Keep colors through docker output (useful for test output, green vs red)

[Trevoke]

If I understand correctly, we can pass an additional option to the docker container to let it print colors properly:

https://stackoverflow.com/a/33499558/234025

docker run --rm -it -e "TERM=xterm-256color" govim bash -l

I tried to extend Eldev-local like so but didn't get any success:

(setq eldev-docker-executable "podman"
      eldev-docker-run-extra-args '("--userns=keep-id" "--env=\"TERM=xterm-256color\""))

[doublep]

Trivial reproducer:

$ eldev exec '(eldev-warn "test")' # -> colored
$ eldev docker 27 exec '(eldev-warn "test")' # -> not colored

You can work around this by passing global option -C via command docker:

$ eldev docker 27 -C exec '(eldev-warn "test")' # -> colored

However, please don't close this, it has to be automatic. I.e. if the outer process uses colored output, the one running in Docker should do that too, because they write to the same terminal.

[doublep]

Will become automatic in 1.4, for now you can use the workaround.