tty: add color support for iterm2

[dlionz]

Added iterm2 to the tty.js file for terminal color support #27609

Checklist

• make -j4 test (UNIX), or vcbuild test (Windows) passes
• tests and/or benchmarks are included
• commit message follows commit guidelines

[BridgeAR]

@dlionz thanks for your contribution! This does not seem to be correct though. The terminal supports "TRUECOLOR", so 16 million colors, not only 256. Are you also certain that process.env.TERM is set to 'iterm2'? And are there any other terminal related environment variables set?

[BridgeAR]

@dlionz I removed the test output from your description above.

[dlionz]

@BridgeAR Ah I see, sorry I geuss I didnt understand before.
this is my output when I console.log(process.env.TERM): xterm-256color
so then does my change need to look like this

const TERM_ENVS = {
//code
'xterm-256color': COLORS_16m
}

thanks again

[devsnek]

don't forget about xterm-256color-italic, tmux-256color, and tmux-256color-italic (all of these iterm2 configs support 16m)

[BridgeAR]

We already have a check for /^xterm-256/. The main problem with that environment variable is that it's used by multiple terminals and some do not support true color. Is there anything to clearly identify that the terminal is indeed iterm2?

[dlionz]

@BridgeAR I see on the process.env object this property TERM_PROGRAM: 'iTerm.app but reviewing further down the page I see a hook for this already. So I suppose I don't have anything to contribute as this time. Or later today I can go find new some terminals to try.

switch (env.TERM_PROGRAM) {
    case 'iTerm.app':
      if (!env.TERM_PROGRAM_VERSION ||
        /^[0-2]\./.test(env.TERM_PROGRAM_VERSION)) {
        return COLORS_256;
      }
      return COLORS_16m;
    case 'HyperTerm':
    case 'MacTerm':
      return COLORS_16m;
    case 'Apple_Terminal':
      return COLORS_256;
  }

[devsnek]

taking a deeper look, iterm reports COLORTERM, and process.stdout.getColorDepth() returns 24.

[dlionz]

Closing this pr as I didn't realize my update was already implemented. Thank you for your time