Ensure default global interpreter used is the default python in terminal

[karrtikr]

• Currently in case of global interpreters, the interpreter with the highest version is preferred:

  
  We should instead prefer the interpreter/environment which appears first in PATH, new selection order can be:

  • Look for python in PATH: python -c"import sys;print(sys.executable)"
  • If none of these exist, then it look for python interpreter with the highest version.

• Publish the auto-selection order in our docs.

cc/ @karthiknadig

[karthiknadig]

@karrtikr This should use an internal symlink that is always on PATH. That symlink should point to the selected python in a given workspace. That way python in terminal will always be python that is selected in the extension. This is easier said than done.

[karrtikr]

This is easier said than done.

Which is why I think for now we should simply select the default python in terminal instead of selecting the highest version.

[karthiknadig]

Which is why I think for now we should simply select the default python in terminal instead of selecting the highest version.

I am not sure it helps. I think it will confuse even more, because outside of VS Code when users type python in the terminal it will be a different experience. If we go with ensuring python always points to selected python, then there are clear rules, in VS Code terminal the python is the selected python, outside it will be whatever the terminal decides.

If, we go by the above plan, there are no clear rules. In, activated scenario the VS Code terminal is the selected python. But in global scenario it is not. And the global scenario, does not reflect what would happen in a terminal outside of VS Code. It is harder to define what happens.

[karrtikr]

I understand that's the ideal solution, but I'm just talking about improving the default experience.

But in global scenario it is not.

By default it will be, unless user explicitly changes the global interpreter. It's better than what we currently have now, where we select the highest version.

[luabud]

maybe related? #13327

[karrtikr]

@luabud Yep, #13327 would be nice (and can be done btw with the terminal exp), but I think we should still change the auto-selection order to select default python configured in the system.

For eg. most codespaces, or dev containers are configured to use Python on PATH by default, it can have the right dependencies already installed.

[pfmoore]

For eg. most codespaces, or dev containers are configured to use Python on PATH by default, it can have the right dependencies already installed.

Codespaces and dev containers are not the typical user setup. The py launcher is the standard (PEP 397) means of accessing Python on Windows, and not supporting it would make the user experience for people using the python.org distributions of Python more difficult (i.e., need customisation to work as expected).

[karrtikr]

FWIW extension can be configured to use the py launcher by default by adding the following to User settings:

"python.defaultInterpreterPath": "py"

and then syncing settings across all devices. Only a one time customisation is required.