feat: support uv.lock as version-file (#379)

Adds `uv.lock` as a supported `version-file` format, alongside the
existing
`pyproject.toml` and `requirements.txt`. A `uv.lock` pins the exact
resolved
ruff version, so reading it gives a reproducible install that matches
the
project's lockfile — the single source of truth — instead of the
lower-bound /
range typically declared in `pyproject.toml`.

The parser reads the `[[package]]` entry whose `name` is `ruff` and
returns its
`version`. If ruff is absent or the file cannot be parsed, the action
warns and
falls back to `latest` (same behaviour as the other formats).

Validation:
- `npm run all` — tsc typecheck clean, biome clean, dist rebuilt, jest
65/65 pass
- Added unit tests (`__tests__/version/file-parser.test.ts`) + a
`uv.lock` fixture
- Added an integration job (`test-default-version-from-uv-lock`) that
runs the
  action against the fixture and asserts ruff 0.9.5 is installed

closes #375

.github/workflows/test.yml

@@ -280,6 +280,25 @@ jobs:
           fi
         env:
           RUFF_VERSION: ${{ steps.ruff-action.outputs.ruff-version }}
+  test-default-version-from-uv-lock:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6.0.2
+        with:
+          persist-credentials: false
+      - name: Use default version from uv.lock
+        id: ruff-action
+        uses: ./
+        with:
+          src: __tests__/fixtures/python-project
+          version-file: __tests__/fixtures/uv.lock
+      - name: Correct version gets installed
+        run: |
+          if [ "$RUFF_VERSION" != "0.9.5" ]; then
+            exit 1
+          fi
+        env:
+          RUFF_VERSION: ${{ steps.ruff-action.outputs.ruff-version }}
   test-semver-range:
     runs-on: ubuntu-latest
     steps:
@@ -501,6 +520,7 @@ jobs:
       - test-default-version-from-pyproject-optional-dependencies
       - test-default-version-from-requirements
       - test-default-version-from-requirements-with-hash
+      - test-default-version-from-uv-lock
       - test-semver-range
       - test-pep440-version-specifier
       - test-checksum

README.md

@@ -178,14 +178,14 @@ to install the latest version that satisfies the range.
 #### Install a version from a specified version file
 
 You can specify a file to read the version from.
-Currently `pyproject.toml` and `requirements.txt` are supported. If the file cannot be parsed
-or does not contain a Ruff version, the action warns and falls back to `latest`.
+Currently `pyproject.toml`, `requirements.txt` and `uv.lock` are supported. If the file cannot
+be parsed or does not contain a Ruff version, the action warns and falls back to `latest`.
 
 ```yaml
 - name: Install a version from a specified version file
   uses: astral-sh/ruff-action@v4.0.0
   with:
-    version-file: "my-path/to/pyproject.toml-or-requirements.txt"
+    version-file: "my-path/to/pyproject.toml-requirements.txt-or-uv.lock"
 ```
 
 Version resolution precedence is:

__tests__/fixtures/uv.lock

@@ -0,0 +1,20 @@
+version = 1
+revision = 1
+requires-python = ">=3.11"
+
+[[package]]
+name = "example-project"
+version = "0.1.0"
+source = { editable = "." }
+dependencies = [
+    { name = "ruff" },
+]
+
+[package.metadata]
+requires-dist = [{ name = "ruff", specifier = ">=0.9.0" }]
+
+[[package]]
+name = "ruff"
+version = "0.9.5"
+source = { registry = "https://pypi.org/simple" }
+sdist = { url = "https://files.pythonhosted.org/packages/source/r/ruff/ruff-0.9.5.tar.gz", hash = "sha256:11aecd7a633932875ab3cb05a484c99970b9d52606ce9ea912b690b02653d56c", size = 3634177 }

__tests__/version/file-parser.test.ts

@@ -9,9 +9,11 @@ jest.unstable_mockModule("@actions/core", () => ({
   warning,
 }));
 
-const { findRuffVersionInSpec, getRuffVersionFromFile } = await import(
-  "../../src/version/file-parser"
-);
+const {
+  findRuffVersionInSpec,
+  getRuffVersionFromFile,
+  getRuffVersionFromUvLockContent,
+} = await import("../../src/version/file-parser");
 
 describe("file-parser", () => {
   beforeEach(() => {
@@ -124,5 +126,26 @@ describe("file-parser", () => {
       );
       expect(result).toBe("~0.8.2");
     });
+
+    it("reads the version from uv.lock", () => {
+      const result = getRuffVersionFromFile("__tests__/fixtures/uv.lock");
+      expect(result).toBe("0.9.5");
+    });
+  });
+
+  describe("getRuffVersionFromUvLockContent", () => {
+    it("extracts the ruff version from uv.lock content", () => {
+      const result = getRuffVersionFromUvLockContent(
+        '[[package]]\nname = "other"\nversion = "1.0.0"\n\n[[package]]\nname = "ruff"\nversion = "0.9.5"\n',
+      );
+      expect(result).toBe("0.9.5");
+    });
+
+    it("returns undefined when ruff is not in uv.lock", () => {
+      const result = getRuffVersionFromUvLockContent(
+        '[[package]]\nname = "other"\nversion = "1.0.0"\n',
+      );
+      expect(result).toBeUndefined();
+    });
   });
 });

action.yml

@@ -15,7 +15,7 @@ inputs:
     required: false
     default: ""
   version-file:
-    description: "Path to a pyproject.toml or requirements.txt file to read the version from. If parsing fails, the action warns and falls back to `latest`."
+    description: "Path to a pyproject.toml, requirements.txt or uv.lock file to read the version from. If parsing fails, the action warns and falls back to `latest`."
     required: false
   checksum:
     description: "The checksum of the ruff version to install"

dist/ruff-action/index.cjs

@@ -31702,6 +31702,14 @@ var VERSION_FILE_PARSERS = [
     },
     supports: (filePath) => filePath.endsWith("pyproject.toml")
   },
+  {
+    format: "uv.lock",
+    parse: (filePath) => {
+      const fileContent = import_node_fs2.default.readFileSync(filePath, "utf-8");
+      return getRuffVersionFromUvLockContent(fileContent);
+    },
+    supports: (filePath) => filePath.endsWith("uv.lock")
+  },
   {
     format: "requirements",
     parse: (filePath) => {
@@ -31775,6 +31783,15 @@ function getRuffVersionFromPyprojectContent(pyprojectContent) {
 function parsePyprojectContent(pyprojectContent) {
   return parse2(pyprojectContent);
 }
+function getRuffVersionFromUvLockContent(uvLockContent) {
+  const uvLock = parse(uvLockContent);
+  const ruffPackage = (uvLock.package || []).find((pkg) => pkg.name === "ruff");
+  if (ruffPackage?.version === void 0) {
+    return void 0;
+  }
+  info(`Found ruff version in uv.lock: ${ruffPackage.version}`);
+  return ruffPackage.version;
+}
 function getVersionFileParser(filePath) {
   return VERSION_FILE_PARSERS.find((parser) => parser.supports(filePath));
 }

src/version/file-parser.ts

@@ -24,6 +24,10 @@ interface Pyproject {
   };
 }
 
+interface UvLock {
+  package?: Array<{ name?: string; version?: string }>;
+}
+
 const VERSION_FILE_PARSERS: VersionFileParser[] = [
   {
     format: "pyproject.toml",
@@ -33,6 +37,14 @@ const VERSION_FILE_PARSERS: VersionFileParser[] = [
     },
     supports: (filePath) => filePath.endsWith("pyproject.toml"),
   },
+  {
+    format: "uv.lock",
+    parse: (filePath) => {
+      const fileContent = fs.readFileSync(filePath, "utf-8");
+      return getRuffVersionFromUvLockContent(fileContent);
+    },
+    supports: (filePath) => filePath.endsWith("uv.lock"),
+  },
   {
     format: "requirements",
     parse: (filePath) => {
@@ -132,6 +144,18 @@ export function parsePyprojectContent(pyprojectContent: string): Pyproject {
   return toml.parse(pyprojectContent) as Pyproject;
 }
 
+export function getRuffVersionFromUvLockContent(
+  uvLockContent: string,
+): string | undefined {
+  const uvLock = toml.parse(uvLockContent) as UvLock;
+  const ruffPackage = (uvLock.package || []).find((pkg) => pkg.name === "ruff");
+  if (ruffPackage?.version === undefined) {
+    return undefined;
+  }
+  core.info(`Found ruff version in uv.lock: ${ruffPackage.version}`);
+  return ruffPackage.version;
+}
+
 function getVersionFileParser(filePath: string): VersionFileParser | undefined {
   return VERSION_FILE_PARSERS.find((parser) => parser.supports(filePath));
 }

src/version/types.ts

@@ -4,7 +4,7 @@ export type VersionSource =
   | "pyproject.toml"
   | "default";
 
-export type VersionFileFormat = "pyproject.toml" | "requirements";
+export type VersionFileFormat = "pyproject.toml" | "requirements" | "uv.lock";
 
 export interface ParsedVersionFile {
   format: VersionFileFormat;