Search for default statix.toml according to xdg spec

[MrQubo]

Closes oppiliappan#165

I just followed this: https://specifications.freedesktop.org/basedir/latest/

[MrQubo]

I noticed that the list of subcommands, where --config flag is available, is incomplete.

[mightyiam]

Thank you for this contribution! Don't you think statix is a project-specific tool?

[MrQubo]

Thank you for this contribution! Don't you think statix is a project-specific tool?

I think some of the warnings are useful to have when editing nix files. I configured my editor to run statix on every nix file and display warnings. But I wanted to disable one of the warnings. They way it works in this PR, statix will pick first statix.toml it tries, so any project-specific statix.toml would be used instead of user-configured one.

[mightyiam]

I want you to have what you want. Just trying make sure things land correctly.

Wouldn't some would claim that this is impure behavior because their linter looks for a config file outside of their project dir?

[MrQubo]

As it is currently statix already looks for statix.toml in your home folder and root directory if the project doesn't have it's own statix.toml. If someone creates a project and want to ensure that statix runs the same on every developers machine, they should put a statix.toml in the root of their project (even if it's empty file), or by explicitly calling statix with --config arg in project's tooling scripts.

The way I see it, is that this PR let's you change the default settings of statix for every project and file that doesn't have statix.toml.

[mightyiam]

Okay, I agree.

Would you be willing to contribute a test for existing behavior of reading a config file, prior to this behavior change?

[MrQubo]

Would you be willing to contribute a test for existing behavior of reading a config file, prior to this behavior change?

I never wrote filesystem integration tests like that, is there some example of that in the repo?

[MrQubo]

I also modified statix dump to print user's statix.toml from xdg config.
I think that makes sense from the UX perspective. User would put statix.toml in xdg config when he wants to change some default settings of statix. statix dump is used by the user when he wants to create a new project, so it's likely that the user might want to use his own defaults.

[mightyiam]

Hrm... no, I don't think we have general integration test tooling here. Would you be interested in contributing the beginning of that? Perhaps some neat crate that provides a convenient API.

[MrQubo]

Would you be interested in contributing the beginning of that? Perhaps some neat crate that provides a convenient API.

No, not really.