Provide a public API to set the environment to a given path

[brettcannon]

I have an extension that currently changes the python executable being used by setting it in the user or workspace settings.json (depending how the user chooses to do it).

In the description of https://github.com/microsoft/vscode-python/wiki/AB-Experiments#deprecatepythonpath, I can't really see any way for an extension to update the python used by the vscode-python extension after the move to stop using the settings.json.

So, this is a request to provide an API/command to provide parity with what was already available prior to this change (or if there is already a way to do it, document it in https://github.com/microsoft/vscode-python/wiki/AB-Experiments#deprecatepythonpath).

Originally posted by @fabioz in a discussion

[fabioz]

@brettcannon do you see any reason not to provide such an API? (i.e.: would it be Ok if a pull request was created to do that?)

The one thing I can think of is that there could be a security risk if any extension could set the interpreter, but maybe it'd be Ok if the python extension confirmed with the user (requiring a UI confirmation) when such a call is made?
-- although if the user already installed a malicious extension, I'm not sure whether such confirmation would make any difference, so, maybe that'd be a bit overzealous...

[brettcannon]

My immediate concern is a wayward extension changing the selected interpreter without the user wanting/asking and us having to deal with the fallout. After that it's thinking such an API through, are there other concerns, etc.

Basically the question is whether we want to be an integration point (and I suspect the answer is "yes", but not in our current form).

[tonka3000]

What do you mean with but not in our current form?

[brettcannon]

@tonka3000 we have ideas to restructure some things which would impact how such an API would be exposed.

[tonka3000]

I have the same use case (explained in #16915). I understand the security concerns but in my use case these are mandatory functions.

At least I would need a command to know which interpreter is active, something like

const interpreterPath = await vscode.commands.executeCommand("python.interpreter") as string;

That way I can at least show the user a popup that he/she needs to change the interpeter. In my case the user will get a lot of such toast message which is never really a good UX.

Maybe have a "set command" which would inform the user that the change was done (and if the user like could be undone) could also be an option.

@brettcannon

• Do you see any chance to get at least the "get interpreter" command before the new python interpreter selection is the only way of selecting the interpreter
• Is there a chance that you will keep the old mechanism (python.pythonPath)

[brettcannon]

@tonka3000

Do you see any chance to get at least the "get interpreter" command before the new python interpreter selection is the only way of selecting the interpreter

Eventually, yes. We just don't have a timeline right now.

Is there a chance that you will keep the old mechanism (python.pythonPath)

No as we already removed it.

[fabioz]

A way to get the interpreter is already provided.

See: https://github.com/microsoft/vscode-python/wiki/AB-Experiments#deprecatepythonpath for more details (it provides both a command as well as an extension API which even notifies about changes).

This discussion is mostly about having a way to set the interpreter, which is no longer available.

[tonka3000]

Thanks for the info @fabioz

[brettcannon]

Moved to #16994