Commit graph

8 commits

Author SHA1 Message Date
Maximilian Bosch 6905291daf
libcmd/installables: force re-evaluation of cached failures
I think that it's not very helpful to get "cached failures" in a wrong
`flake.nix`. This can be very confusing when debugging a Nix expression.
See for instance NixOS/nixpkgs#118115.

In fact, the eval cache allows a forced reevaluation which is used for
e.g. `nix eval`.

This change makes sure that this is the case for `nix build` as well. So
rather than

    λ ma27 [~/Projects/exp] → ../nix/outputs/out/bin/nix build -L --rebuild --experimental-features 'nix-command flakes'
    error: cached failure of attribute 'defaultPackage.x86_64-linux'

the evaluation of already-evaluated (and failed) attributes looks like
this now:

    λ ma27 [~/Projects/exp] → ../nix/outputs/out/bin/nix build -L --rebuild --experimental-features 'nix-command flakes'
    error: attribute 'hell' missing

           at /nix/store/mrnvi9ss8zn5wj6gpn4bcd68vbh42mfh-source/flake.nix:6:35:

                5|
                6|     packages.x86_64-linux.hello = nixpkgs.legacyPackages.x86_64-linux.hell;
                 |                                   ^
                7|
    (use '--show-trace' to show detailed location information)
2021-04-19 19:51:04 +02:00
Eelco Dolstra ad143c5b3b Shut up some clang warnings 2020-10-06 14:52:30 +02:00
Eelco Dolstra 3c75ddc16b nix build (and others): Force re-evaluation of cached errors
Fixes #3872.

This is a bit hacky. Ideally we would automatically re-evaluate the
failed attribute iff we need to print the error message (so in
commands like 'nix search' we wouldn't re-evaluate because we're
suppressing errors).
2020-08-07 14:47:23 +02:00
John Ericson 5ea817dace Merge remote-tracking branch 'upstream/master' into hash-always-has-type 2020-07-16 14:58:53 +00:00
Eelco Dolstra 50f13b06fb EvalCache: Store string contexts 2020-06-29 19:08:37 +02:00
Eelco Dolstra b681408879 Factor out EvalCache::forceDerivation() 2020-06-29 16:39:41 +02:00
Eelco Dolstra b4e23dcd9e nix search: Search legacyPackages recursively 2020-04-27 16:29:26 +02:00
Eelco Dolstra 42a12f9232 Move eval-cache.{cc,hh} 2020-04-20 13:14:59 +02:00
Renamed from src/libexpr/flake/eval-cache.hh (Browse further)