diff --git a/pkgs/build-support/src-only/tests.nix b/pkgs/build-support/src-only/tests.nix
index d00a2060703e..f739715e717d 100644
--- a/pkgs/build-support/src-only/tests.nix
+++ b/pkgs/build-support/src-only/tests.nix
@@ -1,4 +1,5 @@
 {
+  lib,
   runCommand,
   srcOnly,
   hello,
@@ -32,16 +33,26 @@ let
       ;
   };
   helloDrvSimpleSrc = srcOnly helloDrvSimple;
-  helloDrvSimpleSrcFreeform = srcOnly {
-    inherit (helloDrvSimple)
-      name
-      pname
-      version
-      src
-      patches
-      stdenv
-      ;
-  };
+  helloDrvSimpleSrcFreeform = srcOnly (
+    {
+      inherit (helloDrvSimple)
+        name
+        pname
+        version
+        src
+        patches
+        stdenv
+        ;
+    }
+    # __impureHostDeps get duplicated in helloDrvSimpleSrc (on darwin)
+    # This is harmless, but fails the test for what is arguably an
+    # unrelated non-problem, so we just work around it here.
+    # The inclusion of __impureHostDeps really shouldn't be required,
+    # and should be removed from this test.
+    // lib.optionalAttrs (helloDrvSimple ? __impureHostDeps) {
+      inherit (helloDrvSimple) __impureHostDeps;
+    }
+  );
 
 in