feat: support searching for config in XDG_CONFIG_HOME and $HOME/.config

[k4yt3x]

This code will, in addition to the current directories being searched, also look for the config file in XDG_CONFIG_HOME/golangci and $HOME/.config/golangci.

For desktop applications, I find it not very elegant to leave the .golangci.yml in my home directory. I usually prefer to put config files in XDG_CONFIG_HOME ($HOME/.config) to avoid making a mess in the home directory. I do not want to manually specify a config path with --config since it will overwrite the repository's config if one exists. I reviewed the code and found that golangci-lint does not seem to support finding the config in XDG_CONFIG_HOME, so I'm submitting this PR in recommendation of adding this support.

Setup

I have a configuration file located at $HOME/.config/golangci/golangci.yml. I am using golangci-lint's repository for the demo below. I have removed the repository's built-in .golangci.yml so it will search for the global config.

Previous Behavior

Previously, golangci-lint does not search for the said directories above, only $HOME:

New Behavior

Now, if the old recursive search does not yield any results, it will also search the global config directories:

...and if we restore the repo config it still finds that first:

Fixes #4554

[boring-cyborg]

Hey, thank you for opening your first Pull Request !

[CLAassistant]

All committers have signed the CLA.

[ldez]

related to #4554

I suggest looking for the issues or creating an issue before opening this type of PR.

[k4yt3x]

I suggest looking for the issues or creating an issue before opening this type of PR.

I actually did search, for both issues and PRs, neither returned what I was looking for.