Not respecting isinstance for type narrowing using boolean short circuit

[john-dicarlo]

# example.py

foo: list[str | int] = [0,1,2,3,'strings', 'as', 'well', 'here', 'bar', 'baz']

for i in range(len(foo)-1):
    if (isinstance(foo[i+1], str) and foo[i+1].upper() == 'BAR'): #  error: Item "int" of "str | int" has no attribute "upper"  [union-attr]
        print('FOOBAR')

I figure this type test is simple enough that mypy should know foo[i+1] must be a str.

Your Environment

mypy 1.6.1 (compiled: yes)
Python 3.10.12

mypy --strict ~/example.py

[ilevkivskyi]

Duplicate of #7339