Method action

lib/command.js:557–573

* Register callback `fn` for the command. * * @example * program * .command('serve') * .description('start service') * .action(function() { * // do work here * }); * * @param {Function} fn * @return {Command} `this` command for chaining

(fn)

   */

  action(fn) {
    const listener = (args) => {
      // The .action callback takes an extra parameter which is the command or options.
      const expectedArgsCount = this.registeredArguments.length;
      const actionArgs = args.slice(0, expectedArgsCount);
      if (this._storeOptionsAsProperties) {
        actionArgs[expectedArgsCount] = this; // backwards compatible "options"
      } else {
        actionArgs[expectedArgsCount] = this.opts();
      }
      actionArgs.push(this);

      return fn.apply(this, actionArgs);
    };
    this._actionHandler = listener;
    return this;
  }

  /**
   * Factory routine to create a new unattached option.