fix: guard AutoInterrupt terminate during interpreter shutdown#2105

lweyrich1

On Windows during interpreter shutdown, process objects can be partially torn down and terminate() may raise AttributeError (e.g. missing TerminateProcess).

This PR treats that similarly to the existing OSError handling in _AutoInterrupt._terminate() and adds a regression test covering the AttributeError case.

Tests: pytest -q test/test_autointerrupt.py

Byron

Thanks a lot for the fix, looks good to me!

I will merge once CI is fixed.

EliahKagan

I've made two changes:

Rebased this onto main after merging #2108 to fix #2107 (which arose more recently than #2105 (review) and is not due to changes here, but would have appeared here next time CI ran).
Fixed the blocker mentioned in #2105 (review) where the lint job failed. This was due to an unnecessary import pytest (since the module does not use anything from the pytest module in its own code).

I plan to merge this once CI passes.

Copilot

Pull request overview

Fixes a Windows interpreter-shutdown edge case where Git.AutoInterrupt._terminate() can raise AttributeError from subprocess.Popen.terminate() due to partially torn-down stdlib internals, preventing noisy “Exception ignored in: del” messages.

Changes:

Treat AttributeError from proc.terminate() similarly to existing OSError handling in _AutoInterrupt._terminate().
Add a regression test that simulates terminate() raising AttributeError and asserts _terminate() does not raise and clears proc.

Reviewed changes

Copilot reviewed 2 out of 2 changed files in this pull request and generated 1 comment.

File Description

git/cmd.py	Extends _AutoInterrupt._terminate() exception handling to include AttributeError during termination.
test/test_autointerrupt.py	Adds a focused regression test for AttributeError raised from terminate().

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Catching AttributeError unconditionally here can mask real runtime failures when _terminate() is called outside interpreter shutdown (e.g. the kill_after_timeout path in handle_process_output). Consider only suppressing AttributeError during interpreter finalization (e.g. getattr(sys, "is_finalizing", lambda: False)()), and otherwise re-raising so unexpected terminate/wait breakages don’t silently leave processes running. Also, the comment says “silently ignore” but this logs at INFO—either adjust the wording or log level to match intent.

Suggested change

      
                        # to silently ignore to avoid noisy "Exception ignored in: __del__" messages.
          
                        # to log and ignore to avoid noisy "Exception ignored in: __del__" messages.
          
                        if isinstance(ex, AttributeError) and not getattr(sys, "is_finalizing", lambda: False)():
          
                            # Outside interpreter finalization, an AttributeError here likely indicates
          
                            # a real problem (e.g. broken subprocess internals), so re-raise it instead
          
                            # of silently leaving the process running.
          
                            raise

There may be some merit to this concern, but I don't think it needs to block the change here, since AttributeError really should not arise here in any other way. I'm also not entirely sure that a change along the lines of what the model suggests here would be robust enough to be worth doing. But probably some future change to make this more robust, or do log in more detail when the capability to do so is present, or both, could be worthwhile. (I reiterate that I don't consider this blocking.)

EliahKagan

Thanks @lweyrich1!

Byron approved these changes Feb 26, 2026

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EliahKagan mentioned this pull request Mar 9, 2026

Switch back from Alpine to Debian for WSL #2108

Merged

lweyrich1 and others added 2 commits March 9, 2026 13:47

fix: ignore AutoInterrupt terminate errors during shutdown

3cfd229

Remove unnecessary pytest import in a test module

357aad1

EliahKagan force-pushed the fix-autointerrupt-shutdown-guard branch from dae9b25 to 357aad1 Compare March 9, 2026 17:56

EliahKagan approved these changes Mar 9, 2026

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EliahKagan requested a review from Copilot March 9, 2026 18:03

Copilot started reviewing on behalf of EliahKagan March 9, 2026 18:03 View session

Copilot AI reviewed Mar 9, 2026

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+                          # On interpreter shutdown (notably on Windows), parts of the stdlib used by
+                          # subprocess can already be torn down (e.g. `subprocess._winapi` becomes None),
+                          # which can cause AttributeError during terminate(). In that case, we prefer
+                          # to silently ignore to avoid noisy "Exception ignored in: __del__" messages.

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fix: guard AutoInterrupt terminate during interpreter shutdown#2105