Add pre-commit hook for cleaning up mixed-line endings

[drsooch]

Figured I'd offer a solution for #2678. I don't use nix so I'm not sure if there is anything that needs to be done to integrate in nix (also not sure if it's even necessary). Most of the file commits are the line endings with a few interspersed stylish-haskell changes.

[michaelpj]

Hmm, isn't there a git setting that sorts this out for you? Something with git config core.autocrlf?

[jneira]

Hmm, isn't there a git setting that sorts this out for you? Something with git config core.autocrlf?

yeah core.autocrlf=input to ensure you use LF endings (the used ones in the remote repo) but:

• git suggests you core.autocrlf=auto in windows as default, which keep CRLF in your local and replaces them with LF on commit
  • that has its own caveats: if you share those files from the local copy (for example generating a tarball to upload to hackage) they still will have CRLF and that will make tests in hackage fail. Yes, that happened: Failing test with whitespace mismatches for hls-splice-plugin #1808
• although we have line endings enforced in .editorconfig most editors does not honour it by default (vscode amongs them) you have to install a specific extension (as mentioned here: https://github.com/haskell/haskell-language-server/blob/master/docs/contributing/contributing.md#style-guidelines)
  • so you have to remember install the plugin

So maybe add a precommit hook to enforce it is not a bad idea

[jneira]

omg all those files had incorrect line endings???? 🤦

[jneira]

yeah, as described in the issue: #2678

[jneira]

what about create a .pre-commit-config.json in the repo to make a little bit more easier and discoverable? docs could link to the file in that case

[drsooch]

I can do that as well!

[drsooch]

Although, the pre-commit hook is part of .gitignore. I can envision some users use their own personal pre-commit hook and having one in source control may cause issues?

[jneira]

So maybe add a precommit hook to enforce it is not a bad idea

otoh you have to remember install the hook, like you have to remember install the plugin to honour our existing enforcing mechanism, .editorconfig 🤷

the advantage of the hook is it is applied always for sure (once is installed), even if you editor (notepad?? :-P) does not have support for .editorconfig

[jneira]

What about fix the formatting existing hook to make it use LF in its formatting (or at least not change them to CRLF!!!)? we would have the two features with one hook

[drsooch]

What about fix the formatting existing hook to make it use LF in its formatting (or at least not change them to CRLF!!!)? we would have the two features with one hook

Ooo I didn't realize stylish-haskell could fix line-endings. I guess the only downside is it won't get run on a bunch of excluded files?

[Anton-Latukha]

Special thanks for converting those files to the initial line ending. Converting back - would solve Git diff rebases. I thought that is the first thing to do on return, before thinking further, it is already done here. Thank you.

[jneira]

What about fix the formatting existing hook to make it use LF in its formatting (or at least not change them to CRLF!!!)? we would have the two features with one hook

Ooo I didn't realize stylish-haskell could fix line-endings. I guess the only downside is it won't get run on a bunch of excluded files?

not sure if it could modify line endings but it should not change the existing ones, like it is doing for me lf -> crlf
that alone would be an improvement

[Ailrun]

Is there a way to put the config into nix setting?

[drsooch]

I don't use nix so I have no idea, any help would be appreciative.

[jneira]

nix doesn't support windows so I suppose it is not necessary?

[Ailrun]

Oh, makes sense.

[jneira]

thanks!