Method #watchFile

lib/internal/fs/recursive_watch.js:169–220

(file)

  }

  #watchFile(file) {
    if (this.#closed) {
      return;
    }

    const { watch, statSync } = lazyLoadFsSync();

    if (this.#files.has(file)) {
      return;
    }

    {
      const existingStat = statSync(file);
      this.#files.set(file, existingStat);
    }

    const watcher = watch(file, {
      persistent: this.#options.persistent,
    }, (eventType, filename) => {
      const existingStat = this.#files.get(file);
      let currentStats;

      try {
        currentStats = statSync(file);
        this.#files.set(file, currentStats);
      } catch {
        // This happens if the file was removed
      }

      if (currentStats === undefined || (currentStats.birthtimeMs === 0 && existingStat.birthtimeMs !== 0)) {
        // The file is now deleted
        this.#files.delete(file);
        this.#watchers.delete(file);
        watcher.close();
        this.emit('change', 'rename', pathRelative(this.#rootPath, file));
        this.#unwatchFiles(file);
      } else if (file === this.#rootPath && this.#watchingFile) {
        // This case will only be triggered when watching a file with fs.watch
        this.emit('change', 'change', pathBasename(file));
      } else if (this.#symbolicFiles.has(file)) {
        // Stats from watchFile does not return correct value for currentStats.isSymbolicLink()
        // Since it is only valid when using fs.lstat(). Therefore, check the existing symbolic files.
        this.emit('change', 'rename', pathRelative(this.#rootPath, file));
      } else if (currentStats.isDirectory()) {
        this.#watchFolder(file);
      } else {
        // Watching a directory will trigger a change event for child files)
        this.emit('change', 'change', pathRelative(this.#rootPath, file));
      }
    });
    this.#watchers.set(file, watcher);
  }

  [kFSWatchStart](filename) {
    filename = pathResolve(getValidatedPath(filename));