this derivation will be built:
  /nix/store/rs327fghwky70idddplp1x21jb5w1s7f-treefmt-check.drv
error: Cannot build '/nix/store/rs327fghwky70idddplp1x21jb5w1s7f-treefmt-check.drv'.
       Reason: builder failed with exit code 1.
       Output paths:
         /nix/store/kw5zr0ia4s67bc0s4ly2ycsxyb73ly3n-treefmt-check
       Last 25 log lines:
       > -        assert!(expr.contains("f ? legacyPackages"), "missing legacyPackages branch: {expr}");
       > +        assert!(
       > +            expr.contains("f ? foo.unwrapped"),
       > +            "missing top-level check: {expr}"
       > +        );
       > +        assert!(
       > +            expr.contains("f ? packages"),
       > +            "missing packages branch: {expr}"
       > +        );
       > +        assert!(
       > +            expr.contains("f ? legacyPackages"),
       > +            "missing legacyPackages branch: {expr}"
       > +        );
       >          // A fully-qualified path works the same way; f ? packages.x86_64-linux.samba
       >          // will succeed in branch 1 so branches 2 and 3 are never reached.
       > -        let expr2 = build_flake_expression("/nix/store/x", "sha256-abc", "packages.x86_64-linux.samba");
       > -        assert!(expr2.contains("f ? packages.x86_64-linux.samba"), "missing top-level check: {expr2}");
       > +        let expr2 =
       > +            build_flake_expression("/nix/store/x", "sha256-abc", "packages.x86_64-linux.samba");
       > +        assert!(
       > +            expr2.contains("f ? packages.x86_64-linux.samba"),
       > +            "missing top-level check: {expr2}"
       > +        );
       >      }
       >  }
       For full logs, run:
         nix log /nix/store/rs327fghwky70idddplp1x21jb5w1s7f-treefmt-check.drv