Empty coverage reports for Python 3.10.15 and 3.10.16

[keesvanhespen]

🐞 bug report

Affected Rule

rules_python

Is this a regression?

No

Description

Running bazel coverage does not produce coverage reports for all versions of Python. The coverage.dat files are empty when using Python version 3.10.15 and 3.10.16. Other versions of Python 3.10 do seem to produce valid coverage reports.

I did not test Python 3.11 or 3.12.

🔬 Minimal Reproduction

I added tests on a fork of main: python-3-10-16-coverage.

Running

bazel coverage --action_env=COVERAGE_GCOV_OPTIONS=-b --combined_report=lcov --strategy=CoverageReport=local -- //test_code/...

from the tests/coverage directory returns a filled coverage.dat file in bazel-out for Python 3.10.14, but it is empty for 3.10.16.

🌍 Your Environment

Operating System:

  
   MacOS Sequoia ARM 64
  

Output of bazel version:

  
Aspect CLI version: 2025.06.52+25667cae2
INFO: Invocation ID: 58fd115a-8c31-42c8-a32f-e11056aa355a
Build label: 8.2.1
Build target: @@//src/main/java/com/google/devtools/build/lib/bazel:BazelServer
Build time: Thu Apr 17 18:31:45 2025 (1744914705)
Build timestamp: 1744914705
Build timestamp as int: 1744914705
  

Rules_python version:

  
 1.3.0
  

Anything else relevant?

[aignas]

Thanks for reporting this. I added help wanted as I would love more eyes on this helping debugging.