单元测试Angular中$ sce.trustAsHtml的输出

Question

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,因此我可以在视图中显示它们.

起初,博客帖子只是显示为文本<p>Blog body</p>,而不是渲染为解析的HTML,直到我发现你可以将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.

单元测试时会出现问题.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:

调节器

.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;
    });
})

单元测试

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);
    });
});

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 } }     ].

我怀疑问题是由于$sce.trustAsHtml返回包含函数的对象而不是字符串的事实.

我的问题是,首先,我是否以正确的方式处理这个问题？

其次,如果是这样,我该如何测试输出$sce.trustAsHtml？

Answer 1

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,它将每个字符串的出现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>'));
    };
});

我使用$ sce服务将结果值信任为HTML.为了测试这个,我需要对结果值使用$$ 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>.'); 
}));

更新:

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>.');
}));

Answer 2

在每次测试之前,您必须使用其提供程序禁用$ sce.

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>');
}));

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
});

Answer 3

我发现你可以使用$sce.getTrusted哪个将返回最初传递给的值$sce.trustAsHtml,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.

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>');
});