Bug Report
Unpacking a list into multiple variables when the list itself is (partially) created by unpacking another iterable the type inference is faulty
To Reproduce
from typing import reveal_type
text = "some\nstuff"
version, desc, *_ = [*text.split(sep="\n", maxsplit=1), None, None]
reveal_type(version) # str
reveal_type(desc) # None
Expected Behavior
Mypy infers version and desc and str | None (if you want to go very far you can even infer version as str because str.split never returns an empty list, but that is not my expectation)
Actual Behavior
Mypy infers version as str and desc as None
Your Environment
Mypy playground: https://mypy-play.net/?mypy=latest&python=3.12&flags=strict%2Cstrict-bytes%2Ccheck-untyped-defs%2Cdisallow-any-decorated%2Cdisallow-any-expr%2Cdisallow-any-explicit%2Cdisallow-any-generics%2Cdisallow-any-unimported%2Cdisallow-incomplete-defs%2Cdisallow-subclassing-any%2Cdisallow-untyped-calls%2Cdisallow-untyped-decorators%2Cdisallow-untyped-defs%2Cno-implicit-reexport%2Cno-strict-optional%2Cstrict-equality%2Cstrict-equality-for-none%2Cwarn-incomplete-stub%2Cwarn-redundant-casts%2Cwarn-return-any%2Cwarn-unreachable%2Cwarn-unused-configs%2Cwarn-unused-ignores%2Cextra-checks
Bug Report
Unpacking a list into multiple variables when the list itself is (partially) created by unpacking another iterable the type inference is faulty
To Reproduce
Expected Behavior
Mypy infers
versionanddescandstr | None(if you want to go very far you can even inferversionasstrbecause str.split never returns an empty list, but that is not my expectation)Actual Behavior
Mypy infers version as str and desc as None
Your Environment
Mypy playground: https://mypy-play.net/?mypy=latest&python=3.12&flags=strict%2Cstrict-bytes%2Ccheck-untyped-defs%2Cdisallow-any-decorated%2Cdisallow-any-expr%2Cdisallow-any-explicit%2Cdisallow-any-generics%2Cdisallow-any-unimported%2Cdisallow-incomplete-defs%2Cdisallow-subclassing-any%2Cdisallow-untyped-calls%2Cdisallow-untyped-decorators%2Cdisallow-untyped-defs%2Cno-implicit-reexport%2Cno-strict-optional%2Cstrict-equality%2Cstrict-equality-for-none%2Cwarn-incomplete-stub%2Cwarn-redundant-casts%2Cwarn-return-any%2Cwarn-unreachable%2Cwarn-unused-configs%2Cwarn-unused-ignores%2Cextra-checks