Function callbackAfter

test/util.js:33–38

(err)

    throw new Error('Required `callback` argument must be a function');
  }
  var callbackAfter = function(err) {
    callbackAfter.called++;
    if (err) return callback(err);
    if (callbackAfter.called <= calls) return;
    callback();
  };
  callbackAfter.called = 0;
  return callbackAfter;
};