Testing: Add isort-only Ruff to pre-commit and autotest; #6538

Adding Ruff to both the pre-commit script
(with --fix passed, thus sorting imports automatically)
and to GH autotest (checking only).
Ruff is currently only configured to check for import sorting.
Other linting functions (flake8, pyupgrade) will be added progressively.

.github/workflows/autotest.yml

@@ -20,6 +20,20 @@ jobs:
         shell: bash
         run: |
           python3 tools/add_header --dry-run --disable-progress-bar
+  python_ruff:
+    runs-on: ubuntu-latest
+    steps:
+      - uses: actions/checkout@v4
+      - name: Install Python
+        uses: actions/setup-python@v5
+        with:
+          python-version: "3.11"
+      - name: Install dependencies
+        run: |
+          python -m pip install --upgrade pip
+          pip install ruff
+      - name: Run Ruff
+        run: ruff check --output-format=github .
   python_annotations:
     if: |
       !startsWith(github.ref_name, 'release')

.pre-commit-config.yaml

@@ -15,3 +15,8 @@ repos:
     description: Run the `add_header` script to verify the file headers
     entry: tools/add_header
     language: system
+- repo: https://github.com/astral-sh/ruff-pre-commit
+  rev: v0.3.3
+  hooks:
+    - id: ruff
+      args: [ --fix ]

pyproject.toml

@@ -1,3 +1,49 @@
 [build-system]
 requires = ["setuptools", "wheel"]
 build-backend = "setuptools.build_meta"
+
+[tool.ruff]
+line-length = 256
+
+# Exclude a variety of commonly ignored directories.
+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",
+    "build",
+    "dist",
+    "node_modules",
+    "site-packages",
+    "venv",
+]
+
+[tool.ruff.lint]
+select = [
+    "I", # isort
+]
+
+ignore = [
+    "ALL",
+    "UP031", # Use format specifiers instead of percent format
+    "SIM210", 
+]
+
+extend-safe-fixes = ["I001"]