angularjs - Testing services w/ $httpBackend in AngularJS

Question

I have a service with about a dozen methods hanging off it. I'm setting up my first round of unit tests. Here's a simple example that's working:

it('should have a working getter/setter for SummaryLayoutBn', function() {
    layoutService.setCurrentSummaryLayoutBn('TEST_BN');
    summaryLayoutBn = layoutService.getCurrentSummaryLayoutBn();
    expect(summaryLayoutBn).toEqual('TEST_BN');
}); 

I'm then using $httpBackend to return some mocked json data:

it('should have a working getLayout function', function() {

    $httpBackend.expectGET('/b/json/layout/TEST_BN').respond(defaultSystemLayout);

    expect(layoutCtrlScope.layoutModel.layout).toBeUndefined();

    layoutCtrlScope.loadLayoutFromBn('TEST_BN');

    $httpBackend.flush();

    expect(layoutCtrlScope.layoutModel.layout).toBe(defaultSystemLayout)
});

This is working, but I'm no longer calling my service, I'm calling a function in my controller that calls the service. Is this the right way to do this? It allows me to test that the layoutCtrlScope.layoutModel.layout, but that feels like a test for the controller.

Here is the layout service

getLayout: function (bn) {
    utilService.showLoading();
    var url = baseUrl.generateUrl(baseUrl.layout, bn);
    return $http.get(url).
        success(function (data, status, headers, config) {
            utilService.hideLoading();
        }).
        error(function (data, status, headers, config) {
            errorHandlingService.handleGenericError(status);
        utilService.hideLoading();
        });
}

And the controller function:

$scope.loadLayoutFromBn = function (layoutBn) {
      var layout = layoutService.getLayout(layoutBn);
      layout.then(function (data) {
          $scope.layoutModel.layout = data.data;
      });
}