Breaking change in crane fails Hydra CI

[jpraynaud]

Why

We have noticed that the Hydra CI fails when we update nix flake with the command nix flake update.

It raises this error: (https://github.com/input-output-hk/mithril/runs/29720308582)

hydra-eval-jobs returned exit code 1:
warning: ignoring --gc-roots-dir (just supported for compatibility)
info: waiting for evaluation...
info: evaluation failed
error:
       … while calling anonymous lambda

         at «string»:68:1:

           67| };
           68| flake: let
             | ^
           69|   job = let

       … from call site

         at «string»:128:20:

          127|
          128|     jobAttrPaths = lib.collectAttrPaths lib.isDerivation jobAttrs;
             |                    ^
          129|   in

       … while calling 'collectAttrPaths'

         at «string»:20:33:

           19|
           20|   collectAttrPaths = predicate: attrs: let
             |                                 ^
           21|     internal = path: attrs: let

       … from call site

         at «string»:53:5:

           52|   in
           53|     internal [] attrs;
             |     ^
           54|

       … while calling 'internal'

         at «string»:21:22:

           20|   collectAttrPaths = predicate: attrs: let
           21|     internal = path: attrs: let
             |                      ^
           22|       inherit

       … from call site

         at «string»:36:11:

           35|         then
           36|           flattenDepth 1 (
             |           ^
           37|             map

       … while calling 'flattenDepth'

         at «string»:6:25:

            5|
            6|   flattenDepth = depth: x:
             |                         ^
            7|     if builtins.isList x && (depth == null || depth >= 0)

       … while calling 'flattenDepth'

         at «string»:6:25:

            5|
            6|   flattenDepth = depth: x:
             |                         ^
            7|     if builtins.isList x && (depth == null || depth >= 0)

       … while calling anonymous lambda

         at «string»:39:15:

           38|             (
           39|               attrName:
             |               ^
           40|                 internal

       … from call site

         at «string»:40:17:

           39|               attrName:
           40|                 internal
             |                 ^
           41|                 (path ++ [attrName])

       … while calling 'internal'

         at «string»:21:22:

           20|   collectAttrPaths = predicate: attrs: let
           21|     internal = path: attrs: let
             |                      ^
           22|       inherit

       … while calling anonymous lambda

         at «string»:25:12:

           24|           builtins.partition
           25|           (attrName: predicate attrs.${attrName})
             |            ^
           26|           (builtins.attrNames attrs)

       … from call site

         at «string»:25:22:

           24|           builtins.partition
           25|           (attrName: predicate attrs.${attrName})
             |                      ^
           26|           (builtins.attrNames attrs)

       … while calling 'isDerivation'

         at «string»:4:18:

            3|   # copied from nixpkgs
            4|   isDerivation = value: value.type or null == "derivation";
             |                  ^
            5|

       … while calling anonymous lambda

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/types.nix:607:29:

          606|       merge = loc: defs:
          607|         zipAttrsWith (name: defs:
             |                             ^
          608|           let merged = mergeDefinitions (loc ++ [name]) elemType defs;

       … while calling anonymous lambda

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/modules.nix:836:28:

          835|         # Process mkMerge and mkIf properties.
          836|         defs' = concatMap (m:
             |                            ^
          837|           map (value: { inherit (m) file; inherit value; }) (addErrorContext "while evaluating definitions from `${m.file}':" (dischargeProperties m.value))

       … while evaluating definitions from `/nix/store/8ql43f4sxqh1dbpqy2q5jz11zdwf9832-source/modules/transposition.nix':

       … from call site

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/modules.nix:837:128:

          836|         defs' = concatMap (m:
          837|           map (value: { inherit (m) file; inherit value; }) (addErrorContext "while evaluating definitions from `${m.file}':" (dischargeProperties m.value))
             |                                                                                                                                ^
          838|         ) defs;

       … while calling 'dischargeProperties'

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/modules.nix:908:25:

          907|   */
          908|   dischargeProperties = def:
             |                         ^
          909|     if def._type or "" == "merge" then

       … while calling anonymous lambda

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/types.nix:607:29:

          606|       merge = loc: defs:
          607|         zipAttrsWith (name: defs:
             |                             ^
          608|           let merged = mergeDefinitions (loc ++ [name]) elemType defs;

       … while calling anonymous lambda

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/modules.nix:836:28:

          835|         # Process mkMerge and mkIf properties.
          836|         defs' = concatMap (m:
             |                            ^
          837|           map (value: { inherit (m) file; inherit value; }) (addErrorContext "while evaluating definitions from `${m.file}':" (dischargeProperties m.value))

       … while evaluating definitions from `/nix/store/2nixq6l4bpcx48xl99ixdfxk7fjyd6m6-source/flake.nix, via option perSystem':

       … from call site

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/modules.nix:837:128:

          836|         defs' = concatMap (m:
          837|           map (value: { inherit (m) file; inherit value; }) (addErrorContext "while evaluating definitions from `${m.file}':" (dischargeProperties m.value))
             |                                                                                                                                ^
          838|         ) defs;

       … while calling 'dischargeProperties'

         at /nix/store/fkjds639pw6ykj3zib7cp4y9i9h6ka9w-source/modules.nix:908:25:

          907|   */
          908|   dischargeProperties = def:
             |                         ^
          909|     if def._type or "" == "merge" then

       … from call site

         at /nix/store/2nixq6l4bpcx48xl99ixdfxk7fjyd6m6-source/flake.nix:101:19:

          100|         mithril-common = buildPackage ./mithril-common/Cargo.toml mithril-stm.cargoArtifacts { cargoExtraArgs = "-p mithril-common --features full"; };
          101|         mithril = buildPackage null mithril-common.cargoArtifacts {
             |                   ^
          102|           doCheck = false;

       … while calling 'buildPackage'

         at /nix/store/2nixq6l4bpcx48xl99ixdfxk7fjyd6m6-source/flake.nix:88:55:

           87|
           88|         buildPackage = cargoToml: baseCargoArtifacts: args:
             |                                                       ^
           89|           craneLib.buildPackage (commonsArgs

       error: attribute 'lib' missing

       at /nix/store/2nixq6l4bpcx48xl99ixdfxk7fjyd6m6-source/flake.nix:26:20:

           25|         inherit (inputs.nixpkgs) lib;
           26|         craneLib = inputs.crane.lib.${system};
             |                    ^
           27|

What

Fix the issue with a quick fix and a long term fix by adapting the implementation to the breaking changes of crane.

How

• Quick fix the nix configuration to target the latest version we support (0.18)
• Long term fix by adapting the nix configuration to the latest version of crane