code: "bar",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo, bar]",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                                "bar",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo, bar]",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                            "bar",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: None,
                 },
             ],
             invalid: [
@@ -1116,38 +1146,35 @@ print('hello')
                 Suppression {
                     covered_source: "# ruff: disable[foo] first\nprint('hello')\n# ruff: disable[foo] second\nprint('hello')\n# ruff: enable[foo]",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo] first",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "first",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[foo]",
-                            action: Enable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo] first",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "first",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[foo]",
+                        action: Enable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "",
+                    },
                 },
                 Suppression {
                     covered_source: "# ruff: disable[foo] second\nprint('hello')\n# ruff: enable[foo]\n",
                     code: "foo",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[foo] second",
-                            action: Disable,
-                            codes: [
-                                "foo",
-                            ],
-                            reason: "second",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[foo] second",
+                        action: Disable,
+                        codes: [
+                            "foo",
+                        ],
+                        reason: "second",
+                    },
+                    enable_comment: None,
                 },
             ],
             invalid: [],
@@ -1189,100 +1216,92 @@ def bar():
                 Suppression {
                     covered_source: "# ruff: disable[delta] unmatched\n        pass\n    # ruff: enable[beta,gamma]\n# ruff: enable[alpha]\n\n# ruff: disable  # parse error!\n",
                     code: "delta",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[delta] unmatched",
-                            action: Disable,
-                            codes: [
-                                "delta",
-                            ],
-                            reason: "unmatched",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[delta] unmatched",
+                        action: Disable,
+                        codes: [
+                            "delta",
+                        ],
+                        reason: "unmatched",
+                    },
+                    enable_comment: None,
                 },
                 Suppression {
                     covered_source: "# ruff: disable[beta,gamma]\n    if True:\n        # ruff: disable[delta] unmatched\n        pass\n    # ruff: enable[beta,gamma]",
                     code: "beta",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[beta,gamma]",
-                            action: Disable,
-                            codes: [
-                                "beta",
-                                "gamma",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[beta,gamma]",
-                            action: Enable,
-                            codes: [
-                                "beta",
-                                "gamma",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[beta,gamma]",
+                        action: Disable,
+                        codes: [
+                            "beta",
+                            "gamma",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[beta,gamma]",
+                        action: Enable,
+                        codes: [
+                            "beta",
+                            "gamma",
+                        ],
+                        reason: "",
+                    },
                 },
                 Suppression {
                     covered_source: "# ruff: disable[beta,gamma]\n    if True:\n        # ruff: disable[delta] unmatched\n        pass\n    # ruff: enable[beta,gamma]",
                     code: "gamma",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[beta,gamma]",
-                            action: Disable,
-                            codes: [
-                                "beta",
-                                "gamma",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[beta,gamma]",
-                            action: Enable,
-                            codes: [
-                                "beta",
-                                "gamma",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[beta,gamma]",
+                        action: Disable,
+                        codes: [
+                            "beta",
+                            "gamma",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[beta,gamma]",
+                        action: Enable,
+                        codes: [
+                            "beta",
+                            "gamma",
+                        ],
+                        reason: "",
+                    },
                 },
                 Suppression {
                     covered_source: "# ruff: disable[zeta] unmatched\n    pass\n# ruff: enable[zeta] underindented\n    pass\n",
                     code: "zeta",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[zeta] unmatched",
-                            action: Disable,
-                            codes: [
-                                "zeta",
-                            ],
-                            reason: "unmatched",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[zeta] unmatched",
+                        action: Disable,
+                        codes: [
+                            "zeta",
+                        ],
+                        reason: "unmatched",
+                    },
+                    enable_comment: None,
                 },
                 Suppression {
                     covered_source: "# ruff: disable[alpha]\ndef foo():\n    # ruff: disable[beta,gamma]\n    if True:\n        # ruff: disable[delta] unmatched\n        pass\n    # ruff: enable[beta,gamma]\n# ruff: enable[alpha]",
                     code: "alpha",
-                    comments: [
-                        SuppressionComment {
-                            text: "# ruff: disable[alpha]",
-                            action: Disable,
-                            codes: [
-                                "alpha",
-                            ],
-                            reason: "",
-                        },
-                        SuppressionComment {
-                            text: "# ruff: enable[alpha]",
-                            action: Enable,
-                            codes: [
-                                "alpha",
-                            ],
-                            reason: "",
-                        },
-                    ],
+                    disable_comment: SuppressionComment {
+                        text: "# ruff: disable[alpha]",
+                        action: Disable,
+                        codes: [
+                            "alpha",
+                        ],
+                        reason: "",
+                    },
+                    enable_comment: SuppressionComment {
+                        text: "# ruff: enable[alpha]",
+                        action: Enable,
+                        codes: [
+                            "alpha",
+                        ],
+                        reason: "",
+                    },
                 },
             ],
             invalid: [
@@ -1532,10 +1551,8 @@ def bar():
     #[test]
     fn comment_attributes() {
         let source = "# ruff: disable[foo, bar] hello world";
-        let mut parser = SuppressionParser::new(
-            source,
-            TextRange::new(0.into(), TextSize::try_from(source.len()).unwrap()),
-        );
+        let mut parser =
+            SuppressionParser::new(source, TextRange::new(0.into(), source.text_len()));
         let comment = parser.parse_comment().unwrap();
         assert_eq!(comment.action, SuppressionAction::Disable);
         assert_eq!(
@@ -1554,12 +1571,12 @@ def bar():
         source: &'_ str,
     ) -> Result<DebugSuppressionComment<'_>, ParseError> {
         let offset = TextSize::new(source.find('#').unwrap_or(0).try_into().unwrap());
-        let mut parser = SuppressionParser::new(
-            source,
-            TextRange::new(offset, TextSize::try_from(source.len()).unwrap()),
-        );
+        let mut parser = SuppressionParser::new(source, TextRange::new(offset, source.text_len()));
         match parser.parse_comment() {
-            Ok(comment) => Ok(DebugSuppressionComment { source, comment }),
+            Ok(comment) => Ok(DebugSuppressionComment {
+                source,
+                comment: Some(comment),
+            }),
             Err(error) => Err(error),
         }
     }
@@ -1639,16 +1656,18 @@ def bar():
                 .field("covered_source", &&self.source[self.suppression.range])
                 .field("code", &self.suppression.code)
                 .field(
-                    "comments",
-                    &self
-                        .suppression
-                        .comments
-                        .iter()
-                        .map(|comment| DebugSuppressionComment {
-                            source: self.source,
-                            comment: comment.clone(),
-                        })
-                        .collect_vec(),
+                    "disable_comment",
+                    &DebugSuppressionComment {
+                        source: self.source,
+                        comment: Some(self.suppression.comments.disable_comment().clone()),
+                    },
+                )
+                .field(
+                    "enable_comment",
+                    &DebugSuppressionComment {
+                        source: self.source,
+                        comment: self.suppression.comments.enable_comment().cloned(),
+                    },
                 )
                 .finish()
         }
@@ -1667,7 +1686,7 @@ def bar():
                     "comment",
                     &DebugSuppressionComment {
                         source: self.source,
-                        comment: self.invalid.comment.clone(),
+                        comment: Some(self.invalid.comment.clone()),
                     },
                 )
                 .finish()
@@ -1690,23 +1709,27 @@ def bar():
 
     struct DebugSuppressionComment<'a> {
         source: &'a str,
-        comment: SuppressionComment,
+        comment: Option<SuppressionComment>,
     }
 
     impl fmt::Debug for DebugSuppressionComment<'_> {
         fn fmt(&self, f: &mut Formatter<'_>) -> fmt::Result {
-            f.debug_struct("SuppressionComment")
-                .field("text", &&self.source[self.comment.range])
-                .field("action", &self.comment.action)
-                .field(
-                    "codes",
-                    &DebugCodes {
-                        source: self.source,
-                        codes: &self.comment.codes,
-                    },
-                )
-                .field("reason", &&self.source[self.comment.reason])
-                .finish()
+            match &self.comment {
+                Some(comment) => f
+                    .debug_struct("SuppressionComment")
+                    .field("text", &&self.source[comment.range])
+                    .field("action", &comment.action)
+                    .field(
+                        "codes",
+                        &DebugCodes {
+                            source: self.source,
+                            codes: &comment.codes,
+                        },
+                    )
+                    .field("reason", &&self.source[comment.reason])
+                    .finish(),
+                None => f.debug_tuple("None").finish(),
+            }
         }
     }
 

crates/ruff_python_ast/Cargo.toml

@@ -28,7 +28,6 @@ bitflags = { workspace = true }
 compact_str = { workspace = true }
 get-size2 = { workspace = true, optional = true }
 is-macro = { workspace = true }
-itertools = { workspace = true }
 memchr = { workspace = true }
 rustc-hash = { workspace = true }
 salsa = { workspace = true, optional = true }

crates/ruff_python_ast/src/nodes.rs

@@ -14,7 +14,6 @@ use std::slice::{Iter, IterMut};
 use std::sync::OnceLock;
 
 use bitflags::bitflags;
-use itertools::Itertools;
 
 use ruff_text_size::{Ranged, TextLen, TextRange, TextSize};
 
@@ -3380,10 +3379,13 @@ impl Arguments {
     /// 2
     /// {'4': 5}
     /// ```
-    pub fn arguments_source_order(&self) -> impl Iterator<Item = ArgOrKeyword<'_>> {
-        let args = self.args.iter().map(ArgOrKeyword::Arg);
-        let keywords = self.keywords.iter().map(ArgOrKeyword::Keyword);
-        args.merge_by(keywords, |left, right| left.start() <= right.start())
+    pub fn arguments_source_order(&self) -> ArgumentsSourceOrder<'_> {
+        ArgumentsSourceOrder {
+            args: &self.args,
+            keywords: &self.keywords,
+            next_arg: 0,
+            next_keyword: 0,
+        }
     }
 
     pub fn inner_range(&self) -> TextRange {
@@ -3399,6 +3401,38 @@ impl Arguments {
     }
 }
 
+/// The iterator returned by [`Arguments::arguments_source_order`].
+#[derive(Clone)]
+pub struct ArgumentsSourceOrder<'a> {
+    args: &'a [Expr],
+    keywords: &'a [Keyword],
+    next_arg: usize,
+    next_keyword: usize,
+}
+
+impl<'a> Iterator for ArgumentsSourceOrder<'a> {
+    type Item = ArgOrKeyword<'a>;
+
+    fn next(&mut self) -> Option<Self::Item> {
+        let arg = self.args.get(self.next_arg);
+        let keyword = self.keywords.get(self.next_keyword);
+
+        if let Some(arg) = arg
+            && keyword.is_none_or(|keyword| arg.start() <= keyword.start())
+        {
+            self.next_arg += 1;
+            Some(ArgOrKeyword::Arg(arg))
+        } else if let Some(keyword) = keyword {
+            self.next_keyword += 1;
+            Some(ArgOrKeyword::Keyword(keyword))
+        } else {
+            None
+        }
+    }
+}
+
+impl FusedIterator for ArgumentsSourceOrder<'_> {}
+
 /// An AST node used to represent a sequence of type parameters.
 ///
 /// For example, given:

crates/ruff_python_ast/src/python_version.rs

@@ -35,6 +35,10 @@ impl PythonVersion {
         major: 3,
         minor: 14,
     };
+    pub const PY315: PythonVersion = PythonVersion {
+        major: 3,
+        minor: 15,
+    };
 
     pub fn iter() -> impl Iterator<Item = PythonVersion> {
         [
@@ -46,6 +50,7 @@ impl PythonVersion {
             PythonVersion::PY312,
             PythonVersion::PY313,
             PythonVersion::PY314,
+            PythonVersion::PY315,
         ]
         .into_iter()
     }
@@ -61,7 +66,7 @@ impl PythonVersion {
 
     /// The latest Python version supported in preview
     pub fn latest_preview() -> Self {
-        let latest_preview = Self::PY314;
+        let latest_preview = Self::PY315;
         debug_assert!(latest_preview >= Self::latest());
         latest_preview
     }

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtonoff.py

@@ -91,20 +91,22 @@ def example(session):
         .all()
     # fmt: on
 def off_and_on_without_data():
-    """All comments here are technically on the same prefix.
-
-    The comments between will be formatted. This is a known limitation.
-    """
+    """Test that comment-only fmt:off/on blocks preserve formatting."""
+    # fmt: off
+            #should not be formatted
+    # fmt: on
     # fmt: off
 
-
-        #hey, that won't work
-
+        #should not be formatted
 
     # fmt: on
+    # fmt: off
+            #should not be formatted
+        #should not be formatted #also should not be formatted
+    # fmt: on
     pass
-def on_and_off_broken():
-    """Another known limitation."""
+def on_and_off_with_comment_only_blocks():
+    """Test that fmt:off/on works with multiple directives and comment-only blocks."""
     # fmt: on
     # fmt: off
     this=should.not_be.formatted()
@@ -113,7 +115,16 @@ def on_and_off_broken():
     now . considers . multiple . fmt . directives . within . one . prefix
     # fmt: on
     # fmt: off
-        # ...but comments still get reformatted even though they should not be
+            #should not be formatted
+    # fmt: on
+    # fmt: off
+
+        #should not be formatted
+
+    # fmt: on
+    # fmt: off
+            #should not be formatted
+        #should not be formatted #also should not be formatted
     # fmt: on
 def long_lines():
     if True:
@@ -178,6 +189,50 @@ cfg.rule(
     # fmt: on
     xxxxxxxxxx_xxxxxxxxxxx_xxxxxxx_xxxxxxxxx=5
 )
+
+# Test comment-only blocks at file level with various spacing patterns
+# fmt: off
+ #nospace
+ # twospaces
+# fmt: on
+
+
+# fmt: off
+#nospaceatall
+  #extraspaces
+   #evenmorespaces
+# fmt: on
+
+
+# fmt: off
+# fmt: on
+
+
+# fmt: off
+#SBATCH --job-name=test
+#SBATCH --output=test.out
+# fmt: on
+
+
+# fmt: off
+ #first
+
+ #second
+# fmt: on
+
+
+# fmt: off
+  #!@#$%^&*()
+   #<=>+-*/
+# fmt: on
+
+
+# fmt: off
+ #x=1+2
+  #y  =  3
+   #z    =    4
+# fmt: on
+
 # fmt: off
 yield  'hello'
 # No formatting to the end of the file

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtonoff.py.expect

@@ -112,29 +112,42 @@ def example(session):
 
 
 def off_and_on_without_data():
-    """All comments here are technically on the same prefix.
-
-    The comments between will be formatted. This is a known limitation.
-    """
+    """Test that comment-only fmt:off/on blocks preserve formatting."""
+    # fmt: off
+            #should not be formatted
+    # fmt: on
     # fmt: off
 
-    # hey, that won't work
+        #should not be formatted
 
     # fmt: on
+    # fmt: off
+            #should not be formatted
+        #should not be formatted #also should not be formatted
+    # fmt: on
     pass
 
 
-def on_and_off_broken():
-    """Another known limitation."""
+def on_and_off_with_comment_only_blocks():
+    """Test that fmt:off/on works with multiple directives and comment-only blocks."""
     # fmt: on
     # fmt: off
     this=should.not_be.formatted()
     and_=indeed . it  is  not  formatted
     because . the . handling . inside . generate_ignored_nodes()
     now . considers . multiple . fmt . directives . within . one . prefix
+
+    # fmt: off
+            #should not be formatted
     # fmt: on
     # fmt: off
-    # ...but comments still get reformatted even though they should not be
+
+        #should not be formatted
+
+    # fmt: on
+    # fmt: off
+            #should not be formatted
+        #should not be formatted #also should not be formatted
     # fmt: on
 
 
@@ -211,6 +224,50 @@ cfg.rule(
     # fmt: on
     xxxxxxxxxx_xxxxxxxxxxx_xxxxxxx_xxxxxxxxx=5,
 )
+
+# Test comment-only blocks at file level with various spacing patterns
+# fmt: off
+ #nospace
+ # twospaces
+# fmt: on
+
+
+# fmt: off
+#nospaceatall
+  #extraspaces
+   #evenmorespaces
+# fmt: on
+
+
+# fmt: off
+# fmt: on
+
+
+# fmt: off
+#SBATCH --job-name=test
+#SBATCH --output=test.out
+# fmt: on
+
+
+# fmt: off
+ #first
+
+ #second
+# fmt: on
+
+
+# fmt: off
+  #!@#$%^&*()
+   #<=>+-*/
+# fmt: on
+
+
+# fmt: off
+ #x=1+2
+  #y  =  3
+   #z    =    4
+# fmt: on
+
 # fmt: off
 yield  'hello'
 # No formatting to the end of the file

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip10.py

@@ -1,8 +1,21 @@
 def foo(): return "mock"  # fmt: skip
 if True: print("yay")  # fmt: skip
 for i in range(10): print(i)  # fmt: skip
+if True: print("this"); print("that")  # fmt: skip
+while True: print("loop"); break  # fmt: skip
+for x in [1, 2]: print(x); print("done")  # fmt: skip
+def f(x: int): return x # fmt: skip
 
 j =     1 # fmt: skip
 while j < 10: j += 1  # fmt: skip
 
 b = [c for c in "A very long string that would normally generate some kind of collapse, since it is this long"] # fmt: skip
+
+v = (
+    foo_dict  # fmt: skip
+    .setdefault("a", {})
+    .setdefault("b", {})
+    .setdefault("c", {})
+    .setdefault("d", {})
+    .setdefault("e", {})
+)

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip10.py.expect

@@ -1,8 +1,21 @@
 def foo(): return "mock"  # fmt: skip
 if True: print("yay")  # fmt: skip
 for i in range(10): print(i)  # fmt: skip
+if True: print("this"); print("that")  # fmt: skip
+while True: print("loop"); break  # fmt: skip
+for x in [1, 2]: print(x); print("done")  # fmt: skip
+def f(x: int): return x # fmt: skip
 
 j =     1 # fmt: skip
 while j < 10: j += 1  # fmt: skip
 
 b = [c for c in "A very long string that would normally generate some kind of collapse, since it is this long"] # fmt: skip
+
+v = (
+    foo_dict  # fmt: skip
+    .setdefault("a", {})
+    .setdefault("b", {})
+    .setdefault("c", {})
+    .setdefault("d", {})
+    .setdefault("e", {})
+)

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip11.py

@@ -4,3 +4,84 @@ def foo():
 
 # comment 1  # fmt: skip
 # comment 2
+
+[
+    (1, 2),
+    # # fmt: off
+    # (3,
+    #    4),
+    # # fmt: on
+    (5, 6),
+]
+
+[
+    (1, 2),
+    # # fmt: off
+    # (3,
+    #    4),
+    # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    # (3,
+    #    4),
+    # # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    # (3,
+    #    4),
+    # fmt: on
+    (5, 6),
+]
+
+[
+    (1, 2),
+    # # fmt: off
+    (3,
+       4),
+    # # fmt: on
+    (5, 6),
+]
+
+[
+    (1, 2),
+    # # fmt: off
+    (3,
+       4),
+    # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    (3,
+       4),
+    # # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    (3,
+       4),
+    # fmt: on
+    (5, 6),
+]
+
+
+if False:
+    # fmt: off # some other comment
+    pass

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip11.py.expect

@@ -4,3 +4,84 @@ def foo():
 
 # comment 1  # fmt: skip
 # comment 2
+
+[
+    (1, 2),
+    # # fmt: off
+    # (3,
+    #    4),
+    # # fmt: on
+    (5, 6),
+]
+
+[
+    (1, 2),
+    # # fmt: off
+    # (3,
+    #    4),
+    # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    # (3,
+    #    4),
+    # # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    # (3,
+    #    4),
+    # fmt: on
+    (5, 6),
+]
+
+[
+    (1, 2),
+    # # fmt: off
+    (3,
+       4),
+    # # fmt: on
+    (5, 6),
+]
+
+[
+    (1, 2),
+    # # fmt: off
+    (3,
+       4),
+    # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    (3,
+       4),
+    # # fmt: on
+    (5, 6),
+]
+
+
+[
+    (1, 2),
+    # fmt: off
+    (3,
+       4),
+    # fmt: on
+    (5, 6),
+]
+
+
+if False:
+    # fmt: off # some other comment
+    pass

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip12.options.json

@@ -0,0 +1 @@
+{"preview": "enabled"}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip12.py

@@ -0,0 +1,8 @@
+with open("file.txt") as f:    content = f.read() # fmt: skip
+
+# Ideally, only the last line would be ignored
+# But ignoring only part of the asexpr_test causes a parse error
+# Same with ignoring the asexpr_test without also ignoring the entire with_stmt
+with open   (
+    "file.txt"   ,
+) as f:    content = f.read() # fmt: skip

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip12.py.expect

@@ -0,0 +1,8 @@
+with open("file.txt") as f:    content = f.read() # fmt: skip
+
+# Ideally, only the last line would be ignored
+# But ignoring only part of the asexpr_test causes a parse error
+# Same with ignoring the asexpr_test without also ignoring the entire with_stmt
+with open   (
+    "file.txt"   ,
+) as f:    content = f.read() # fmt: skip

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip13.options.json

@@ -0,0 +1 @@
+{"preview": "enabled"}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip13.py

@@ -0,0 +1,28 @@
+t = (
+    {"foo": "very long string", "bar": "another very long string", "baz": "we should run out of space by now"},  # fmt: skip
+    {"foo": "bar"},
+)
+
+t = (
+    {
+        "foo": "very long string",
+        "bar": "another very long string",
+        "baz": "we should run out of space by now",
+    },  # fmt: skip
+    {"foo": "bar"},
+)
+
+
+t = (
+    {"foo": "very long string", "bar": "another very long string", "baz": "we should run out of space by now"},  # fmt: skip
+    {"foo": "bar",},
+)
+
+t = (
+    {
+        "foo": "very long string",
+        "bar": "another very long string",
+        "baz": "we should run out of space by now",
+    },  # fmt: skip
+    {"foo": "bar",},
+)

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip13.py.expect

@@ -0,0 +1,32 @@
+t = (
+    {"foo": "very long string", "bar": "another very long string", "baz": "we should run out of space by now"},  # fmt: skip
+    {"foo": "bar"},
+)
+
+t = (
+    {
+        "foo": "very long string",
+        "bar": "another very long string",
+        "baz": "we should run out of space by now",
+    },  # fmt: skip
+    {"foo": "bar"},
+)
+
+
+t = (
+    {"foo": "very long string", "bar": "another very long string", "baz": "we should run out of space by now"},  # fmt: skip
+    {
+        "foo": "bar",
+    },
+)
+
+t = (
+    {
+        "foo": "very long string",
+        "bar": "another very long string",
+        "baz": "we should run out of space by now",
+    },  # fmt: skip
+    {
+        "foo": "bar",
+    },
+)

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip7.py

@@ -1,4 +1,4 @@
 a =     "this is some code"
-b =     5  #fmt:skip
+b =     5          # fmt:skip
 c = 9  #fmt: skip
-d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  #fmt:skip
+d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  #            fmt:skip

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip7.py.expect

@@ -1,4 +1,4 @@
 a = "this is some code"
-b =     5  # fmt:skip
-c = 9  # fmt: skip
-d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  # fmt:skip
+b =     5          # fmt:skip
+c = 9  #fmt: skip
+d = "thisisasuperlongstringthisisasuperlongstringthisisasuperlongstringthisisasuperlongstring"  #            fmt:skip

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip_multiple_in_clause.py

@@ -0,0 +1,19 @@
+# Multiple fmt: skip in multi-part if-clause
+class ClassWithALongName:
+    Constant1 = 1
+    Constant2 = 2
+    Constant3 = 3
+
+
+def test():
+    if (
+        "cond1" == "cond1"
+        and "cond2" == "cond2"
+        and 1 in (
+            ClassWithALongName.Constant1,
+            ClassWithALongName.Constant2,
+            ClassWithALongName.Constant3, # fmt: skip
+        ) # fmt: skip
+    ):
+        return True
+    return False

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip_multiple_in_clause.py.expect

@@ -0,0 +1,19 @@
+# Multiple fmt: skip in multi-part if-clause
+class ClassWithALongName:
+    Constant1 = 1
+    Constant2 = 2
+    Constant3 = 3
+
+
+def test():
+    if (
+        "cond1" == "cond1"
+        and "cond2" == "cond2"
+        and 1 in (
+            ClassWithALongName.Constant1,
+            ClassWithALongName.Constant2,
+            ClassWithALongName.Constant3, # fmt: skip
+        ) # fmt: skip
+    ):
+        return True
+    return False

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip_multiple_strings.py

@@ -0,0 +1,35 @@
+# Multiple fmt: skip on string literals
+a = (
+    "this should "  # fmt: skip
+    "be fine"
+)
+
+b = (
+    "this is "  # fmt: skip
+    "not working"  # fmt: skip
+)
+
+c = (
+    "and neither "  # fmt: skip
+    "is this "  # fmt: skip
+    "working"
+)
+
+d = (
+    "nor "
+    "is this "  # fmt: skip
+    "working"  # fmt: skip
+)
+
+e = (
+    "and this "  # fmt: skip
+    "is definitely "
+    "not working"  # fmt: skip
+)
+
+# Dictionary entries with fmt: skip (covers issue with long lines)
+hotkeys = {
+    "editor:swap-line-down": [{"key": "ArrowDown", "modifiers": ["Alt", "Mod"]}],  # fmt: skip
+    "editor:swap-line-up":   [{"key": "ArrowUp",   "modifiers": ["Alt", "Mod"]}],  # fmt: skip
+    "editor:toggle-source":  [{"key": "S",         "modifiers": ["Alt", "Mod"]}],  # fmt: skip
+}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/fmtskip_multiple_strings.py.expect

@@ -0,0 +1,35 @@
+# Multiple fmt: skip on string literals
+a = (
+    "this should "  # fmt: skip
+    "be fine"
+)
+
+b = (
+    "this is "  # fmt: skip
+    "not working"  # fmt: skip
+)
+
+c = (
+    "and neither "  # fmt: skip
+    "is this "  # fmt: skip
+    "working"
+)
+
+d = (
+    "nor "
+    "is this "  # fmt: skip
+    "working"  # fmt: skip
+)
+
+e = (
+    "and this "  # fmt: skip
+    "is definitely "
+    "not working"  # fmt: skip
+)
+
+# Dictionary entries with fmt: skip (covers issue with long lines)
+hotkeys = {
+    "editor:swap-line-down": [{"key": "ArrowDown", "modifiers": ["Alt", "Mod"]}],  # fmt: skip
+    "editor:swap-line-up":   [{"key": "ArrowUp",   "modifiers": ["Alt", "Mod"]}],  # fmt: skip
+    "editor:toggle-source":  [{"key": "S",         "modifiers": ["Alt", "Mod"]}],  # fmt: skip
+}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/jupytext_markdown_fmt.py

@@ -0,0 +1,24 @@
+# Test that Jupytext markdown comments are preserved before fmt:off/on blocks
+# %% [markdown]
+
+# fmt: off
+# fmt: on
+
+# Also test with other comments
+# Some comment
+# %% [markdown]
+# Another comment
+
+# fmt: off
+x = 1
+# fmt: on
+
+# Test multiple markdown comments
+# %% [markdown]
+# First markdown
+# %% [code]
+# Code cell
+
+# fmt: off
+y = 2
+# fmt: on

crates/ruff_python_formatter/resources/test/fixtures/black/cases/jupytext_markdown_fmt.py.expect

@@ -0,0 +1,24 @@
+# Test that Jupytext markdown comments are preserved before fmt:off/on blocks
+# %% [markdown]
+
+# fmt: off
+# fmt: on
+
+# Also test with other comments
+# Some comment
+# %% [markdown]
+# Another comment
+
+# fmt: off
+x = 1
+# fmt: on
+
+# Test multiple markdown comments
+# %% [markdown]
+# First markdown
+# %% [code]
+# Code cell
+
+# fmt: off
+y = 2
+# fmt: on

crates/ruff_python_formatter/resources/test/fixtures/black/cases/pep_750.options.json

@@ -0,0 +1 @@
+{"target_version": "3.14"}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/pep_750.py

@@ -0,0 +1,40 @@
+x = t"foo"
+x = t'foo {{ {2 + 2}bar {{ baz'
+
+x = t"foo {f'abc'} bar"
+
+x = t"""foo {{ a
+    foo {2 + 2}bar {{ baz
+
+    x = f"foo {{ {
+        2 + 2  # comment
+    }bar"
+
+    {{ baz
+
+    }} buzz
+
+    {print("abc" + "def"
+)}
+abc"""
+
+t'{(abc:=10)}'
+
+t'''This is a really long string, but just make sure that you reflow tstrings {
+    2+2:d
+}'''
+t'This is a really long string, but just make sure that you reflow tstrings correctly {2+2:d}'
+
+t"{     2      +     2    =    }"
+
+t'{
+X
+!r
+}'
+
+tr'\{{\}}'
+
+t'''
+    WITH {f'''
+    {1}_cte AS ()'''}
+'''

crates/ruff_python_formatter/resources/test/fixtures/black/cases/pep_750.py.expect

@@ -0,0 +1,40 @@
+x = t"foo"
+x = t"foo {{ {2 + 2}bar {{ baz"
+
+x = t"foo {f'abc'} bar"
+
+x = t"""foo {{ a
+    foo {2 + 2}bar {{ baz
+
+    x = f"foo {{ {
+        2 + 2  # comment
+    }bar"
+
+    {{ baz
+
+    }} buzz
+
+    {print("abc" + "def"
+)}
+abc"""
+
+t"{(abc:=10)}"
+
+t"""This is a really long string, but just make sure that you reflow tstrings {
+    2+2:d
+}"""
+t"This is a really long string, but just make sure that you reflow tstrings correctly {2+2:d}"
+
+t"{     2      +     2    =    }"
+
+t"{
+X
+!r
+}"
+
+rt"\{{\}}"
+
+t"""
+    WITH {f'''
+    {1}_cte AS ()'''}
+"""

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_fmtpass_imports.options.json

@@ -0,0 +1 @@
+{"preview": "enabled"}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_fmtpass_imports.py

@@ -0,0 +1,19 @@
+# Regression test for https://github.com/psf/black/issues/3438
+
+import ast
+import collections  # fmt: skip
+import dataclasses
+# fmt: off
+import os
+# fmt: on
+import pathlib
+
+import re  # fmt: skip
+import secrets
+
+# fmt: off
+import sys
+# fmt: on
+
+import tempfile
+import zoneinfo

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_fmtpass_imports.py.expect

@@ -0,0 +1,19 @@
+# Regression test for https://github.com/psf/black/issues/3438
+
+import ast
+import collections  # fmt: skip
+import dataclasses
+# fmt: off
+import os
+# fmt: on
+import pathlib
+
+import re  # fmt: skip
+import secrets
+
+# fmt: off
+import sys
+# fmt: on
+
+import tempfile
+import zoneinfo

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_multiline_strings.py

@@ -156,24 +156,6 @@ Please use `--build-option` instead,
 `--global-option` is reserved to flags like `--verbose` or `--quiet`.
 """
 
-this_will_become_one_line = (
-    "a"
-    "b"
-    "c"
-)
-
-this_will_stay_on_three_lines = (
-    "a"  # comment
-    "b"
-    "c"
-)
-
-this_will_also_become_one_line = (  # comment
-    "a"
-    "b"
-    "c"
-)
-
 assert some_var == expected_result, """
 test
 """

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_multiline_strings.py.expect

@@ -198,16 +198,6 @@ Please use `--build-option` instead,
 `--global-option` is reserved to flags like `--verbose` or `--quiet`.
 """
 
-this_will_become_one_line = "abc"
-
-this_will_stay_on_three_lines = (
-    "a"  # comment
-    "b"
-    "c"
-)
-
-this_will_also_become_one_line = "abc"  # comment
-
 assert some_var == expected_result, """
 test
 """

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_standardize_type_comments.options.json

@@ -0,0 +1 @@
+{"preview": "enabled"}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_standardize_type_comments.py

@@ -0,0 +1,10 @@
+def foo(
+    a, #type:int
+    b, #type: str
+    c, # type: List[int]
+    d, #  type:  Dict[int, str]
+    e, #       type:     ignore
+    f, # type : ignore
+    g, #  type : ignore
+):
+    pass

crates/ruff_python_formatter/resources/test/fixtures/black/cases/preview_standardize_type_comments.py.expect

@@ -0,0 +1,10 @@
+def foo(
+    a,  # type: int
+    b,  # type: str
+    c,  # type: List[int]
+    d,  # type: Dict[int, str]
+    e,  # type: ignore
+    f,  # type : ignore
+    g,  #  type : ignore
+):
+    pass

crates/ruff_python_formatter/resources/test/fixtures/black/cases/remove_parens_from_lhs.options.json

@@ -0,0 +1 @@
+{"preview": "enabled"}

crates/ruff_python_formatter/resources/test/fixtures/black/cases/remove_parens_from_lhs.py

@@ -0,0 +1,16 @@
+# Remove unnecessary parentheses from LHS of assignments
+
+
+def a():
+    return [1, 2, 3]
+
+
+# Single variable with unnecessary parentheses
+(b) = a()[0]
+
+# Tuple unpacking with unnecessary parentheses
+(c, *_) = a()
+
+# These should not be changed - parentheses are necessary
+(d,) = a()  # single-element tuple
+e = (1 + 2) * 3  # RHS has precedence needs

crates/ruff_python_formatter/resources/test/fixtures/black/cases/remove_parens_from_lhs.py.expect

@@ -0,0 +1,16 @@
+# Remove unnecessary parentheses from LHS of assignments
+
+
+def a():
+    return [1, 2, 3]
+
+
+# Single variable with unnecessary parentheses
+b = a()[0]
+
+# Tuple unpacking with unnecessary parentheses
+c, *_ = a()
+
+# These should not be changed - parentheses are necessary
+(d,) = a()  # single-element tuple
+e = (1 + 2) * 3  # RHS has precedence needs