Testing an Angular directive with isolate scope and parent controller - angularjs

Question

I have a directive which creates an isolate scope and has a parent directive controller through the require option. In the link function I am adding some methods to the scope.
When I am trying to compile the directive in my test, I can't seem to get access to the methods I added in the link function, even though the link function is definitely executing.
The scope I have just seems to be an empty child scope of $rootScope. I have tried using element.isolateScope() but this just seems to give me the scope of the parent directive.
I am probably compiling something wrong, can someone help?
parent-directive.js
angular.module("app").directive("sortHead", function() {
return {
restrict: "A",
controller: function ($scope) {
$scope.sortField = undefined;
$scope.reverse = false;
this.setSortField = function(value) {
$scope.sortField = value;
};
this.setReverse = function(value) {
$scope.reverse = value;
};
this.getSortField = function(value) {
return $scope.sortField;
};
this.getReverse = function(value) {
return $scope.reverse;
};
}
};
});
directive-to-test.js
angular.module("app").directive("sortHeader", function() {
return {
restrict: "A",
templateUrl: "templates/sortHeader.html",
scope: {
title: "#",
sort: "#"
},
require: "^sortHead",
link: function(scope, element, attrs, controller) {
scope.sortBy = function(name) {
if (controller.getSortField() === name) {
controller.setReverse(!controller.getReverse());
} else {
controller.setSortField(name);
controller.setReverse(false);
}
};
scope.getSortField = function() {
return controller.getSortField();
};
scope.getReverse = function() {
return controller.getReverse();
};
}
};
});
test.js
beforeEach(inject(function ($rootScope, $compile) {
scope = $rootScope.$new();
element = angular.element("<th sort-header title='Name' sort='name'></th>");
$compile(element)(scope);
scope.$digest();
}));

Answer 1

The test doesn't seem to be workable in its current form.
Here is a plunker with fixed spec
beforeEach(module('app'));
beforeEach(inject(function ($rootScope, $compile, $templateCache, sortHeaderDirective) {
scope = $rootScope.$new();
$templateCache.put(sortHeaderDirective[0].templateUrl, '');
element = angular.element("<th sort-header title='Name' sort='name'></th>");
element.data('$sortHeadController', {});
$compile(element)(scope);
scope.$digest();
}));
it("should do something", inject(function () {
expect(element.isolateScope().title).toEqual('Name');
}));