@Test
public void updateDriveFileWithSyncStateWithoutIdentifier() throws Exception {

    final java.io.File file = new java.io.File("/");
    when(currentSyncState.getSyncId(SyncProvider.GoogleDrive)).thenReturn(null);
    final TestObserver<SyncState> testObserver = driveStreamsManager.updateDriveFile(currentSyncState, file).test();
    testObserver.assertNoValues();
    testObserver.assertNotComplete();
    testObserver.assertError(Exception.class);
    verify(driveErrorStream).onNext(Optional.of(criticalSyncError));
}