javascript 茉莉花间谍 callThrough 和 callFake
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Jasmine spies callThrough and callFake
提问by kkudi
I have a scenario whereby I want to call done()on a beforeEachafter a callback has been invoked.
我有一种情况，其中我想打电话给done()在beforeEach回调已被调用后。
I tried to do this as follows :
我尝试这样做：
spyOn(scope, 'onAdmin').and.callThrough().and.callFake(function(){done()})
But I'm not sure I get the right behaviour. Essentially what I want to achieve is to be able to call done()after each callback is done doing what it does.
但我不确定我的行为是否正确。基本上我想要实现的是能够done()在每个回调完成后调用它所做的事情。
UPDATE: workaround solution
更新：变通解决方案
scope.onAdminBackup = scope.onAdmin;
spyOn(scope, 'onAdmin').and.callFake(function(admin) {
scope.onAdminBackup();
done() ;
})
回答by Sten Muchow
I have never chained these kinds of functions together cuz in my mind they seem to do the opposite. You are saying when I call this method -onAdmin - in the scope call it as normal. Which is what the callThrough method jasmine provides for us does.
我从来没有将这些类型的功能链接在一起，因为在我看来它们似乎正好相反。您是说当我调用此方法时 -onAdmin - 在范围内正常调用它。这就是 jasmine 为我们提供的 callThrough 方法所做的。
But then you are chaining along a callFake method as well so then you say but dont actually call it call this fake function instead - very conflicting.
但是然后你也沿着一个 callFake 方法链接，所以你说但实际上并没有调用它而是调用这个假函数 - 非常矛盾。
If you want to call spy on the method onAdmin and instead of it being fired you want it to do something else - something mocked - then use the .and.callFake(fn). Also take into account like @stefan above said - dont invoke the function - callFake is simply wanting a function as a parameter it will take care of calling it itself.
如果你想在 onAdmin 方法上调用 spy 而不是它被触发，你希望它做其他事情 - 一些嘲笑 - 然后使用 .and.callFake(fn)。还要考虑到像上面所说的@stefan - 不要调用函数 - callFake 只是想要一个函数作为参数，它会自己调用它。
This might be more along the lines of what you are looking for, if not show us some more code.
如果没有向我们展示更多代码，这可能更符合您的要求。
spyOn(scope, 'onAdmin')and.callFake(done)
回答by stefan
you are calling done right-away when you write done() try passing in done as a value:
您在编写 done() 时立即调用 done() 尝试将 done 作为值传递：
spyOn(scope, 'onAdmin').and.callThrough().and.callFake(done)
回答by Max Litvak
I found a work around way to do this. Jasmine has a method called addSpyStategy where you can add a custom strategy like callThrough or callFake. It would look something like this:
我找到了一种解决方法来做到这一点。Jasmine 有一个名为 addSpyStategy 的方法，您可以在其中添加自定义策略，例如 callThrough 或 callFake。它看起来像这样：
jasmine.addSpyStrategy('callThroughAndThen', (spy, fn) => {
return () => {
spy.and.callThrough();
setTimeout(() => fn(), 0);
}
});
the timeout makes sure the real function finishes before executing the custom function. Then for your spy, you can do this:
超时确保真正的函数在执行自定义函数之前完成。然后对于你的间谍，你可以这样做：
const spy = spyOn(scope, 'onAdmin')
spy.and.callThroughAndThen(spy, () => {
// your custom callback
done();
});
note: make sure to put custom strategy in a beforeEach block
注意：确保将自定义策略放在 beforeEach 块中
