Show the REPL/output with cursor at the bottom (#792)

[glebovmaksim]

What has Changed?

Eliminates the state and always shows the REPL/output with cursor at the bottom when using command/shortcut ctrl+alt+c o.

Fixes #792

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Ping @PEZ, @kstehn, @cfehse, @bpringe

[PEZ]

I don't think we can remove the scrolling in that append method. When the window is not visible it should still be scrolled when made visible. So my guess is that this will not work when the output window is in the same tab group as the file where the evaluation happens. I'd be happy to be wrong about it, though. No fan of state. 😄

[glebovmaksim]

The output window will always be scrolled to the bottom when made visible via the ctrl+alt+c o. It also works with "Open Results Window" button on hover (it's the same command) and with peek to definition. When using another methods (clicking on tab / ctrl+tab etc) the scrolling will not work. I'll revert that change if you consider it bad behaviour. This will require extra check to prevent double scrolling and will no longer be simple, but maybe it is necessary.

[bpringe]

I like your changes here, but I agree with @PEZ that keeping the auto scroll behavior even when the output window is clicked via a tab and when there are unread eval results, is best. So your change would be additive and not remove any existing functionality. I too would like to get rid of that state, but the behavior (as desired) seems inherently stateful.

I'm not sure that preventing double scrolling is really necessary, as it's a pretty insignificant thing, I would guess, and an idempotent operation. But if it's pretty simple to prevent, then we should.

[PEZ]

Will you maybe have time to finish this during Christmas, @glebovmaksim ? 😄

[ieugen]

Hi @glebovmaksim ,

I would like to see this through since I usually code with split window and having Calva output there messes with my flow.

Are you interested in continuing this?
Are you open to let someone else continue?

I would give it a shot, even though I know quite little about typescript and even less about vscode (that is how much I want to see this though).