AttributeRegistrar { void addPendingMutations(@NonNull List<AttributeMutation> mutations) { mutationStore.add(mutations); } AttributeRegistrar(AttributeApiClient apiClient, PendingAttributeMutationStore mutationStore);   }
@Test public void testAdd() { AttributeMutation mutation = AttributeMutation.newSetAttributeMutation("expected_key", JsonValue.wrapOpt("expected_value"), 100); List<AttributeMutation> pendingAttributeMutations = Collections.singletonList(mutation); registrar.addPendingMutations(pendingAttributeMutations); assertEquals(pendingAttributeMutations, store.peek()); }