Emit progress state escape codes

[albertlarsan68]

Emit progress state escape codes when drawing progress bar.

Fixes #11432

[rustbot]

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[weihanglo]

Thanks for the pull request, and sorry for the long wait.

This is a UI change. Could you demonstrate demo GIFs or videos for it? It would be helpful if you could provide the result on both msvc and mingw.

In addition, do you have the official documentation at hand about this escape code? CodeEmu doc doesn't seem to be official I feel like.

[weihanglo]

This is Windows-only feature, right? Is it possible to add #[cfg(windows)] for all relevant code and items?

Also, having doc comments on each new items would be fantastic. Thanks!

[albertlarsan68]

I do think that other terminal emulators may also implement those, but I can't verify now.
It seems like per alacritty/alacritty#5201, it won't get this support, however.

[albertlarsan68]

In addition, do you have the official documentation at hand about this escape code? CodeEmu doc doesn't seem to be official I feel like.

As per microsoft/terminal#8055, the ConEmu style is the implementation reference.

[albertlarsan68]

Here is a screen recording of running cargo check with b60dc0d (I recommend watching it at x2 speed):

2022-12-21.14-57-40.mp4

Notice the bar in the taskbar, and the circle getting bigger / fuller at the top left corner.

[weihanglo]

Thanks for the screen recording!

Unfortunately on macOS it doesn't seem to compile: https://github.com/rust-lang/cargo/actions/runs/3749845063/jobs/6368801382

I am still uncertain the adoption rate of this non-standard escape code. Does the majority of terminal emulators handle or ignore this well? Sorry being so conservative but I've seen some issue around “escape code not recognized” sometimes. That's also why I suggested adding #[cfg(windows)] at the very first, and even on Windows there are a bunch of different emulators. I'd recommend collecting the usage and support data before rolling out this feature :)

[albertlarsan68]

Current testing progress:

Terminal	Support
Windows Terminal	✅
Git MinTTY	✅ (but reset only happens when progress is set to 0)
Alacritty	❌ (Feature seemingly refused)

Procedure:
run echo -e "\e]9;4;1;50\e\\" for Linux-like, or copy the line below for Powershell Core and paste it at the prompt.
Reset with echo -e "\e]9;4;0;50\e\\" or the second line. If that doesn't work replace the 50 with a 0.

"`e]9;4;1;50`e\"
"`e]9;4;0;50`e\"

[weihanglo]

#11436 (comment) was a good try. Thank you. I'll probably split Support to two columns:

• Support the display of the progress bar or not.
• If not supported, would it break things or just ignore the unrecognized escape code?

Marked this as S-blocked as it need more data to ensure it won't break the majority from different terminal on Windows.

[weihanglo]

Personally I love this kind of good UI enhancement with the system. We just need more data to make sure it is safe for most people. Going to close due to inactivity. We still look for people investing in surveying.

Thank you anyway!

Edited: track in #11432.