bool MatchPath(const tsl::string& path, const tsl::string& pattern) override {
    return false;
  }

  void SleepForMicroseconds(int64_t micros) override {}

  tsl::string GetRunfilesDir() override { return tsl::string("dummy_path"); }

  int32_t GetCurrentThreadId() override { return 0; }

  tsl::Thread* StartThread(const tsl::ThreadOptions& thread_options,

  Env* env = Env::Default();
  std::string tfr_lib_dir;
  TF_RETURN_IF_ERROR(ReadStringFromEnvVar(
      kTFRLibEnv, "tensorflow/compiler/mlir/tfr/resources", &tfr_lib_dir));
  string composite_mlir_dir = io::JoinPath(env->GetRunfilesDir(), tfr_lib_dir);
  std::vector<string> files;
  TF_RETURN_IF_ERROR(env->GetChildren(composite_mlir_dir, &files));
  if (files.empty()) {
    return errors::Internal(absl::StrCat(