python / python/mypy

`no-redef` issued with package import but not with local import

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bug
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Python
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Description

Bug Report

I can type-annotate untyped imports from a local file, but not from a package (in which case I get a no-redef error).

To Reproduce

my_local.py

from funcy.decorators import decorator

@decorator
def retry(call, tries, errors=Exception, timeout=0, filter_errors=None):
    pass

bug.py

from typing import Callable

# Works without error message
r1: Callable
from my_local import retry as r1

# pip install funcy
# Throws a no-redef error
r2: Callable
from funcy.flow import retry as r2

Expected Behavior

Same behavior (no error) in both cases.

Actual Behavior

my_local.py:1: error: Skipping analyzing "funcy.decorators": module is installed, but missing library stubs or py.typed marker  [import]
my_local.py:5: error: Function is missing a type annotation  [no-untyped-def]
bug.py:4: error: Missing type parameters for generic type "Callable"  [type-arg]
bug.py:9: error: Missing type parameters for generic type "Callable"  [type-arg]
bug.py:10: error: Skipping analyzing "funcy.flow": module is installed, but missing library stubs or py.typed marker  [import]
bug.py:10: note: See https://mypy.readthedocs.io/en/stable/running_mypy.html#missing-imports
bug.py:10: error: Name "r2" already defined on line 9  [no-redef]
Found 6 errors in 2 files (checked 1 source file)

Your Environment

  • Mypy version used: mypy 1.2.0 (compiled: yes)
  • Mypy command-line flags: none
  • Mypy configuration options from mypy.ini (and other config files): none
  • Python version used: 3.11.2

Somewhat related: https://github.com/python/mypy/issues/13914

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First steps

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  2. Comment on the issue to say you are picking it up — it saves two people doing the same work.
  3. Fork the repository and make your change on a branch.
  4. Open a pull request that references the issue number.

Research direction

Reproduce the diagnostics using my_local.py and bug.py with the reported mypy and Python versions, then compare the local and package import paths. Trace how the two imports are analyzed and identify why only the package case produces no-redef; done means both examples behave consistently without that error.

Written by the indexing model from the issue text.

Assessment

Tech stack
python
Domain
devtools
Issue type
Bug
Difficulty
4/5
Estimated time
3-5 days
Activity status
Stale
Clarity
Mostly clear
Newbie friendliness
35/100

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