[Python] PyCharm Debugger Stuck on "Collecting data..." When Debugging Pytest Unit Test

I'm encountering a persistent issue with PyCharm when trying to debug a pytest unit test.

What works:

• Running the project normally and attaching the debugger works fine.
• Debugging regular scripts behaves as expected.

What doesn't work:

• When I debug a pytest unit test:
  • The debugger halts at the first breakpoint.
  • It shows "Collecting data..." instead of displaying variable values.
  • Clicking "Step Over" or "Continue" does nothing — the debugger appears frozen.

Environment:

• PyCharm version: 2025.2.0.1
• Python version: 3.12.11
• OS: macOS
• Venv Manager: uv
• pytest version: 8.4.0

What I've tried:

• Restarting PyCharm and invalidating caches.
• Simplifying __str__ and __repr__ methods in my code.
• Enabling Gevent compatible mode in the debugger settings — no improvement.
• Verified that --cov is not present in my pytest.ini.
• Tried adding --no-cov to the Additional Arguments in the Run/Debug Configuration, but this caused an error:
  unrecognized arguments: --no-cov

Question:


Has anyone found a reliable fix for this issue? Is there a workaround to get PyCharm's debugger working properly with pytest?

Any help would be greatly appreciated!

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