tests.splicing: add

pkgs/test/default.nix

@@ -49,6 +49,8 @@ with pkgs;
 
   cross = callPackage ./cross {};
 
+  splicing = callPackage ./splicing {};
+
   php = recurseIntoAttrs (callPackages ./php {});
 
   pkg-config = recurseIntoAttrs (callPackage ../top-level/pkg-config/tests.nix { });

pkgs/test/splicing/default.nix

@@ -0,0 +1,40 @@
+{ pkgs, stdenvNoCC, lib, }:
+let
+  pkgsCross = pkgs.pkgsCross.aarch64-multiplatform.__splicedPackages;
+  tests =
+    let
+      pythonInNativeBuildInputs = lib.elemAt pkgsCross.python3Packages.xpybutil.nativeBuildInputs 0;
+      overridenAttr = pkgsCross.hello.overrideAttrs (_: { something = "hello"; });
+    in
+    [
+      ({
+        name = "pythonInNativeBuildInputsShouldBeNative";
+        expr = pythonInNativeBuildInputs.stdenv.hostPlatform.system == "x86_64-linux";
+        expected = true;
+      })
+      ({
+        name = "overridenAttrShouldHaveSplicedAndSomething";
+        expr = if overridenAttr ? __spliced then overridenAttr.something == overridenAttr.__spliced.buildHost.something else false;
+        expected = true;
+      })
+      ({
+        name = "splicedShouldBeOverriden";
+        expr = pkgsCross.nix.aws-sdk-cpp.cmakeFlags == pkgsCross.nix.aws-sdk-cpp.__spliced.hostTarget.cmakeFlags;
+        expected = true;
+      })
+      ({
+        name = "notCrossOverriden";
+        expr = (pkgs.hello.overrideAttrs (_: _: { passthru = { o = "works"; }; })) ? o;
+        expected = true;
+      })
+    ];
+in
+{
+  test-splicing = stdenvNoCC.mkDerivation {
+    name = "test-splicing";
+    passthru = { inherit tests; };
+    buildCommand = ''
+      touch $out
+    '' + lib.concatMapStringsSep "\n" (t: "([[ ${lib.boolToString t.expr} == ${lib.boolToString t.expected} ]] && echo '${t.name} success') || (echo '${t.name} fail' && exit 1)") tests;
+  };
+}