Use ANSI codes to report progress

[albertlarsan68]

Problem

When the terminal is not in focus, there is no way to know the progress state of the compilation.

Proposed Solution

There exist escape codes that allow control of a "progress meter", that for example is shown on the taskbar in Windows.
Winget uses them, and the implementation can be seen at https://github.com/microsoft/winget-cli/blob/master/src/AppInstallerCLICore/VTSupport.cpp. It mostly consists of adding the correct progress number, and clean up after the end.

Notes

I volunteer to make this change to this repo.

[albertlarsan68]

@rustbot label +A-console-output

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[albertlarsan68]

https://conemu.github.io/en/AnsiEscapeCodes.html#ConEmu_specific_OSC is the documentation page for it. Windows Terminal supports it, which makes it a worthwhile addition for both Windows and Linux, as WSL exists.

[albertlarsan68]

@rustbot claim

[weihanglo]

Triage: This is a cool enhancement but we need to be careful to not break people's emulators with unsupported escape code. In #11436 the author did some initial research, we'd like to see more info got collected back.

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Copied from #11436 (comment):

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\"

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Suggestions for future survey (#11436 (comment)):

Two columns in the table:

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

[epage]

Following the pattern of #12889 might offer a route for us to move forward with this

• Have an allowlist of terminals
• Have a term.progress for explicitly enabling / disabling it to workaround the allowlist until a new release is out

This also makes me wonder about using escape codes to set the window / tab title during the build to report progress.

[weihanglo]

I am totally okay if it can be turned off.

Found this resource of escape code we might want to support: https://tldp.org/HOWTO/Xterm-Title.html, though it's a bit old (1999).