Rust derivation needing a "missing" crate

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1

I’m updating a derivation.nix for parinfer-rust to work with a pull request that adds emacs support.

Running cargo build with direnv works just fine, but if I try to use nix-build ., it can’t find the “emacs” crate. I’ve deduced from this that building the derivation uses some snapshot of the crates.io repository that doesn’t include this crate.

And so I found https://github.com/NixOS/nixpkgs/blob/6e4ed2ed0b116adaedeb71d3c9824e89d827dd60/pkgs/build-support/rust/crates-io.nix , which does not have the emacs package in it.

So, first, am I right so far? Is this the right direction?

If I wanted to add a package to crates-io.nix, how would I do it? It looks like it is generated, but it has manual adjustments to it, which seems bad.

But then, is there a way to convince nixpkgs to build a crate without updating this file? Either in the derivation itself or using an overlay?

2

OK, this is resolved. The answer was, dumbly enough, that the moduleSha256 needed to be updated and the old source was cached under the old SHA.

3

Good to see that problem solved! I would suggest that you mark the topic as solved using your own comment.