code: function yarn(cmds, args, cb) {
    if (typeof args === 'function') {
      return yarn(cmds, [], args);
    }
  
    args = arrayify(cmds).concat(arrayify(args));
    spawn('yarn', args, {cwd: cwd, stdio: 'inherit'})
      .on('error', cb)
      .on('close', function(code, err) {
        cb(err, code);
      });
  }
docs: Run `yarn` with the given `cmds`, `args` and callback.
  
  ```js
  yarn(['add', 'isobject'], function(err) {
  if (err) throw err;
  });
  ```
  @param {String|Array} `cmds`
  @param {String|Array} `args`
  @param {Function} `cb` Callback
  @details false
  @api public