Preserve some lost narrowing, cleanup#20674
Merged
hauntsaninja merged 1 commit intopython:masterfrom Jan 29, 2026
Merged
Conversation
hauntsaninja
commented
Jan 28, 2026
| continue | ||
| target_type = operand_types[j] | ||
| if should_coerce_literals: | ||
| # TODO: doing this prevents narrowing a single-member Enum to literal |
Collaborator
Author
There was a problem hiding this comment.
This comment was on the wrong coerce_to_literal call
(In general, it's a very minor thing — there are more important other improvements to be made to narrowing — so I moved this text into the relevant test)
Contributor
|
Diff from mypy_primer, showing the effect of this PR on open source code: static-frame (https://github.com/static-frame/static-frame)
+ static_frame/core/type_blocks.py:1633: error: Unused "type: ignore" comment [unused-ignore]
+ static_frame/core/type_blocks.py:1634: error: Unused "type: ignore" comment [unused-ignore]
+ static_frame/core/type_blocks.py:1759: error: Unused "type: ignore" comment [unused-ignore]
+ static_frame/core/type_blocks.py:1760: error: Unused "type: ignore" comment [unused-ignore]
|
Collaborator
Author
|
static-frame changes are correct |
hauntsaninja
added a commit
to hauntsaninja/mypy
that referenced
this pull request
Jan 29, 2026
I introduced some more instances of python#12320 Noticed while analysing python#20674
JukkaL
approved these changes
Jan 29, 2026
hauntsaninja
added a commit
that referenced
this pull request
Jan 29, 2026
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
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Outdated suggestions cannot be applied.This suggestion has been applied or marked resolved.Suggestions cannot be applied from pending reviews.Suggestions cannot be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.
#20660 is proving a little tricky, so I'm going to try and land some of the diff independently.
I think of this as mostly a cleanup PR, but it does change a few semantics. In particular, the places where we previously added a
{}to the list of type maps used to clobber some narrowing