Add support for a custom config directory

[rauhul]

This repo uses a lot of dotfiles for config. The customization is nice, but putting all of them at the repo root is very annoying and distracts viewers on the repo home page with a bunch of ci details.

Instead we should be able to set a custom configuration_directory relative to the repo root that contains the dot files. This could be limited to .github/configuration, but I'd rather it be not restricted. For instance I might want to include config files for other tools not used by workflows provided by repos in the same directory, and config for tools that aren't even visible to GitHub (actions).

[madrob]

Another idea might be to do like pyproject.toml and all the config for each tool gets their own section but in the same file

[shahmishal]

+1 on the idea of having this under .github dir. Maybe .github/workflows/<configuration_dir>

[MahdiBM]

Similar to #77 (comment), we need to make sure this plays well enough with the existing tools.

I mentioned accepting custom paths for .swift-format in sourcekit-lsp to @ahoppen, but he didn't think it's necessary.
I guess with such a feature in this CI repo, and with .swift-format possibly being moved to another place, we now have a reason for accepting custom paths for .swift-format in sourcekit-lsp, and I'd think @ahoppen will be OK with that considering we'll have a usecase for such a feature.

Still, it'll interrupt the VS Code users if the config files are moved to a different directory before sourcekit-lsp that is bundled in the toolchains recognizes that. Even then the repos will need to have custom .vscode/settings.json or .sourcekit-lsp/config.json files to be able to tell sourcekit-lsp where to look for the configs.

So ... I agree with the idea but not sure how easy it'll be.

[ahoppen]

A thing I really want to caution against is that if we put the .swift-format files outside of the package’s repo, users won’t be able to easily apply that format style locally because they are missing the configuration file. I am worried that this may significantly disrupt local development workflows.

[rauhul]

This request is about a location for that file in the current repo but not at the repo root.

[ahoppen]

Maybe I’m misunderstanding but say you want to put your .swift-format file in your-project/.dotfiles/.swift-format. Then the GitHub workflow would be configured to use that .swift-format file. If a new contributor sees that the formatting was incorrect, the naïve solution would be to run swift-format -ir . on the repo. But that wouldn’t pick up the .swift-format file because it’s in a non-standard location. Similarly, SourceKit-LSP wouldn’t pick up the .swift-format configuration file for in-editor formatting.