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Use * instead of Unpack[...] in messages when targeting Python 3.11 or later #16445
Description
On Python 3.11 and later it seems better to use the native syntax with * instead of Unpack[...] in various messages.
This is the current behavior:
x: tuple[int, *tuple[int, ...]]
# note: Revealed type is "tuple[builtins.int, Unpack[builtins.tuple[builtins.int, ...]]]"
reveal_type(x)I'd expect the note to look like this:
Revealed type is "tuple[builtins.int, *builtins.tuple[builtins.int, ...]]"
Activity
ilevkivskyi commentedon Nov 10, 2023
Yeah, we already do this for error messages, see https://github.com/python/mypy/blob/master/mypy/messages.py#L2519-L2520. I just noticed one tricky thing btw:
Unpackcan be also used forTypedDictunpacking in**kwargs, in that case we need to keep it asUnpack[...].AlexWaygood commentedon Nov 10, 2023
See also python/cpython#104048 and python/typing_extensions#163, where we changed the runtime repr of
Unpackto reflect that it could now be used in a PEP-692 context as well as a PEP-646 contextilevkivskyi commentedon May 16, 2026
On latest version we show
I think this can be closed now.