michael@0: def WebIDLTest(parser, harness):
michael@0:     threw = False
michael@0:     try:
michael@0:         parser.parse("""
michael@0:             interface OptionalConstraints1 {
michael@0:               void foo(optional byte arg1, byte arg2);
michael@0:             };
michael@0:         """)
michael@0: 
michael@0:         results = parser.finish()
michael@0:     except:
michael@0:         threw = True
michael@0: 
michael@0:     harness.ok(not threw,
michael@0:                "Should not have thrown on non-optional argument following "
michael@0:                "optional argument.")
michael@0: 
michael@0:     parser = parser.reset()
michael@0:     parser.parse("""
michael@0:         interface OptionalConstraints2 {
michael@0:           void foo(optional byte arg1 = 1, optional byte arg2 = 2,
michael@0:                    optional byte arg3, optional byte arg4 = 4,
michael@0:                    optional byte arg5, optional byte arg6 = 9);
michael@0:         };
michael@0:     """)
michael@0:     results = parser.finish()
michael@0:     args = results[0].members[0].signatures()[0][1]
michael@0:     harness.check(len(args), 6, "Should have 6 arguments")
michael@0:     harness.check(args[5].defaultValue.value, 9,
michael@0:                   "Should have correct default value")