Imported complex types resolve to unresolved symbols

[DonJayamanne]

@patrys commented on Fri Jan 25 2019

Environment data

• VS Code version: 1.31.0-insider
• Extension version (available under the Extensions sidebar): 2018.12.1 (language server 0.1.78)
• OS and version: macOS 10.14.2
• Python version (& distribution if applicable, e.g. Anaconda): 3.7.2 from Homebrew
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): virtualenv
• Relevant/affected Python packages and their versions: N/A

Expected behaviour

Importing a complex type like MyType = Callable[Foo, Bar] works.

Actual behaviour

Language server reports an error when the type is used: 'Foo' used before definition.

Steps to reproduce:

# foo.py
from typing import AsyncIterator, Callable

Foo = Callable[..., AsyncIterator]

# bar.py
from .foo import Foo

x: Foo

You should get an error reported for the word Foo in bar.py.

Logs

Output for Python in the Output panel (View→Output, change the drop-down the upper-right of the Output panel to Python)

Microsoft Python Language Server version 0.1.78.0
Initializing for [redacted]

Output from Console under the Developer Tools panel (toggle Developer Tools on under Help; turn on source maps to make any tracebacks be useful by running Enable source map support for extension debugging)

N/A

[jakebailey]

I believe this is a deficiency in the old analyzer, which I don't believe supports indirect imports of things from typing. The new analyzer should handle this better.

[MikhailArkhipov]

Most popular types from typing are now specialized. Additional types will come as part of #535 eventually.

[MikhailArkhipov]