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Add PowerShell scripts to help debug test_stdio_context_manager_exiting flakiness on Windows with Python 3.11/3.12: - check-tee-command.ps1: Verify tee command availability - test-stdio-flakiness-200-runs.ps1: Run test 200 times for statistics - test-stdio-flakiness-until-failure.ps1: Run until failure occurs - test-stdio-verbose-debug.ps1: Single run with maximum debug output - README.md: Documentation for using the scripts
Add -n 0 flag to disable xdist parallel execution which was causing test collection failures. Also fix successful run count calculation.
- Use PYTEST_DISABLE_PLUGIN_AUTOLOAD environment variable (recommended in CLAUDE.md) - Use -p no:xdist flag to explicitly disable the plugin - Add --no-cov to avoid coverage plugin issues - Add test-stdio-simple.ps1 to try different methods of disabling xdist
- Add setup-environment.ps1 to configure Git for Windows tee in PATH - Simplify all scripts to use working -o addopts="" approach - Add tee availability checks to all scripts - Update README with clear setup instructions and troubleshooting - Remove complex xdist workarounds in favor of simple override
Based on deep analysis, the flakiness likely occurs due to: 1. Job Object handle race conditions when tests run in parallel 2. Windows handle inheritance between test processes 3. Timing sensitivity in the minimal test that just opens/closes immediately 4. Python 3.11/3.12 specific subprocess handling changes These scripts help reproduce the CI environment conditions: - test-stdio-parallel-flakiness.ps1: Runs with xdist parallel workers - test-stdio-stress-race.ps1: Rapidly creates processes to expose races
This script collects detailed information about: - Windows version and build - Python version and subprocess configuration - Job Objects support - Security software - Process creation timing - Handle inheritance settings This will help identify differences between local dev environments (where the test passes) and CI environments (where it flakes).
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