@CheckForNull
  public FileData fileData(String moduleKeyWithBranch, String path) {
    SingleProjectRepository repository = repositoriesPerModule.get(moduleKeyWithBranch);
    return repository == null ? null : repository.fileData(path);
  }
@Test
  public void test_file_data_when_module_does_not_exist() {
    FileData fileData = repository.fileData("unknown", "/Def.java");

    assertThat(fileData).isNull();
  }