python / python/mypy

Daemon issues with retargeting re-exported names

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#6,548 2 comments 0 reactions 0 assignees View on GitHub

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bug priority-0-high topic-daemon topic-fine-grained-incremental
Dominant language
Python
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Forks
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Description

Consider the following test:

[case testRetargetReexport]
from m import M

def f(x: M) -> None: ...

f(M())

[file m.py]
from n import M
[file m.py.2]
from q import M

[file n.py]
class M: ...

[file q.py]
class M: ...
[out]
==

The daemon fails in step two with the error
Argument 1 to "f" has incompatible type "q.M"; expected "n.M"

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Research direction

Start with the testRetargetReexport case and its m.py, m.py.2, n.py, and q.py fixtures, then run the daemon test that exercises them. Trace how the daemon retargets the re-exported M name between steps; done means step two produces no incompatible-type error.

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
35/100

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