1 files changed, 33 insertions, 26 deletions
diff --git a/third_party/overlays/haskell/default.nix b/third_party/overlays/haskell/default.nix
index 975918803e29..7b17e61e3e02 100644
--- a/third_party/overlays/haskell/default.nix
+++ b/third_party/overlays/haskell/default.nix
@@ -1,34 +1,41 @@
-# Defines overrides for Haskell packages, for example to avoid
-# breakage currently present in nixpkgs or to modify package versions.
+# Defines an overlay for overriding Haskell packages, for example to
+# avoid breakage currently present in nixpkgs or to modify package
+# versions.
 
 { ... }: # This file needs nothing from readTree
-{ pkgs }: # ... but is called with a separate package set in the overlay
 
-self: super: with pkgs.haskell.lib; rec {
-  generic-arbitrary = appendPatch
-    super.generic-arbitrary
-    [ ./patches/generic-arbitrary-export-garbitrary.patch ];
+self: super: # overlay parameters for the nixpkgs overlay
 
-  random = dontCheck (self.callHackageDirect {
-    pkg = "random";
-    ver = "1.2.0";
-    sha256 = "06s3mmqbsfwv09j2s45qnd66nrxfp9280gnl9ng8yh128pfr7bjh";
-  } {});
+let
+  overrides = hsSelf: hsSuper: with super.haskell.lib; rec {
+    generic-arbitrary = appendPatch hsSuper.generic-arbitrary
+      [ ./patches/generic-arbitrary-export-garbitrary.patch ];
 
-  # random <1.2
-  test-framework = doJailbreak super.test-framework;
-  hashable = doJailbreak super.hashable;
-  test-framework-quickcheck2 = doJailbreak super.test-framework-quickcheck2;
+    # random = dontCheck (hsSuper.callHackageDirect {
+    #   pkg = "random";
+    #   ver = "1.2.0";
+    #   sha256 = "06s3mmqbsfwv09j2s45qnd66nrxfp9280gnl9ng8yh128pfr7bjh";
+    # } {});
 
-  # can be removed if we have the following PR or equivalent
-  # https://github.com/NixOS/nixpkgs/pull/116931
-  hedgehog-classes = overrideCabal super.hedgehog-classes (attrs: {
-    # remove version bound on semirings which is inside a
-    # conditional, so doJailbreak doesn't work
-    prePatch = ''
-      sed -i 's|semirings.*0.6|semirings|g' hedgehog-classes.cabal
-    '';
-  });
+    # random <1.2
+    test-framework = doJailbreak hsSuper.test-framework;
+    hashable = doJailbreak hsSuper.hashable;
+    test-framework-quickcheck2 = doJailbreak hsSuper.test-framework-quickcheck2;
 
-  hgeometry-combinatorial = dontCheck super.hgeometry-combinatorial;
+    # can be removed if we have the following PR or equivalent
+    # https://github.com/NixOS/nixpkgs/pull/116931
+    hedgehog-classes = overrideCabal hsSuper.hedgehog-classes (attrs: {
+      # remove version bound on semirings which is inside a
+      # conditional, so doJailbreak doesn't work
+      prePatch = ''
+        sed -i 's|semirings.*0.6|semirings|g' hedgehog-classes.cabal
+      '';
+    });
+
+    hgeometry-combinatorial = dontCheck hsSuper.hgeometry-combinatorial;
+  };
+in {
+  haskellPackages = super.haskellPackages.override {
+    inherit overrides;
+  };
 }