throw new InvalidDefinitionException(String.format(
"%s cannot extend non-extensible component %s", getDescriptor(), extendsDescriptor),
getLocation());
}
registry.assertAccess(descriptor, parentDef);
SupportLevel support = getSupport();
DefDescriptor<T> extDesc = extendsDescriptor;
while (extDesc != null) {
T extDef = extDesc.getDef();