Interesting! I've gotta check this out. If it passes all the tests we have so far and works reasonably well (like, changes it makes are reasonable changes, such as: The file was probably wrong) on bigger existing files are a good start.

But yeah, it needs to be tested out for a bit :)

Looks good mostly to me! I would like to add some more test cases, but otherwise I think it's good work! Thanks for working on this, I have been too busy to really look at nix-mode for the last few months, but I definitely think we can merge this.

I do think I want to keep nix-indent-line around and have 3 options for nix-indent-function. The main rationale for this is that we can at least in theory support more corner cases with nix-indent-line than smie-indent-line. I could be wrong on this and smie-indent-line is strictly better. Either way, keeping both seems like a safer decision.

Thanks! This works really well. I've release 1.4.0 with these changes and making smie-indent-line the default.

@j-piecuch Very good job on this! :)

This pull request has been mentioned on Nix community. There might be relevant details there:

https://discourse.nixos.org/t/nixos-weekly-10-redox-on-nixos-ad-hoc-container-images-nix-mode-el-static-site-deploys-a-job/3296/1