`type[T]` is not `() -> T`
Open
Nobody has claimed this yet.
bug
- Dominant language
- Python
- Stars
- 20.6k
- Forks
- 3.3k
- PR merge metrics
- PR metrics pending
Description
from typing import TypeVar, Callable
T = TypeVar("T")
class A:
def __init__(self, a: int) -> None:
...
def foo(t: type[T]) -> T:
return t()
foo(A) # SUS ALERT!
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.
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- Open a pull request that references the issue number.
Research direction
Start by reproducing the reported Python snippet with type[T], class A, and foo; inspect how the type checker models calling a type[T]. Done means the checker reports that foo(A) is invalid because A requires an argument, rather than treating type[T] as a zero-argument callable.
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
- 42/100