Pylance(reportUnknownVariableType) when enumerate() is used with parameter start

[hflamme]

Environment data

• Language Server version: 2021.11.2
• OS and version: Ubuntu 20.04.3 LTS
• Python 3.9.5

Expected behaviour

Within the following code

a: list[int] = [1, 2, 3, 4]
b = [c for i, c in enumerate(a, start=1)]

the type of b should be inferred as list[int].
This is the case when removing the start argument, i.e. for

a: list[int] = [1, 2, 3, 4]
b = [c for i, c in enumerate(a)]
print(b)

types are asserted just fine,

Actual behaviour

Pylance(reportUnknownVariableType) for variable b and c (see below).

Logs

[erictraut]

Thanks for reporting the problem. I think this has been fixed since the last release of pylance. I'm able to repro it with the last released version, but I'm no longer able to repro it with the latest code. A new version of pylance will be released within the next day or two, and that should address the problem.

[hflamme]

Perfect, thanks

[bschnurr]

This issue has been fixed in version 2021.12.0, which we've just released. You can find the changelog here: CHANGELOG.md