单元测试Angular中$ sce.trustAsHtml的输出

I am writing a REST app in Angular and I want to write unit tests for it (of course!). I have a controller which gets a list of blog posts from a REST service in json and puts the summaries into the $scope, so I can display them in the view.

我正在Angular中编写一个REST应用程序，我想为它编写单元测试（当然！）。我有一个控制器，它从json中的REST服务获取博客文章列表，并将摘要放入$ scope，所以我可以在视图中显示它们。

At first the blog posts were just displaying as text ie <p>Blog body</p>, rather than rendering as parsed HTML, until I discovered that you can use ng-bind-html in conjunction with the $sce service. This now works fine in terms of displaying the blog posts correctly.

起初，博客文章只是显示为文本，即

博客主体 ，而不是呈现为已解析的HTML，直到我发现您可以将ng-bind-html与$ sce服务结合使用。这在正确显示博客文章方面现在可以正常工作。

The problem arises when unit testing. I am trying to mock a json response with some HTML and then test that my controller is correctly dealing with the HTML. Here is my code:

单元测试时出现问题。我试图用一些HTML模拟一个json响应，然后测试我的控制器是否正确处理HTML。这是我的代码：

Controller

.controller( 'HomeCtrl', function HomeController( $scope, $http, $sce ) {
    $scope.posts = {};
    $http.get('../drupal/node.json').success(function (data) {
        var posts;
        posts = data.list;

        for(var i = 0; i < posts.length; i ++) {
            posts[i].previewText = $sce.trustAsHtml(posts[i].body.summary);
            posts[i].created = posts[i].created + '000'; // add milliseconds so it can be properly formatted 
        }
        $scope.posts = posts;
    });
})

unit test

describe('HomeCtrl', function() {
    var $httpBackend, $rootScope, $sce, createController;

    beforeEach(inject(function ($injector) {
        // Set up the mock http service responses
        $httpBackend = $injector.get('$httpBackend');

        // Get hold of a scope (i.e. the root scope)
        $rootScope = $injector.get('$rootScope');
        // The $controller service is used to create instances of controllers
        var $controller = $injector.get('$controller');

        $sce = $injector.get('$sce');

        createController = function() {
            return $controller('HomeCtrl', {
                '$scope': $rootScope
            });
        };
    }));

    it('should get a list of blog posts', function() {
        var rawResponse = {
            "list": [
                {
                    "body": {
                        "value": "\u003Cp\u003EPost body.\u003C\/p\u003E\n",
                        "summary": "\u003Cp\u003ESummary.\u003C\/p\u003E\n"
                    },
                    "created": "1388415860"
                }
            ]};
        var processedResponse = [{
                "body": {
                    "value": "\u003Cp\u003EPost body.\u003C\/p\u003E\n",
                    "summary": "\u003Cp\u003ESummary.\u003C\/p\u003E\n"
                },
                "created": "1388415860000",
            previewText: $sce.trustAsHtml("\u003Cp\u003ESummary.\u003C\/p\u003E\n")
        }];

        $httpBackend.when('GET', '../drupal/node.json').respond(rawResponse);
        $httpBackend.expectGET("../drupal/node.json").respond(rawResponse);
        var homeCtrl = createController();
        expect(homeCtrl).toBeTruthy();
        $httpBackend.flush();
        expect($rootScope.posts).toEqual(processedResponse);
    });
});

When I run the above through the Karma test runner, I get the following response:

当我通过Karma测试运行器运行上述内容时，我收到以下响应：

Chrome 31.0.1650 (Windows) home section HomeCtrl should get a list of blog posts FAILED
    Expected [ { body : { value : '<p>Post body.</p>
    ', summary : '<p>Summary.</p>
    ' }, created : '1388415860000', previewText : { $$unwrapTrustedValue : Function } }          ] to equal [ { body
: { value : '<p>Post body.</p>
    ', summary : '<p>Summary.</p>
    ' }, created : '1388415860000', previewText : { $$unwrapTrustedValue : Function } }     ].

I suspect the problem is due to the fact that $sce.trustAsHtml returns an object containing a function, rather than a string.

我怀疑问题是由于$ sce.trustAsHtml返回一个包含函数的对象，而不是字符串。

My question is, firstly, am I approaching this problem in the correct way?

我的问题是，首先，我是否以正确的方式处理这个问题？

Secondly, if so, how should I go about testing the output of $sce.trustAsHtml?

其次，如果是这样，我应该如何测试$ sce.trustAsHtml的输出？

4 个解决方案

#1

Since the answer given by michael-bromley didn't work for me I want to point out another solution. In my case I was using a filter that wraps each occurrence of a string in another string with a span that has a class of 'highlight'. In other words, I want words to be highlighted. Here is the code:

由于michael-bromley给出的答案对我不起作用，我想指出另一种解决方案。在我的情况下，我使用的是一个过滤器，它将每次出现的字符串包装在另一个字符串中，其字符串的类别为“highlight”。换句话说，我希望突出显示单词。这是代码：

angular.module('myModule').filter('highlight', function ($sce) {
    return function (input, str) {
        return $sce.trustAsHtml((input || '').replace(new RegExp(str, 'gi'), '<span class=\"highlighted\">$&</span>'));
    };
});

I use the $sce service to trust the resulting value as HTML. To test this I need to use the $$unwrapTrustedValue function on the resulting value to get my test working:

我使用$ sce服务将结果值信任为HTML。为了测试这个，我需要在结果值上使用$$ unwrapTrustedValue函数来使我的测试工作：

it('01: should add a span with class \'highlight\' around each mathing string.', inject(function ($filter) {
    // Execute
    var result = $filter('highlight')('this str contains a str that will be a highlighted str.', 'str');

    // Test
    expect(result.$$unwrapTrustedValue()).toEqual('this <span class="highlighted">str</span> contains a <span class="highlighted">str</span> that will be a highlighted <span class="highlighted">str</span>.'); 
}));

UPDATE:

更新：

As @gugol kindly pointed out it is preferred not to use Angular internal methods like $$unwrapTrustedValue. A better approach is to use the public getTrustedHtml method on the $sce service. Like so:

正如@gugol所指出的那样，最好不要使用像$$ unwrapTrustedValue这样的Angular内部方法。更好的方法是在$ sce服务上使用public getTrustedHtml方法。像这样：

it('01: should add a span with class \'highlight\' around each mathing string.', inject(function ($sce, $filter) {
    // Execute
    var result = $filter('highlight')('this str contains a str that will be a highlighted str.', 'str');

    // Test
    expect($sce.getTrustedHtml(result)).toEqual('this <span class="highlighted">str</span> contains a <span class="highlighted">str</span> that will be a highlighted <span class="highlighted">str</span>.');
}));

#2

You have to disable $sce using its provider before each test.

您必须在每次测试之前使用其提供程序禁用$ sce。

When $sce is disabled all $sce.trust* methods just return original value instead of a wrapper function.

当$ sce被禁用时，所有$ sce.trust *方法只返回原始值而不是包装函数。

beforeEach(module(function ($sceProvider) {
  $sceProvider.enabled(false);
}));

it('shall pass', inject(function($sce){
  expect($sce.trustAsHtml('<span>text</span>')).toBe('<span>text</span>');
}));

In your particular example just do this:

在您的特定示例中，只需这样做：

describe('HomeCtrl', function() {
  var $httpBackend, $rootScope, $sce, createController;

  beforeEach(module(function ($sceProvider) {
    $sceProvider.enabled(false);
  }));

  // rest of the file
});

#3

I discovered that you can use $sce.getTrusted which will return the value originally passed to $sce.trustAsHtml, in this case a string containing HTML, which you can then test for equality in the usual way.

我发现你可以使用$ sce.getTrusted，它将返回最初传递给$ sce.trustAsHtml的值，在这种情况下是一个包​​含HTML的字符串，然后你可以用通常的方式测试它是否相等。

So my test now looks like this:

所以我的测试现在看起来像这样：

it('should create a previewText property using $sce.trustAsHtml', function() {
    // confirms that it is an object, as should be the case when 
    // it has been through $sce.trustAsHtml
    expect(typeof result.previewText === 'object').toEqual(true);

    expect($sce.getTrusted($sce.HTML, result.previewText))
      .toEqual('<p>Original HTML content string</p>');
});

#4

Another option is to use the getTrustedHtml() function to get the html string value from $$unwrapTrustedValue.

另一种选择是使用getTrustedHtml（）函数从$$ unwrapTrustedValue获取html字符串值。

vm.user.bio = $sce.getTrustedHtml(vm.user.bio);