Harden GitHub Actions workflows with zizmor

.github/dependabot.yml

@@ -5,6 +5,8 @@ updates:
     directory: "/"
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7
     groups:
       github-actions:
         patterns:
@@ -13,3 +15,5 @@ updates:
     directory: "/"
     schedule:
       interval: "weekly"
+    cooldown:
+      default-days: 7

.github/workflows/main.yml

@@ -15,27 +15,35 @@ on:
     - '*'
   merge_group:
 
+permissions: {}
+
 jobs:
 
   run-type-checking:
 
     name: Run tests for type-checking
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
 
     steps:
-      - uses: actions/checkout@v6
-      - uses: astral-sh/setup-uv@v7
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        with:
+          persist-credentials: false
+      - uses: astral-sh/setup-uv@37802adc94f370d6bfd71619e3f0bf239e1f3b78 # v7
         with:
           enable-cache: true
       - name: Install just
-        uses: extractions/setup-just@v3
+        uses: extractions/setup-just@f8a3cce218d9f83db3a2ecd90e41ac3de6cdfd9b # v3
       - name: Run type checking
         run: just typing
 
   run-tests:
 
     name: Run tests for ${{ matrix.os }} on ${{ matrix.python-version }}
     runs-on: ${{ matrix.os }}
+    permissions:
+      contents: read
 
     strategy:
       fail-fast: false
@@ -44,15 +52,17 @@ jobs:
         python-version: ['3.10', '3.11', '3.12', '3.13', '3.14']
 
     steps:
-      - uses: actions/checkout@v6
-      - uses: astral-sh/setup-uv@v7
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        with:
+          persist-credentials: false
+      - uses: astral-sh/setup-uv@37802adc94f370d6bfd71619e3f0bf239e1f3b78 # v7
         with:
           python-version: ${{ matrix.python-version }}
           enable-cache: true
       - name: Install just
-        uses: extractions/setup-just@v3
+        uses: extractions/setup-just@f8a3cce218d9f83db3a2ecd90e41ac3de6cdfd9b # v3
       - name: Run tests
         run: just test
 
       - name: Upload test coverage reports to Codecov with GitHub Action
-        uses: codecov/codecov-action@v5
+        uses: codecov/codecov-action@75cd11691c0faa626561e295848008c8a7dddffe # v5

.github/workflows/publish-to-pypi.yml

@@ -2,15 +2,21 @@ name: Publish Python 🐍 distribution 📦 to PyPI
 
 on: push
 
+permissions: {}
+
 jobs:
   build:
     name: Build distribution 📦
     runs-on: ubuntu-latest
+    permissions:
+      contents: read
 
     steps:
-    - uses: actions/checkout@v6
+    - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+      with:
+        persist-credentials: false
     - name: Set up Python
-      uses: actions/setup-python@v6
+      uses: actions/setup-python@a309ff8b426b58ec0e2a45f0f869d46889d02405 # v6
       with:
         python-version: "3.x"
     - name: Install pypa/build
@@ -22,7 +28,7 @@ jobs:
     - name: Build a binary wheel and a source tarball
       run: python3 -m build
     - name: Store the distribution packages
-      uses: actions/upload-artifact@v7
+      uses: actions/upload-artifact@bbbca2ddaa5d8feaa63e36b76fdaad77386f024f # v7
       with:
         name: python-package-distributions
         path: dist/
@@ -41,12 +47,12 @@ jobs:
 
     steps:
     - name: Download all the dists
-      uses: actions/download-artifact@v8
+      uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8
       with:
         name: python-package-distributions
         path: dist/
     - name: Publish distribution 📦 to PyPI
-      uses: pypa/gh-action-pypi-publish@release/v1
+      uses: pypa/gh-action-pypi-publish@ed0c53931b1dc9bd32cbe73a98c7f6766f8a527e # release/v1
 
   github-release:
     name: >-
@@ -62,30 +68,32 @@ jobs:
 
     steps:
     - name: Download all the dists
-      uses: actions/download-artifact@v8
+      uses: actions/download-artifact@3e5f45b2cfb9172054b4087a40e8e0b5a5461e7c # v8
       with:
         name: python-package-distributions
         path: dist/
     - name: Sign the dists with Sigstore
-      uses: sigstore/gh-action-sigstore-python@v3.2.0
+      uses: sigstore/gh-action-sigstore-python@a5caf349bc536fbef3668a10ed7f5cd309a4b53d # v3.2.0
       with:
         inputs: >-
           ./dist/*.tar.gz
           ./dist/*.whl
     - name: Create GitHub Release
       env:
         GITHUB_TOKEN: ${{ github.token }}
+        RELEASE_TAG: ${{ github.ref_name }}
+        REPOSITORY: ${{ github.repository }}
       run: >-
         gh release create
-        '${{ github.ref_name }}'
-        --repo '${{ github.repository }}'
+        "$RELEASE_TAG"
+        --repo "$REPOSITORY"
         --notes ""
     - name: Upload artifact signatures to GitHub Release
       env:
         GITHUB_TOKEN: ${{ github.token }}
-      # Upload to GitHub Release using the `gh` CLI. `dist/` contains the built
-      # packages, and the sigstore-produced signatures and certificates.
+        RELEASE_TAG: ${{ github.ref_name }}
+        REPOSITORY: ${{ github.repository }}
       run: >-
         gh release upload
-        '${{ github.ref_name }}' dist/**
-        --repo '${{ github.repository }}'
+        "$RELEASE_TAG" dist/**
+        --repo "$REPOSITORY"

.github/workflows/zizmor.yml

@@ -0,0 +1,48 @@
+name: zizmor
+
+on:
+  push:
+    branches:
+    - main
+  pull_request:
+    branches:
+    - '*'
+  schedule:
+    - cron: '0 7 * * 1'
+  workflow_dispatch:
+
+permissions: {}
+
+jobs:
+  zizmor:
+    name: Scan GitHub Actions
+    runs-on: ubuntu-latest
+    permissions:
+      contents: read
+      security-events: write
+
+    steps:
+      - uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v6
+        with:
+          persist-credentials: false
+
+      - uses: astral-sh/setup-uv@37802adc94f370d6bfd71619e3f0bf239e1f3b78 # v7
+        with:
+          enable-cache: true
+          python-version: '3.13'
+
+      - name: Run zizmor
+        run: uvx --from zizmor zizmor --format=github .
+
+      - name: Generate SARIF report
+        if: always()
+        run: uvx --from zizmor zizmor --format=sarif --no-exit-codes . > zizmor.sarif
+
+      - name: Upload SARIF report
+        if: >
+          always() &&
+          (github.event_name != 'pull_request' ||
+          github.event.pull_request.head.repo.full_name == github.repository)
+        uses: github/codeql-action/upload-sarif@c10b8064de6f491fea524254123dbe5e09572f13 # v4
+        with:
+          sarif_file: zizmor.sarif

src/pytask_parallel/config.py

@@ -27,7 +27,8 @@ def pytask_parse_config(config: dict[str, Any]) -> None:
         raise ValueError(msg) from None
 
     if config["n_workers"] == "auto":
-        config["n_workers"] = max(os.cpu_count() - 1, 1)  # type: ignore[operator]
+        cpu_count = os.cpu_count() or 1
+        config["n_workers"] = max(cpu_count - 1, 1)
 
     # If more than one worker is used, and no backend is set, use loky.
     if config["n_workers"] > 1 and config["parallel_backend"] == ParallelBackend.NONE:

src/pytask_parallel/execute.py

@@ -137,7 +137,7 @@ def pytask_execute_build(session: Session) -> bool | None:  # noqa: C901, PLR091
                             newly_collected_reports.append(
                                 ExecutionReport.from_task_and_exception(
                                     task,
-                                    wrapper_result.exc_info,  # type: ignore[arg-type]
+                                    cast("Any", wrapper_result.exc_info),
                                 )
                             )
                             running_tasks.pop(task_name)
@@ -213,7 +213,7 @@ def pytask_execute_task(session: Session, task: PTask) -> Future[WrapperResult]:
         # cloudpickle will pickle it with the function. See cloudpickle#417, pytask#373
         # and pytask#374.
         task_module = get_module(task.function, getattr(task, "path", None))
-        if should_pickle_module_by_value(task_module):
+        if task_module is not None and should_pickle_module_by_value(task_module):
             cloudpickle.register_pickle_by_value(task_module)
 
         return cast("Any", wrapper_func).submit(
@@ -237,7 +237,7 @@ def pytask_execute_task(session: Session, task: PTask) -> Future[WrapperResult]:
         # cloudpickle will pickle it with the function. See cloudpickle#417, pytask#373
         # and pytask#374.
         task_module = get_module(task.function, getattr(task, "path", None))
-        if should_pickle_module_by_value(task_module):
+        if task_module is not None and should_pickle_module_by_value(task_module):
             cloudpickle.register_pickle_by_value(task_module)
 
         return session.config["_parallel_executor"].submit(

src/pytask_parallel/utils.py

@@ -136,7 +136,7 @@ def _parse_future_exception(
     return None if exc is None else (type(exc), exc, exc.__traceback__)
 
 
-def get_module(func: Callable[..., Any], path: Path | None) -> ModuleType:
+def get_module(func: Callable[..., Any], path: Path | None) -> ModuleType | None:
     """Get the module of a python function.
 
     ``functools.partial`` obfuscates the module of the function and
@@ -151,8 +151,8 @@ def get_module(func: Callable[..., Any], path: Path | None) -> ModuleType:
         func = func.func
 
     if path:
-        return inspect.getmodule(func, path.as_posix())  # type: ignore[return-value]
-    return inspect.getmodule(func)  # type: ignore[return-value]
+        return inspect.getmodule(func, path.as_posix())
+    return inspect.getmodule(func)
 
 
 def strip_annotation_locals(task: PTask) -> None:

src/pytask_parallel/wrappers.py

@@ -138,7 +138,11 @@ def wrap_task_in_process(  # noqa: PLR0913
         except Exception:  # noqa: BLE001
             exc_info = sys.exc_info()
             processed_exc_info = _render_traceback_to_string(
-                exc_info,  # type: ignore[arg-type]
+                (
+                    cast("type[BaseException]", exc_info[0]),
+                    cast("BaseException", exc_info[1]),
+                    exc_info[2],
+                ),
                 show_locals,
                 console_options,
             )