Description
Describe the bug
pyright should support type narrowing based on tuple length to avoid the false positive in the following code snippet:
from typing import Union
MultiTuple = Union[tuple[object], tuple[object, object]]
def process_tuples(tup: MultiTuple) -> object:
if len(tup) == 1:
return tup[0]
else:
first, second = tup
return second /home/gregory/Downloads/testcase/pytest/tuplesize.py:9:9 - error: Tuple size mismatch: expected 2 but received 1 (reportGeneralTypeIssues)This came up in the rich codebase, and there's a corresponding mypy issue with an open PR: python/mypy#1178
Expected behavior
pyright should be able to type narrow tuples based on len()
VS Code extension or command-line
pyright 1.1.180 Linux commandline