Incorrect handling of methods whose name shadows an existing name

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#4,146 2 comments 1 reaction 0 assignees View on GitHub

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Assessment

Difficulty
3/5
Estimated time
1-2 days
Newbie friendliness
48/100
Issue type
Bug
Clarity
Clearly specified
Activity status
Stale
Tech stack
python
Domain
devtools

Research direction

Reproduce the failure with top/init.py and top/bar.py by running mypy -m top. Trace name resolution for the method annotation where Foo.bar shadows the imported bar module. Done means the example no longer reports Invalid type "top.Foo.bar", while the module-qualified annotation remains valid.

Written by the indexing model from the issue text.

Description

Given the following module structure:

top
|-- __init__.py
`-- bar.py

And the following module contents:

  • top/__init__.py:
from . import bar

class Foo:
    def bar(arg: bar.Spam):
        pass
  • top/bar.py:
class Spam:
    pass

mypy -m top fails:

top/__init__.py:4: error: Invalid type "top.Foo.bar"

This is because it prematurely assumes that bar is a function, not a module.
Interestingly, regular functions do not exhibit this behaviour. The following works fine:

from . import bar

def bar(arg: bar.Spam):
    pass
Dominant language
Python
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