Jupyter API to get Env associated with Notebooks

[DonJayamanne]

See microsoft/vscode-jupyter#15987

Should also fix microsoft/vscode-jupyter#16112
Should also avoid Pylance having to monitor notebook changes and then trying to figure out the Environment for a Notebook.

@rchiodo @heejaechang @debonte Please can you let me know if this works
I.e. going forward (we can plan how we roll this out)

• Pylance can use just Python extension API to get Python environment for a Uri (the uri can be a Notebook or IW uri)
• If the kernel is changed, the event onDidChangeActiveEnvironmentPath will be triggered with the corresponding Uri
• If a kernel is changed to say a Non Python Kernel, then its triggered again, but the active interpreter for that Uri will be the same as the worksapce interpreter

I believe this should simplify things.
@karthiknadig /cc

[rchiodo]

Pylance having to monitor notebook changes

For what it's worth, we don't do this now. The vscode-languageclient-npm module does. So theoretically any language can listen for notebook events, not just Pylance.

[DonJayamanne]

So theoretically any language can listen for notebook events, not just Pylance.

How does Pylance get the Python env associated with a notebook?

[rchiodo]

How does Pylance get the Python env associated with a notebook?

We ask the python extension for the environment for the current file. This happens after we get the notebook changed event.

[DonJayamanne]

We ask the python extension for the environment for the current file.

awesome, then this change will make this workflow work properly

What I'm getting at is Pylance will not need the registerJupyterPythonPathFunction (private) api anymore and you can use the official Python extension API. this way others language servers can benefit from this, else if some other extension like Ruff or Jedi (if there were other extension) need this, then they would need a new API or a similar hook...

I.e. just use getActiveEnvironmentPath(resource?: Resource): EnvironmentPath
and onDidChangeActiveEnvironmentPath to detect changes to Python envs associated with Notebooks and the like (still free to use notebook change events as well).