Failure to resolve a specific import structure

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#4,144 5 comments 0 reactions 0 assignees View on GitHub

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Assessment

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

Research direction

Recreate the package using top/init.py, top/b/init.py, top/b/_b.py, and top/c.py, then run mypy -m top to observe the unresolved b.Cls error. Trace how the import resolver handles the re-export from top.b while top is being initialized. Done means this example resolves b.Cls without the reported error, with relevant tests added or updated.

Written by the indexing model from the issue text.

Description

bug priority-2-low topic-import-cycles

Given the following module structure:

top
|-- __init__.py
|-- b
|   |-- __init__.py
|   `-- _b.py
`-- c.py

And the following module contents:

  • top/__init__.py:
from .b import *
from .c import *
  • top/b/__init__.py:
from ._b import *
  • top/b/_b.py:
import top
class Cls:
    pass
  • top/c.py:
from . import b
foo: b.Cls = None

mypy -m top fails to resolve b.Cls:

top/c.py:2: error: Name 'b.Cls' is not defined

Dominant language
Python
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Merged PRs (30d)
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