lix/doc/manual/rl-next/fod-failure-includes-url.md
Jade Lovelace d92712673b store: guess the URL of failing fixed-output derivations
This is a shameless layering violation in favour of UX. It falls back
trivially to "unknown", so it's purely a UX feature.

Diagnostic sample:

```
error: hash mismatch in fixed-output derivation '/nix/store/sjfw324j4533lwnpmr5z4icpb85r63ai-x1.drv':
        likely URL: https://meow.puppy.forge/puppy.tar.gz
         specified: sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
            got:    sha256-a1Qvp3FOOkWpL9kFHgugU1ok5UtRPSu+NwCZKbbaEro=
```

Change-Id: I873eedcf7984ab23f57a6754be00232b5cb5b02c
2024-06-27 22:44:16 -07:00

797 B

synopsis cls credits category
Hash mismatch diagnostics for fixed-output derivations include the URL
1536
jade
Improvements

Now, when building fixed-output derivations, Lix will guess the URL that was used in the derivation using the url or urls properties in the derivation environment. This is a layering violation but making these diagnostics tractable when there are multiple instances of the AAAA hash is too significant of an improvement to pass it up.

error: hash mismatch in fixed-output derivation '/nix/store/sjfw324j4533lwnpmr5z4icpb85r63ai-x1.drv':
        likely URL: https://meow.puppy.forge/puppy.tar.gz
         specified: sha256-AAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAAA=
            got:    sha256-a1Qvp3FOOkWpL9kFHgugU1ok5UtRPSu+NwCZKbbaEro=