`TYPE_CHECKING` doesn't work if imported with alias
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bug
- Dominant language
- Python
- Stars
- 20.6k
- Forks
- 3.3k
- PR merge metrics
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Description
from typing import TYPE_CHECKING
from typing import TYPE_CHECKING as amogus
if not TYPE_CHECKING:
1 + "" # no error (unreachable)
if not amogus:
1 + "" # error
Contributor guide
First steps
- Read the whole issue, then the project's contributing guide.
- Comment on the issue to say you are picking it up — it saves two people doing the same work.
- Fork the repository and make your change on a branch.
- Open a pull request that references the issue number.
Research direction
Start by reproducing the discrepancy in the issue's Python snippet or linked mypy playground, then trace how mypy recognizes TYPE_CHECKING imports and aliases. Done means an aliased import behaves like the direct import for unreachable-code analysis, with regression coverage for both forms.
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
- Clearly specified
- Newbie friendliness
- 42/100