[MS Language Server] Go to definition cannot traverse workspaces

[amittleider]

Currently the MS Language Server won't allow jumping to a class (using Go to Definition) if it's found in a different VSCode workspace.

Environment data

• VS Code version: 1.35.0
• Extension version (available under the Extensions sidebar): 2019.5.18875
• OS and version: Ubuntu 18.04
• Python version (& distribution if applicable, e.g. Anaconda): 3.6.7 64 bit
• Type of virtual environment used (N/A | venv | virtualenv | conda | ...): venv
• Language Server (more info How to update the language server to the latest stable version #3977): LS

Expected behaviour

Go to definition jumps to the Level1Class object

Actual behaviour

Definition not found. Below is a gif.

Steps to reproduce:

• Use this repo: https://github.com/amittleider/vscode_multi_workspace_bug_repro
• Go to the file upper_level_class.py
• Try to jump to the definition of the Level1Class object.
• It will probably say "Cannot find definition"

[luabud]

Closing in favour of microsoft/python-language-server#1196

[MikhailArkhipov]

The issue is not a bug. LS only supports single root, it is not capable of handling multiple roots, especially with different versions of Python. Extension (and Visual Studio) runs multiple LS processes, one for each root (or project in solution in VS). Said instances are not able to communicate or navigate across tree spanning multiple processes. Making LS actually load multiple roots would a major architectural redesign. Thus the issue is that not that someone made a mistake (i.e. a bug) but rather conscious architectural design limitation.

[luabud]

Closing in favour of #5132.