haskellPackages.callPackage: preserve functionArgs (#443442)

pkgs/development/haskell-modules/make-package-set.nix

@@ -107,29 +107,35 @@ let
       # is that nix has no way to "passthrough" args while preserving the reflection
       # info that callPackage uses to determine the arguments).
       drv = if lib.isFunction fn then fn else import fn;
-      auto = builtins.intersectAttrs (lib.functionArgs drv) scope;
+      drvFunctionArgs = lib.functionArgs drv;
+      auto = builtins.intersectAttrs drvFunctionArgs scope;
 
       # Converts a returned function to a functor attribute set if necessary
       ensureAttrs = v: if builtins.isFunction v then { __functor = _: v; } else v;
 
       # this wraps the `drv` function to add `scope` and `overrideScope` to the result.
-      drvScope =
+      # it's a functor, so that we can pass through `functionArgs`
-        allArgs:
+      drvScope = {
-        ensureAttrs (drv allArgs)
+        __functor =
-        // {
+          _: allArgs:
-          inherit scope;
+          ensureAttrs (drv allArgs)
-          overrideScope =
+          // {
-            f:
+            inherit scope;
-            let
+            overrideScope =
-              newScope = mkScope (fix' (extends f scope.__unfix__));
+              f:
-            in
+              let
-            # note that we have to be careful here: `allArgs` includes the auto-arguments that
+                newScope = mkScope (fix' (extends f scope.__unfix__));
-            # weren't manually specified. If we would just pass `allArgs` to the recursive call here,
+              in
-            # then we wouldn't look up any packages in the scope in the next interation, because it
+              # note that we have to be careful here: `allArgs` includes the auto-arguments that
-            # appears as if all arguments were already manually passed, so the scope change would do
+              # weren't manually specified. If we would just pass `allArgs` to the recursive call here,
-            # nothing.
+              # then we wouldn't look up any packages in the scope in the next interation, because it
-            callPackageWithScope newScope drv manualArgs;
+              # appears as if all arguments were already manually passed, so the scope change would do
-        };
+              # nothing.
+              callPackageWithScope newScope drv manualArgs;
+          };
+        # `drvScope` accepts the same arguments as `drv`
+        __functionArgs = drvFunctionArgs;
+      };
     in
     lib.makeOverridable drvScope (auto // manualArgs);