1 files changed, 14 insertions, 0 deletions
diff --git a/dom/bindings/parser/tests/test_double_null.py b/dom/bindings/parser/tests/test_double_null.py
new file mode 100644
index 000000000..700c7eade
--- /dev/null
+++ b/dom/bindings/parser/tests/test_double_null.py
@@ -0,0 +1,14 @@
+def WebIDLTest(parser, harness):
+    threw = False
+    try:
+        parser.parse("""
+            interface DoubleNull {
+              attribute byte?? foo;
+            };
+        """)
+
+        results = parser.finish()
+    except:
+        threw = True
+
+    harness.ok(threw, "Should have thrown.")