std::vector<Status> statuses;
  EXPECT_FALSE(env_->FilesExist(filenames, &statuses));
  EXPECT_EQ(statuses.size(), filenames.size());
  EXPECT_PRED2(UnimplementedOrReturnsCode, statuses[0], Code::OK);
  EXPECT_PRED2(UnimplementedOrReturnsCode, statuses[1], Code::OK);
  EXPECT_PRED2(UnimplementedOrReturnsCode, statuses[2],
               Code::FAILED_PRECONDITION);

  ///   * `paths` has exactly `num_files` entries.
  ///   * `statuses` is either null or an array of `num_files` non-null elements
  ///     of type `TF_Status*`.
  ///
  /// If `statuses` is not null, plugins must fill each element with detailed
  /// status for each file, as if calling `path_exists` on each one. Core
  /// TensorFlow initializes the `statuses` array and plugins must use