michael@0: def WebIDLTest(parser, harness):
michael@0:     threw = False
michael@0:     try:
michael@0:         parser.parse("""
michael@0:             interface OneNullableInUnion {
michael@0:               void foo((object? or DOMString?) arg);
michael@0:             };
michael@0:         """)
michael@0: 
michael@0:         results = parser.finish()
michael@0:     except:
michael@0:         threw = True
michael@0: 
michael@0:     harness.ok(threw,
michael@0:                "Two nullable member types of a union should have thrown.")
michael@0: 
michael@0:     parser.reset()
michael@0:     threw = False
michael@0: 
michael@0:     try:
michael@0:         parser.parse("""
michael@0:             interface NullableInNullableUnion {
michael@0:               void foo((object? or DOMString)? arg);
michael@0:             };
michael@0:         """)
michael@0: 
michael@0:         results = parser.finish()
michael@0:     except:
michael@0:         threw = True
michael@0: 
michael@0:     harness.ok(threw,
michael@0:                "A nullable union type with a nullable member type should have "
michael@0:                "thrown.")
michael@0: 
michael@0:     parser.reset()
michael@0:     threw = False
michael@0: 
michael@0:     try:
michael@0:         parser.parse("""
michael@0:             interface NullableInUnionNullableUnionHelper {
michael@0:             };
michael@0:             interface NullableInUnionNullableUnion {
michael@0:               void foo(((object? or DOMString) or NullableInUnionNullableUnionHelper)? arg);
michael@0:             };
michael@0:         """)
michael@0: 
michael@0:         results = parser.finish()
michael@0:     except:
michael@0:         threw = True
michael@0: 
michael@0:     harness.ok(threw,
michael@0:                "A nullable union type with a nullable member type should have "
michael@0:                "thrown.")