[Feature] support no_color env to disable ansi_color output

[ducaale]

It would be nice to control the coloring via an environment variable. My use case is that I have jq running inside wasm-terminal and would like to suppress its ansi_coloring when wasm-terminal detects that jq's input is being piped to another program (WASI's isatty is not supported in the browser).

I know that I can disable coloring via the -M flag but it would mean I have to add a special case in wasm-terminal as opposed to NO_COLOR which is supported by an increasing number of CLI programs.

See https://no-color.org/

[geirha]

Sounds like a good idea. Meanwhile you could use a wrapper script or function to add support for it

jq() {
    if [ "${NO_COLOR+set}" ]; then
        command jq -M "$@"
    else
        command jq "$@"
    fi
}

[andrewrothman]

I am seeing this as well using Acme from plan9port on macOS. Acme's built-in terminal emulator "win" does not support ANSI colors at all, so I use a wrapper script in $HOME/bin/acme to set NO_COLOR=1 FORCE_COLOR=0.

I followed @geirha's advice (thanks!) and made a similar wrapper script for plan9port's rc(1) shell. Sharing below...

#!/usr/local/plan9/bin/rc
# wrapper for jq. disables colors in an acme win.
# make sure to "chmod +x" this file and put it in a directory listed in your $PATH.

if (~ $TERM_PROGRAM 'win') { /usr/local/bin/jq -M $* }
if not { /usr/local/bin/jq $* }