Fix CI failure with tox 4.56 by setting skip_missing_interpreters = true#1033
Merged
Conversation
tox 4.56.0 changed the default of skip_missing_interpreters back to false (tox-dev/tox#3966). The CI build matrix installs only one Python version per runner and runs plain tox, so environments for missing interpreters now fail instead of being skipped. Restore the previous behavior explicitly in tox.ini.
Both python_version branches pinned the same tox version, so the environment markers no longer serve any purpose.
mokuzon
changed the title
Yang-33
approved these changes
Jul 13, 2026
| @@ -1,4 +1,8 @@ | |||
| [tox] | |||
| # tox 4.56.0 changed the default of skip_missing_interpreters back to false | |||
Contributor
There was a problem hiding this comment.
history is not requried as inline comment, so we can remove the first sentence? CI runners... is much enough.
Contributor
Author
There was a problem hiding this comment.
It was automatically merged.
I'll delete it the next time I edit this.
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.This suggestion is invalid because no changes were made to the code.Suggestions cannot be applied while the pull request is closed.Suggestions cannot be applied while viewing a subset of changes.Only one suggestion per line can be applied in a batch.Add this suggestion to a batch that can be applied as a single commit.Applying suggestions on deleted lines is not supported.You must change the existing code in this line in order to create a valid suggestion.Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be applied on multi-line comments.Suggestions cannot be applied while the pull request is queued to merge.Suggestion cannot be applied right now. Please check back later.
Summary
Supersedes #1026 (Renovate update of tox 4.55.1 -> 4.56.1), whose CI is failing.
tox 4.56.0 changed the default of
skip_missing_interpretersback tofalse(tox-dev/tox#3966).The
buildjob in.github/workflows/auto-testing.ymlis a matrix where each runner installs only a single Python version and then runs plaintox, so all envs for interpreters not installed on that runner (e.g.py3.10on the 3.11 runner) now fail with "could not find python interpreter" instead of being skipped.This PR adds
skip_missing_interpreters = trueto the[tox]section oftox.inito restore the previous behavior.