Snapshot testing with insta

[lcnbr]

I am trying to integrate crane into a rust crate that uses snapshot testing but I cannot figure out how to make it work. I am using insta for the snapshot tests, and when running the exact same cargo nextest command in my devshell I get no failures. However when running nix flake check, all snapshot tests fail. Does anyone have experience with this sort of setup?

See https://github.com/alphal00p/spenso for the flake.

[a-kenji]

Does your derivation have access to the snapshot test files?
It could be that:

 src = craneLib.cleanCargoSource (craneLib.path ./.);

filters them out and you need to include them through a custom filter.

You could check that with cntr: https://github.com/Mic92/cntr and enter nix build sandbox.

[ipetkov]

I believe this is correct, you will need a custom source filter (as linked above) to include the *.snap files. By default craneLib.cleanCargoSource will only keep *.rs and *.toml files

[lcnbr]

I tried :

src = lib.cleanSourceWith {
        src = craneLib.path ./.; # The original, unfiltered source
        filter = path: type: (craneLib.filterCargoSources path type) || (builtins.match ".*snap$" path != null);
      };

but that did not fix it..

[lcnbr]

Nevermind! It worked!