Local Echo: Predict the display of remote characters

[MarnoRossouwX]

Description of the new feature/enhancement

Predict characters that will be displayed in the terminal without having to wait for the shell. This is done in the 1.51 release of Visual Studio Code and is explained in detail on its release notes: https://code.visualstudio.com/updates/v1_51#_local-echo

As explained in the Visual Studio Code release notes, this will be particularly useful when working over an ssh connection.

Proposed technical implementation details (optional)

[zadjii-msft]

Well that's certainly an interesting idea. There's a little more discussion here. Specifically that calls out not doing this in the alt buffer, which I think is a reasobaly assumption.

From purely an implementation standpoint, I wonder if there's an easy way to do this with "overlays" like we had considered years ago for popups. I'm not sure that we'd want to actually populate the buffer with these "predicted" contents, we'd need some way to keep the predictions separate.

[DHowett]

This sounds a lot like mosh.

[djsavvy]

Does this really need to be implemented in the terminal itself? I feel like delegating this functionality to mosh makes more sense.

[gakio12]

mosh requires a server component to be installed. The functionality in VSCode does not require a remote component.