问题描述
您好我有一个使用AngularJS（1.5.11）编写的功能完整的网络应用程序，现在我开始使用业力（0.12.37），grunt-karma（0.8.3），karma-chrome进行单元测试-launcher（0.1.12），karma-phantomjs-launcher（1.0.4）， phantomjs-prebuilt （2.1.14），jasmine-promise-matchers（2.3.0）和karma-jasmine（ 0.1.6），1.3.x Jasmine版本。
Hi I have a feature complete web-app written using AngularJS (1.5.11) and now I'm getting started with unit testing using karma (0.12.37), grunt-karma (0.8.3), karma-chrome-launcher (0.1.12), karma-phantomjs-launcher (1.0.4), phantomjs-prebuilt (2.1.14), jasmine-promise-matchers (2.3.0) and karma-jasmine (0.1.6), with a 1.3.x Jasmine version.
我对测试异步内容不是很有信心，所以我开始在Google上搜索，我总是看到在调用异步函数之后，运行AngularJS异步测试的唯一必要条件是 $ rootScope / $ scope。$ apply / $ digest 。
I'm not very confident in testing asynchronous stuff, so I started googling around and I always end up seeing the only mandatory thing to run AngularJS async tests is a $rootScope/$scope.$apply/$digest right after the async function has been called.
最终我发现并在此特别顺畅，但在使用phantomjs-launcher时失败，抛出如下错误：
Eventually I found someone suggesting me to use runs() and waitsFor() and the test in this plunkr in particular runs smoothly when using the chrome-launcher but fails when using phantomjs-launcher, throwing an error like the following:
Expected { myError : { error : 'error_message' }, line : <factory's line of code which throws the error>, sourceURL : 'path/to/factory.js', stack :
<function throwing error> B@path/to/factory.js:<factory's line of code which throws the error>
<"async" function> A@path/to/factory.js:<factory's line of code which calls B()>
path/to/factory-spec.js:<the following line of code: var promise = HandleService.A();>
invoke@path/to/angular/angular.js:4771:24
WorkFn@path/to/angular-mocks/angular-mocks.js:3130:26
execute@path/to/node_modules/karma-jasmine/lib/jasmine.js:1145:22
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2177:38
start@path/to/node_modules/karma-jasmine/lib/jasmine.js:2130:13
execute@path/to/node_modules/karma-jasmine/lib/jasmine.js:2458:19
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2177:38
start@path/to/node_modules/karma-jasmine/lib/jasmine.js:2130:13
execute@path/to/node_modules/karma-jasmine/lib/jasmine.js:2604:19
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2177:38
start@path/to/node_modules/karma-jasmine/lib/jasmine.js:2130:13
execute@path/to/node_modules/karma-jasmine/lib/jasmine.js:2604:19
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2177:38
onComplete@path/to/node_modules/karma-jasmine/lib/jasmine.js:2173:23
finish@path/to/node_modules/karma-jasmine/lib/jasmine.js:2561:15
path/to/node_modules/karma-jasmine/lib/jasmine.js:2605:16
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2187:24
onComplete@path/to/node_modules/karma-jasmine/lib/jasmine.js:2173:23
finish@path/to/node_modules/karma-jasmine/lib/jasmine.js:2561:15
path/to/node_modules/karma-jasmine/lib/jasmine.js:2605:16
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2187:24
onComplete@path/to/node_modules/karma-jasmine/lib/jasmine.js:2173:23
finish@path/to/node_modules/karma-jasmine/lib/jasmine.js:2432:15
path/to/node_modules/karma-jasmine/lib/jasmine.js:2459:16
next_@path/to/node_modules/karma-jasmine/lib/jasmine.js:2187:24
path/to/node_modules/karma-jasmine/lib/jasmine.js:2167:23' }, pending : undefined, processScheduled : false } } to be rejected with { myError : { error : 'error_message' } }.
所以我开始认为Chrome结果是误报，我需要重写异步测试：因此我试过这样的，但现在PhantomJs和Chrome中的测试都失败了与预期的超时消息：
So I started to think Chrome results were false positive, and I needed to rewrite the async tests: hence I tried with something like this plunkr, but now the tests fail both in PhantomJs and Chrome with the expected timeout message:
timeout: timed out after 1500 msec waiting for A should catch an error
NB： 我无法将Jasmine更新为2.0版并使用完成参数机制现在如果我做对了，我甚至不应该手动触发 $ rootScope。$ apply / $ digest 使用时。
N.B.: I can't update Jasmine to version 2.0 and use the done parameter mechanism now and if I got it right I should not even manually trigger a $rootScope.$apply/$digest when using jasmine-promise-matchers.
推荐答案
Angular'async'测试通常是同步的，因此 waitsFor 和运行是不必要的，显然有害。
Angular 'async' tests are generally synchronous, thus waitsFor and runs are unnecessary and apparently harmful.
确实， jasmine-promise-matchers 不需要手动触发摘要来执行$ q promises，因为这是在内部完成的。
Indeed, jasmine-promise-matchers don't need to trigger a digest manually to execute $q promises since this is done internally.
这里的问题是竞争条件。第一个运行似乎在 $ rootScope。$ digest（）之后运行，而 catch 块永远不会被执行 - 所以是第二个运行。
The problem here is race condition. First runs seems to run after $rootScope.$digest(), and catch block is never executed - so is second runs.
相反，它应该同步测试：
Instead, it should be tested synchronously:
it('it actually throws an error, yay', function () {
var promise = HandleService.A();
expect(promise).toBePromise();
expect(promise).toBeRejectedWith(jasmine.objectContaining({
myError: {error: 'error_message'}
}));
});
这篇关于为什么我在Jasmine 1.3.x中的AngularJS异步测试不起作用？的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持！