unit testing $('#modalId').modal('show'); undefined

Question

I am new to unit testing as well as in angularjs.

When I unit test my modal if they are showing or not, an error was returned:

> TypeError: undefined is not a constructor (evaluating
> '$('#modalId').modal('show')')

How can I unit test my modals ?

Answer 1

It depends on what testing framework you are using. In case of jasmine you can spy on modal. Lets say you have this controller:

'use strict';

angular.module('angularUiModalApp')
    .controller('MainCtrl', function($scope, $modal, $log) {
        $scope.items = ['item1', 'item2', 'item3'];

        $scope.open = function() {

            $scope.modalInstance = $modal.open({
                templateUrl: 'myModalContent.html',
                controller: 'ModalInstanceCtrl',
                resolve: {
                    items: function() {
                        return $scope.items;
                    }
                }
            });

            $scope.modalInstance.result.then(function(selectedItem) {
                $scope.selected = selectedItem;
            }, function() {
                $log.info('Modal dismissed at: ' + new Date());
            });
        };
    })
    .controller('ModalInstanceCtrl', function($scope, $modalInstance, items) {
        $scope.items = items;
        $scope.selected = {
            item: $scope.items[0]
        };

        $scope.ok = function() {
            $modalInstance.close($scope.selected.item);
        };

        $scope.cancel = function() {
            $modalInstance.dismiss('cancel');
        };
    });

Then the test looks like this:

'use strict';

describe('Controller: MainCtrl', function() {

    // load the controller's module
    beforeEach(module('angularUiModalApp'));

    var MainCtrl,
        scope;

    var fakeModal = {
        result: {
            then: function(confirmCallback, cancelCallback) {
                //Store the callbacks for later when the user clicks on the OK or Cancel button of the dialog
                this.confirmCallBack = confirmCallback;
                this.cancelCallback = cancelCallback;
            }
        },
        close: function( item ) {
            //The user clicked OK on the modal dialog, call the stored confirm callback with the selected item
            this.result.confirmCallBack( item );
        },
        dismiss: function( type ) {
            //The user clicked cancel on the modal dialog, call the stored cancel callback
            this.result.cancelCallback( type );
        }
    };

    beforeEach(inject(function($modal) {
        spyOn($modal, 'open').andReturn(fakeModal);
    }));


    // Initialize the controller and a mock scope
    beforeEach(inject(function($controller, $rootScope, _$modal_) {
        scope = $rootScope.$new();
        MainCtrl = $controller('MainCtrl', {
            $scope: scope,
            $modal: _$modal_
        });
    }));

    it('should show success when modal login returns success response', function() {
        expect(scope.items).toEqual(['item1', 'item2', 'item3']);

        // Mock out the modal closing, resolving with a selected item, say 1
        scope.open(); // Open the modal
        scope.modalInstance.close('item1');
        expect(scope.selected).toEqual('item1'); 
        // No dice (scope.selected) is not defined according to Jasmine.
    });
});

You need to return a mock of what $modal.open normally returns, not a mock of $modal, which doesn’t include an open function is laid out in fakeModal mock. The fake modal must have a result object that contains a then function to store the callbacks (to be called when the OK or Cancel buttons are clicked on). It also needs a close function (simulating an OK button click on the modal) and a dismiss function (simulating a Cancel button click on the modal). The close and dismiss functions call the necessary call back functions when called.