@Test
public void should_not_migrate_file_which_are_not_json() throws Exception {

    Migration<Page> migration = mock(Migration.class);
    LiveRepositoryUpdate<Page> liveRepositoryUpdate = new LiveRepositoryUpdate<>(repository, loader, singletonList(migration));
    folder.newFile("whatever");
    liveRepositoryUpdate.migrate();
    verify(migration, never()).migrate(any(Page.class));
}