IntelliSense doesn't work in some third-party packages. But when Pylance is disabled, the IntelliSense can work.

[Zionshang]

Environment data

• Pylance version: v2024.10.1
• OS and version: Ubuntu20.04
• Python version (& distribution if applicable, e.g. Anaconda): 3.8.10
• Editor: vscode

Code Snippet

I installed the package mujoco via pip.

pip3 install mujoco

In python, the following code can be run successfully

import mujoco

xml = """......"""  # value has been ignored
model = mujoco.MjModel.from_xml_string(xml)

But neither autocomplete nor IntelliSense work

Repro Steps

I've tried a few methods

1. Choose the right interpreter
   
   All the interpreters have tried, but nothing works
2. Edit the file settings.json in User environmet.

    "python.languageServer": "Pylance",
    "python.analysis.extraPaths": [
        "~/.local/lib/python3.8/site-packages"
    ],
    "python.autoComplete.extraPaths": [
        "~/.local/lib/python3.8/site-packages"
    ]

I've determined the package is installed at ~/.local/lib/python3.8/site-packages via pip3 show mujoco. But still not working.

Expected behavior

I found out when I disable the Pylance by

    "python.languageServer": "Jedi",

the autocomplete and IntelliSense can work normally.

Actual behavior

What is strange to me is that some packages like numpy are installed in the same path with mujoco, but numpy 's autocomplete and intellisense can work normally.

Summary

Is this a problem with the mujoco package or a problem with Pylance?

• If it is a problem with the package, why does the IntelliSense work after Pylance is disabled?
• If it is a problem with Pylance, why does numpy's IntelliSense work?

I would be very grateful if you could answer that question, because I spent a long time on it.

[rchiodo]

Thanks for the issue. The "problem" here is that Mujoco is a wrapper around native code. Pylance cannot read native code in order to find the necessary information to display your intellisense. This is because Pylance doesn't run python code. It's a static analyzer.

You can tell that by looking at the install of Mujoco:

A good portion of the public interface is in .pyd files (native python modules).

Mujoco would have to provide type stubs in order for Pylance to find the necessary information.

See this issue from Mujoco where people had similar problems with Pycharm:
google-deepmind/mujoco#244

Jedi, on the other hand, is a python app. It actually loads Mujoco into a python runtime and can inspect the native parts that way.

[Zionshang]

@rchiodo Thank you for the answer, very thorough and concise!