Work In Progress: Handle Maps and Sets in Structured Clone

LayoutTests/fast/js/structured-clone.html

Index: LayoutTests/fast/js/structured-clone.html
diff --git a/LayoutTests/fast/js/structured-clone.html b/LayoutTests/fast/js/structured-clone.html
index 6cd9c365878d5340ae30ced8ce4297c7a39f3dde..7d5ae25011b17ab6a0e3439c91a949240edf6cb0 100644
--- a/LayoutTests/fast/js/structured-clone.html
+++ b/LayoutTests/fast/js/structured-clone.html
@@ -119,4 +119,21 @@ promise_test(function() {
     });
 }, 'Verify: "Add a new property..." (dense arrays)');
 
+promise_test(function() {
+    var orig = {
+        emptySet: new Set,
+        set: new Set([1, 2, 3]),
+        emptyMap: new Map,
+        map: new Map([[1, 2], [3, 4]])
+    };
+    return structuredClone(orig).then(function(clone) {
+        assert_true(clone.emptySet instanceof Set, 'Clone should be a Set');
+        assert_true(clone.emptyMap instanceof Map, 'Clone should be a Map');
+        assert_true(clone.set instanceof Set, 'Clone should be a Set');
+        assert_true(clone.map instanceof Map, 'Clone should be a Map');
+        assert_equals(clone.set.size, orig.set.size, 'Clone should be the same size');
+        assert_equals(clone.map.size, orig.map.size, 'Clone should be the same size');
+    });
+}, 'Verify: "Maps and Sets are cloned..."');
+
 </script>