possibly-undefined false negative for variable annotation
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Nobody has claimed this yet.
bug
topic-possibly-undefined
- Dominant language
- Python
- Stars
- 20.6k
- Forks
- 3.3k
- PR merge metrics
- PR metrics pending
Description
Reported by KotlinIsland in #16609
# mypy: enable-error-code="possibly-undefined"
def foo() -> None:
a: int
print(a)
https://mypy-play.net/?mypy=latest&python=3.12&gist=a044519fd87d51e6028a236f02bcb9cb
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
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- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Reproduce the annotated-local example in the linked mypy-play case with possibly-undefined enabled, then trace the checker path that handles variable annotations and undefined-use analysis. Done means the example reports that a may be undefined at print(a), with a regression test covering this case.
Written by the indexing model from the issue text.
Assessment
- Tech stack
- python
- Domain
- devtools
- Issue type
- Bug
- Difficulty
- 3/5
- Estimated time
- 1-2 days
- Activity status
- Stale
- Clarity
- Mostly clear
- Newbie friendliness
- 45/100