So I just dove down a rabbit hole (microsoft/terminal#11057) and what I found interesting is that WT_SESSION isn't 100% reliable (microsoft/terminal#11057 (comment), microsoft/terminal#13006). Basically, if Windows Terminal is not the first executable, but cmd.exe or powershell.exe starts up and then "attaches Windows Terminal to itself," then this environment variable isn't set.

This one might be tricky. AFAIK, the only way to determine if a terminal supports truecolor is by using heuristics on environment variables, which can be somewhat 'hacky.'

I've discovered this crate called supports-color, which is quite popular and should meet our needs. Unfortunately, according to the code, it states that all terminals in Windows do not support truecolor 🤔, which is not accurate.

This crate is based on another project with the same name: https://www.npmjs.com/package/supports-color, and it actually does what we need. It returns 'truecolor' for Windows after a certain version chalk/supports-color#71

t returns 'truecolor' for Windows after a certain version chalk/supports-color#71

In that terminal issue one they did recommend just assuming that Windows can support true color as long as we're running on 10 (microsoft/terminal#11057 (comment)), so that certainly could be a valid option. But at the same time, I ran the custom_colors example from owo-colors on "plain" command prompt on Windows 10 and got results that weren't pretty 🤷

After a bit of digging, I've found that GitHub checks if the terminal is a virtual terminal, and then falls back to COLORTERM:
https://github.com/cli/go-gh/blob/debe718854c4ef26135c2348fd91db360fe5bae8/pkg/term/env.go#L72C47-L72C47
https://github.com/cli/go-gh/blob/debe718854c4ef26135c2348fd91db360fe5bae8/pkg/term/console_windows.go#L12-L18

Whatever the GitHub CLI does could be the way to go. It certainly has plenty of user testing.

FYI, I've opened an issue on supports-color 👉 zkat/supports-color#17

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This is a bit of a stretch, but colored, with built-in color support checking, is now maintained again. IDK if we're interested in switching back and requesting improved Windows support there.

Could be worth it, especially with colored-rs/colored#90 which could simplify the language template.

This pull request has been automatically marked as stale because it has not had recent activity. It will be closed if no further activity occurs.