Ned Batchelder
Can you help me test a change to how coverage․py is packaged? It will take five minutes:
https://gist.github.com/nedbat/9b63b040cddd4778447cce21062d0843
repro.md

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Nov 30 at 9:45pmWeb
Show threadStylus2d ago

@nedbat I ignored all your instructions but I'll report a result anyway.

I have an existing project (wwvbpy) last tested at coverage.py 7.10.3 for 100% branch coverage; it relies on coverage=subprocess (and you've fixed some sharp edges in this area for me previously!).

with coverage.py v7.12.1b1, it still sees 100% branch coverage.

linux (debian trixie) running python 3.13 via uv (uv run --with coverage==7.12.1b1 --with-requirements requirements.txt --python 3.13 make coverage)

Show threadTin Tvrtković2d ago

@nedbat Here we go: https://github.com/python-attrs/cattrs/pull/700

Hm, I thought I had 100% coverage. Need to check whether this is coverage.py or me.

Upgrade coverage by Tinche · Pull Request #700 · python-attrs/cattrs

GitHub
Show threadTin Tvrtković2d ago
@nedbat The missing line is tested using a Hypothesis property-based test, so it's technically possible no tests hit it, but very unlikely. Going to rerun the test suite now.
Show threadJesus Michał "Le Sigh" 🏔 (he)2d ago
@nedbat, Gentoo system install gives 100% for PyPy3.11 7.3.20, CPython 3.12.12 and 3.14.0. I guess that is a good coverage :-).
Show threadHugo van Kemenade2d ago

@nedbat

100%
macOS 15
Python 3.14.0
uv pip install --system coverage==7.12.1b1

83%
macOS 15
Python 3.15.0a2
python3.15 -m pip install coverage==7.12.1b1

Show threadNed Batchelder2d ago
@hugovk Hmm, that's concerning. If you change "python3" to "sys.executable", is 3.15 better?
Show threadAlyssa Coghlan2d ago
@nedbat Is the invocation of "python" rather than "sys.executable" in the gist part of the intended test? (it won't make a difference in an activated venv, but could run a different Python without coverage installed when `PATH` hasn't been adjusted)
Show threadNed Batchelder2d ago
@ancoghlan excellent question! sys.executable would have been better.
Show threadEric Matthes2d ago

@nedbat

macOS 15.7.1
Tested on Python 3.10-3.15
Installed Python with uv
Tested in active venvs
`uv pip install coverage==7.12.1b1`

Python 3.10-3.14: 100%
Python 3.15.0a1: 83%