Colored output on GitHub Actions not enabled per default

[mowies]

I am using gotestsum inside GitHub actions to run some unit tests and noticed that the output is not colored per default. This is probably because gotestsum is not directly outputting to a real terminal. (Reference from fatih/color readme)

I needed to set --no-color=false to get it working which is not very intuitive.

I suggest to check for common CI environment variables like $GITHUB_ACTIONS for GitHub Actions and decide whether colored output should be enabled based on those variables.

[dnephin]

Thank you for opening this issue! I've mostly been using CircleCI to run tests, and github actions for other types of automation, so I had not noticed this yet. I believe CircleCI uses a pseudo terminal so that most commands believe they are running in a regular terminal and use color.

I like the idea of defaulting to color enabled in this environment, but I think we need to be careful to not assume all CI environments will support color. Checking if GITHUB_ACTIONS is set sounds like a good approach to me.