check-meta: Avoid expensive evaluation of output meta

Thanks for the pointer @llakala!

Author: infinisil

pkgs/stdenv/generic/check-meta.nix

@@ -52,7 +52,7 @@ let
     problemsType
     genCheckProblems
     ;
-  checkProblems = genCheckProblems config;
+  checkProblems = genCheckProblems config defaultRequiresMaintainers;
 
   # If we're in hydra, we can dispense with the more verbose error
   # messages and make problems easier to spot.
@@ -749,10 +749,14 @@ let
     let
       checkValidity' = checkValidity hostPlatform;
     in
-    { meta, attrs }:
+    {
+      meta,
+      attrs,
+      pos ? null,
+    }:
     let
       invalid = checkValidity' attrs;
-      problems = checkProblems attrs meta;
+      problems = checkProblems attrs pos;
     in
     if isNull invalid then
       if isNull problems then

pkgs/stdenv/generic/make-derivation.nix

@@ -980,7 +980,7 @@ let
           ++ attrs.propagatedNativeBuildInputs or [ ]
           ++ attrs.propagatedBuildInputs or [ ];
       };
-      validity = assertValidity { inherit meta attrs; };
+      validity = assertValidity { inherit meta attrs pos; };
 
       checkedEnv =
         let

pkgs/stdenv/generic/problems.nix

@@ -96,8 +96,8 @@ rec {
     {
       kindName = "maintainerless";
       condition =
-        config: attrs: outputMeta:
-        outputMeta.requiresMaintainers
+        config: attrs: requiresMaintainers:
+        requiresMaintainers
         && (attrs.meta.maintainers or [ ] == [ ])
         && (attrs.meta.teams or [ ] == [ ])
         && (attrs.meta.hasNoMaintainersButDependents or false == false);
@@ -117,20 +117,20 @@ rec {
               config.allowBrokenPredicate;
         in
         if allowBroken then
-          attrs: outputMeta: false
+          attrs: requiresMaintainers: false
         else if config ? allowBrokenPredicate then
-          attrs: outputMeta: attrs ? meta.broken && attrs.meta.broken && !allowBrokenPredicate attrs
+          attrs: requiresMaintainers: attrs ? meta.broken && attrs.meta.broken && !allowBrokenPredicate attrs
         else
-          attrs: outputMeta: attrs ? meta.broken && attrs.meta.broken;
+          attrs: requiresMaintainers: attrs ? meta.broken && attrs.meta.broken;
       value.message = "This package is broken.";
     }
   ];
 
   genAutomaticProblems =
-    config: attrs: outputMeta:
+    config: attrs: requiresMaintainers:
     listToAttrs (
       map (problem: lib.nameValuePair problem.kindName problem.value) (
-        filter (problem: problem.condition config attrs outputMeta) automaticProblems
+        filter (problem: problem.condition config attrs requiresMaintainers) automaticProblems
       )
     );
 
@@ -446,7 +446,7 @@ rec {
     };
 
   genCheckProblems =
-    config:
+    config: defaultRequiresMaintainers:
     let
       # This is here so that it gets cached for a (checkProblems config) thunk
       inherit (genHandlerSwitch config)
@@ -468,11 +468,14 @@ rec {
         }
       ) automaticProblems;
     in
-    attrs: outputMeta:
+    attrs: pos:
+    let
+      requiresMaintainers = attrs.meta.requiresMaintainers or (defaultRequiresMaintainers attrs pos);
+    in
     if
       # Fast path for when there's no problem that needs to be handled
       all (
-        problem: problem.condition attrs outputMeta -> problem.handler (getName attrs) == "ignore"
+        problem: problem.condition attrs requiresMaintainers -> problem.handler (getName attrs) == "ignore"
       ) automaticProblemsConfigCache
       && (
         # No manual problems
@@ -488,7 +491,7 @@ rec {
       # Slow path, only here we actually figure out which problems we need to handle
       let
         pname = getName attrs;
-        problems = attrs.meta.problems or { } // genAutomaticProblems config attrs outputMeta;
+        problems = attrs.meta.problems or { } // genAutomaticProblems config attrs requiresMaintainers;
         problemsToHandle = filter (v: v.handler != "ignore") (
           mapAttrsToList (name: problem: rec {
             inherit name;