Testing $resource services in AngularJS

You can mock the requests made by ngResource like this:

describe('User', function () {
    var mockUserResource, $httpBackend;
    beforeEach(angular.mock.module('myApp'));

    beforeEach(function () {
        angular.mock.inject(function ($injector) {
            $httpBackend = $injector.get('$httpBackend');
            mockUserResource = $injector.get('User');
        })
    });

    describe('getUser', function () {
        it('should call getUser with username', inject(function (User) {
            $httpBackend.expectGET('/api/index.php/users/test')
                .respond([{
                username: 'test'
            }]);

            var result = mockUserResource.getUser('test');

            $httpBackend.flush();

            expect(result[0].username).toEqual('test');
        }));

    });
});

Demo