检查重复项无法正常工作的功能

Question

I have this mini app that allows the user to enter the make and model of a car, then adds it to the table below. I have added a function that will check for duplicates and alert if there are any already existing in the table. If there are no existing records that match, it will push the new "make" and "model" to the table. I changed the code to use _.isEqual instead of what I had prior and now it gets caught at the Alert every time I run it. Anyone know what is going on?

 <div>Make: <input type="text" ng-model="make"></div>
 <div>Model:<input type="text" ng-model="model"></div>
 <button ng-click="add()">Add</button>

    <tr>
        <th>Make</th>
        <th>Model</th>
    </tr>
    <tr ng-repeat="car in cars" ng-click="rowClick(car)">
        <td>{{car.make}}</td>
        <td>{{car.model}}</td>
    </tr>

 var carsApp = angular.module('carsApp', []);

carsApp.controller('carController', function ($scope){

   $scope.cars = [];

  $scope.add = function () {

      var newCar = {
        make: $scope.make,
        model: $scope.model
      };

      function hasDuplicates(){
        angular.forEach($scope.cars, function(car, key){
          _.isEqual(car, newCar);
        });
      }

      if (hasDuplicates) {
          alert("Car already exists");
          } else {  
           $scope.cars.push(newCar);
          }
      }      

      $scope.rowClick = function(car){
          $scope.make= car.make;
          $scope.model= car.model;
      };

        $scope.make = null;
        $scope.model = null;

  });

Answer 1

Ended up going with a simpler option and used angular.equals instead. isEqual was too much of a pain to implement properly. Thanks for all the help!

function hasDuplicates(newCar){
     var returnVal = false;
     angular.forEach($scope.cars, function(car, key){
        if (angular.equals(car, newCar))
        {
          returnVal = true;
        }
      });
     return returnVal;
  };