Add a test.
diff --git a/resources/test/tests/unit/IdlInterface/constructors.html b/resources/test/tests/unit/IdlInterface/constructors.html
new file mode 100644
index 0000000..93cc7f4
--- /dev/null
+++ b/resources/test/tests/unit/IdlInterface/constructors.html
@@ -0,0 +1,25 @@
+<!DOCTYPE HTML>
+<title>IdlInterface.prototype.constructors()</title>
+<div id="log"></div>
+<script src="/resources/testharness.js"></script>
+<script src="/resources/testharnessreport.js"></script>
+<script src="/resources/WebIDLParser.js"></script>
+<script src="/resources/idlharness.js"></script>
+<script src="../../../idl-helper.js"></script>
+<script>
+"use strict";
+test(function() {
+ var i = interfaceFrom('[Constructor] interface A { };');
+ assert_equals(i.constructors().length, 1);
+}, 'Interface with Constructor extended attribute.');
+
+test(function() {
+ var i = interfaceFrom('interface A { constructor(); };');
+ assert_equals(i.constructors().length, 1);
+}, 'Interface with constructor method');
+
+test(function() {
+ var i = interfaceFrom('[Constructor] interface A { constructor(); };');
+ assert_equals(i.constructors().length, 2);
+}, 'Interface with both');
+</script>
