The unit test for displaying the modal with the ID 'modalId' returned an undefined value

Question

The unit test for displaying the modal with the ID 'modalId' returned an undefined value

Being a beginner in both unit testing and angularjs, I encountered an issue while trying to test if my modals are displaying correctly.

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

Could you please provide guidance on how to properly unit test my modals? Thank you!

javascript angularjs unit-testing jasmine chutzpah

Answer 1

Answer №1

It varies depending on the testing framework you are utilizing. If you are using jasmine, you have the capability to spy on modals. For instance, suppose 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');
        };
    });

Subsequently, the test will resemble 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 must provide a mock that replicates the typical return of $modal.open, rather than a mock of $modal itself which does not include an open function as depicted in the fakeModal mock. The fake modal needs to contain a result object with a then function to store the callbacks (to be executed upon clicking the OK or Cancel buttons). Additionally, it should have a close function (emulating an OK button click on the modal) and a dismiss function (emulating a Cancel button click on the modal). Both the close and dismiss functions trigger the respective callback functions when invoked.

Answer 2

It varies depending on the testing framework you are utilizing. If you are using jasmine, you have the capability to spy on modals. For instance, suppose 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');
        };
    });

Subsequently, the test will resemble 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 must provide a mock that replicates the typical return of $modal.open, rather than a mock of $modal itself which does not include an open function as depicted in the fakeModal mock. The fake modal needs to contain a result object with a then function to store the callbacks (to be executed upon clicking the OK or Cancel buttons). Additionally, it should have a close function (emulating an OK button click on the modal) and a dismiss function (emulating a Cancel button click on the modal). Both the close and dismiss functions trigger the respective callback functions when invoked.

The unit test for displaying the modal with the ID 'modalId' returned an undefined value

Answer №1

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