Allow user to set their own custom activation commands for the interpreter

[karrtikr]

Upon creating a terminal, an activation command to activate the current environment is sent to the terminal.

There are often issues like #8770, where environment is not activated due to extension sending the wrong activation commands.

Example: An activation command used to work with conda x.x.x, but conda y.y.y changed something so it is no longer valid. And if the extension does not keep up with the change, activating the environment would fail.

Allow user to set their own activation commands for the interpreter they're using. Often they know the correct activation commands as you can notice in #8770.

[DonJayamanne]

@karrtikr @karthiknadig Please see comments in #8770 (comment)

I agree with you about omething so it is no longer valid. And if the extension does not keep up with the change,
And also I believe in an alternative solution, which is to fix/deprecate the hack instead of allowing users to customize the commands. Fix it for everyone. E.g. on my machine i too don't need the double activation.

I believe only seasoned users would go into VS Code settings to customize the activation commands. Other would probably give up and just activate manually or file issues or even worse..

[karrtikr]

And also I believe in an alternative solution, which is to fix/deprecate the hack instead of allowing users to customize the commands

Yes we should definitely fix it. We should do our best in sending the correct default commands. But having support for custom activation command also seems like a nice workaround to have for the user.

There're things we can do for discoverability. For eg. we can test if an activation failed for a user and notify them of this option.

[xq114]

The issue is also here for me in python interactive window. It cannot detect my ipykernel package.

I guess it is due to my changing the default activation command (for some reason). No correct activation command is here to tell the interactive window where to find my ipykernel package. It just send an error like this:

[Extension Host] Info Python Extension: 2020-01-21 12:38:39: Activation Commands received undefined for shell cmd

[DonJayamanne]

@xq114 Please could you file a separate issue with the details. I would like to get to the bottom of the issue you are experiencing. Hence move the discussion into a separate issue that discuss that here. We're looking at #8928 which could resolve the issue you are encountering and make this solution/issue unnecessary.

[1st]

+1 I also need to set some env variables (db name, db user and password) when opening a new terminal tab. I do it now by source ~/.zshrc where I have such variables set. But will be better to set these variables per-project, because each project needs its own DB and credentials, and I don’t want to store them in a file like settings.py for known reason.

Waiting for this feature. Hope that this will help me to set env variables in the terminal, as well as do other shell commands (like change directory to src when open a new terminal window).