Add Ruff linter support for stub quality checking with flake8-pyi rules

[Copilot]

Adding Ruff Linter Support to Stubs Quality Checks ✅

Issue: Check stubs with additional linters - specifically ruff
Status: COMPLETE

Implementation Summary

Successfully integrated Ruff as a third linter for MicroPython stubs quality checking, alongside Pyright and MyPy.

Completed Tasks

• Explore repository structure and understand existing linting setup
• Add ruff as a test dependency (pyproject.toml, requirements-test.txt)
• Create typecheck_ruff.py module following the pattern of typecheck_mypy.py
• Integrate ruff into typecheck.py infrastructure
• Update test_snippets.py to include ruff in linter parametrization
• Create test_ruff.py for dedicated ruff testing
• Create feat_ruff test directory with sample files
• Configure ruff to ignore common test snippet patterns (E402, etc.)
• Update _configs/pyproject.toml with ruff configuration
• Enable flake8-pyi (PYI) rules for stub-specific linting
• Configure appropriate ignores for MicroPython stub characteristics
• Verify ruff works on actual stub files (micropython-preview-docstubs passes)
• Create comprehensive documentation (docs/29_ruff.md)
• Add ruff badge to README
• Update documentation index
• Create integration summary (RUFF_INTEGRATION.md)
• Fix CI error by adding requests to requirements-test.txt

Key Features

✨ Fast linting: 10-100x faster than traditional linters
✨ Stub-aware: Built-in flake8-pyi rules for .pyi files
✨ Configured: Proper ignores for MicroPython stub characteristics
✨ Integrated: Works seamlessly with existing pyright/mypy infrastructure
✨ Documented: Complete usage guide and configuration examples

Files Changed

• pyproject.toml (dependencies + configuration)
• requirements-test.txt (dependencies + requests fix)
• tests/quality_tests/typecheck_ruff.py (NEW)
• tests/quality_tests/typecheck.py (ruff support)
• tests/quality_tests/test_ruff.py (NEW)
• tests/quality_tests/test_snippets.py (ruff in parametrization)
• tests/quality_tests/_configs/pyproject.toml (ruff config)
• tests/quality_tests/feat_ruff/ (NEW test directory)
• docs/29_ruff.md (NEW documentation)
• docs/index.md (updated TOC)
• README.md (ruff badge)
• RUFF_INTEGRATION.md (NEW summary)

Testing Results

✅ Ruff module imports successfully
✅ Runs on test directories without errors
✅ Validates stub files correctly (micropython-preview-docstubs passes)
✅ Configuration properly ignores MicroPython-specific patterns
✅ CI error fixed - requests module now in requirements-test.txt

Original prompt

---

This section details on the original issue you should resolve

<issue_title>Check stubs with additional linters </issue_title>
<issue_description>- [ ] flake8-py

• pylint
• ruff ?

</issue_description>

Comments on the Issue (you are @copilot in this section)

@Josverl Lets start adding ruff as that is frequently used.

Fixes #746

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[Josverl]

@copilot
I see that one of the actions that runs the rest and the comparison has an error.

ModuleNotFoundError: No module named 'requests'

https://github.com/Josverl/micropython-stubs/actions/runs/18578590215/job/52969579062

Can you also fix that

[Copilot]

@copilot
I see that one of the actions that runs the rest and the comparison has an error.
...

Fixed in commit d52ac09 - added requests to requirements-test.txt. The module was already in pyproject.toml but was missing from the requirements file used by the CI workflow.

[Josverl]

@copilot