1 files changed, 18 insertions, 0 deletions
diff --git a/js/src/jit-test/tests/basic/emulates-undefined.js b/js/src/jit-test/tests/basic/emulates-undefined.js
new file mode 100644
index 0000000000..3e379d8746
--- /dev/null
+++ b/js/src/jit-test/tests/basic/emulates-undefined.js
@@ -0,0 +1,18 @@
+function test() {
+    var values = [undefined, null, Math, createIsHTMLDDA()];
+    var expected = [true, true, false, true];
+
+    for (var i=0; i<100; i++) {
+        var idx = i % values.length;
+        if (values[idx] == undefined)
+            assertEq(expected[idx], true);
+        else
+            assertEq(expected[idx], false);
+
+        if (null != values[idx])
+            assertEq(expected[idx], false);
+        else
+            assertEq(expected[idx], true);
+    }
+}
+test();