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reveal_type(x) where x: Tuple[int, ...] doesn't show "..." #9522
Description
Bug Report
Using reveal_type() on a variable whose type is a variable-length tuple shows misleading output.
While it's different from the output for a fixed-length tuple (which shows Tuple[builtins.int]), it doesn't clearly indicate that the type is variable-length.
Note that with PEP 585 accepted, eventually we'll have to use builtins.tuple (or, I'd recomment, plain tuple) for both situations.
To Reproduce
from typing import Tuple
a: Tuple[int, ...]
reveal_type(a)Expected Behavior
t.py:3: note: Revealed type is 'builtins.tuple[builtins.int, ...]'
or
t.py:3: note: Revealed type is 'Tuple[builtins.int, ...]'
Actual Behavior
t.py:3: note: Revealed type is 'builtins.tuple[builtins.int]'
Your Environment
Master or 0.782, no flags.
Activity
hauntsaninja commentedon Oct 2, 2020
It looks like mypy uses builtins.tuple as a homogenous tuple type:
mypy/mypy/typeanal.py
Line 290 in b884a39
Display ellipsis when formatting variadic `tuple[T, ...]` (#11857)
Display ellipsis when formatting variadic `tuple[T, ...]` (python#11857)