Cannot Pass Deps to buildDepsOnly

[Lyndeno]

Describe the bug

I want to layer dependencies onto each other for individual packages instead of using solutions like hakari to unify features across crates.

Reproduction

Try passing existing artifacts to buildDepsOnly. They are not used due to

crane/lib/buildDepsOnly.nix

Line 62 in 0cea393

cargoArtifacts = null;

.

I propose making cargoArtifacts an optional parameter that defaults to null for buildDepsOnly, such that I can optionally pass in existing artifacts to build off of. Is there a reason I am missing for why this is currently not the case?

[dpc]

I want to layer dependencies onto each other for individual packages instead of using solutions like hakari to unify features across crates.

Without something like hakari cargo is just going to start rebuilding lots of deps, AFAIK, at least ones that are not identically configured in previous and current configuration. I don't think it is going to work like how you'd like.

Passing cargoArtifacts to buildDepsOnly might be useful in some weird circumstances in theory, but I haven't yet found a use for it, and I tend to try all sorts of crazy hacky things on top of crane. :D

[ipetkov]

Hi @Lyndeno ! It is intentional (by design) that buildDepsOnly does not accept cargoArtifacts: it is meant to be the starting point for creating the initial set of artifacts. Afterwards you are free to layer/chain other derivations however you'd like (and all other functions do accept overriding the cargoArtifacts).

You may want to use something like cargoBuild/mkCargoDerivation along with mkDummySrc to customize your cargoArtifacts further before calling something like buildPackage. Hope this helps!