How to make `default.nix` directory import work properly?

[emanueljg]

I want Haumea to automatically convert directoryToImport imports to directoryToImport.default imports IF the directory contains a default.nix.

Reason is as follows:

Let's say I have two types of directories:

1. Directories without default.nix in them
2. Directories withdefault.nix in them.

In the first scenario, it's a case where I want all files in the dir without question (which is why I started using Haumea in the first place). But the second scenario is more for when I want a more portable directory structure and/or want to be more precise in what modules I want to import in the dir (example in this case being NixOS configuration). This second scenario becomes a bit clunky to solve. I have to write directoryToImport.default to actually import the directory, which is unneccessary, ugly and removes the dynamic ability in going back and forth between importing a loose nix file and a directory without changing its file path.

How do I do this?

[ratorx]

I'm not 100% sure which of these 2 you want:

1. Given a directory with a default.nix, add all attributes from default.nix and also have 1 attribute per non-default.nix file.
2. Given a directory with a default.nix, add all attributes from default.nix and ignore all non-default.nix files.

If you want 1), then you can use the haumea.transformers.liftDefault.

If you want 2), you can implement it yourself using your own transformer, but possibly it might be a bit tricky to determine which of the attributes are sub-directories vs nix files.