reversed(Enum)

[MeGotsThis]

As a semi-continuation of #2891, using mypy 0.510.

import enum

class Letters(enum.Enum):
    A = 0
    B = 1

l: Letters

for l in Letters:
    print(l)
for l in reversed(Letters):
    print(l)

Running mypy gives this error

enum-test.py:11: error: Incompatible types in assignment (expression has type "Enum", variable has type "Letters")

Line 11 is the 2nd for loop.

[elazarg]

Is it not precisely #3210 ?

[ilevkivskyi]

It looks very similar, but I propose to keep this open, so that we will not forget to add this example to tests when fixing #3210.

[gvanrossum]

Explain to me again why this is not a duplicate of #3210? If we want to remember to add both examples to the tests we can just add this example to #3210. E.g.

from enum import Enum

class E(Enum):
    one = 1

reveal_type(list(E))  # 'builtins.list[enum.Enum*]'

reveal_type(reversed(E))  # 'typing.Iterator[enum.Enum*]'

[ilevkivskyi]

All examples in this issue now work correctly on mypy master.