How to test that one function is called before another - javascript

I have some tightly coupled legacy code that I want to cover with tests. Sometimes it's important to ensure that one mocked out method is called before another. A simplified example:
function PageManager(page) {
this.page = page;
}
PageManager.prototype.openSettings = function(){
this.page.open();
this.page.setTitle("Settings");
};
In the test I can check that both open() and setTitle() are called:
describe("PageManager.openSettings()", function() {
beforeEach(function() {
this.page = jasmine.createSpyObj("MockPage", ["open", "setTitle"]);
this.manager = new PageManager(this.page);
this.manager.openSettings();
});
it("opens page", function() {
expect(this.page.open).toHaveBeenCalledWith();
});
it("sets page title to 'Settings'", function() {
expect(this.page.setTitle).toHaveBeenCalledWith("Settings");
});
});
But setTitle() will only work after first calling open(). I'd like to check that first page.open() is called, followed by setTitle(). I'd like to write something like this:
it("opens page before setting title", function() {
expect(this.page.open).toHaveBeenCalledBefore(this.page.setTitle);
});
But Jasmine doesn't seem to have such functionality built in.
I can hack up something like this:
beforeEach(function() {
this.page = jasmine.createSpyObj("MockPage", ["open", "setTitle"]);
this.manager = new PageManager(this.page);
// track the order of methods called
this.calls = [];
this.page.open.and.callFake(function() {
this.calls.push("open");
}.bind(this));
this.page.setTitle.and.callFake(function() {
this.calls.push("setTitle");
}.bind(this));
this.manager.openSettings();
});
it("opens page before setting title", function() {
expect(this.calls).toEqual(["open", "setTitle"]);
});
This works, but I'm wondering whether there is some simpler way to achieve this. Or some nice way to generalize this so I wouldn't need to duplicate this code in other tests.
PS. Of course the right way is to refactor the code to eliminate this kind of temporal coupling. It might not always be possible though, e.g. when interfacing with third party libraries. Anyway... I'd like to first cover the existing code with tests, modifying it as little as possible, before delving into further refactorings.

I'd like to write something like this:
it("opens page before setting title", function() {
expect(this.page.open).toHaveBeenCalledBefore(this.page.setTitle);
});
But Jasmine doesn't seem to have such functionality built in.
Looks like the Jasmine folks saw this post, because this functionality exists. I'm not sure how long it's been around -- all of their API docs back to 2.6 mention it, though none of their archived older style docs mention it.
toHaveBeenCalledBefore(expected)
expect the actual value (a Spy) to have been called before another Spy.
Parameters:
Name Type Description
expected Spy Spy that should have been called after the actual Spy.
A failure for your example looks like Expected spy open to have been called before spy setTitle.

Try this:
it("setTitle is invoked after open", function() {
var orderCop = jasmine.createSpy('orderCop');
this.page.open = jasmine.createSpy('openSpy').and.callFake(function() {
orderCop('fisrtInvoke');
});
this.page.setTitle = jasmine.createSpy('setTitleSpy').and.callFake(function() {
orderCop('secondInvoke');
});
this.manager.openSettings();
expect(orderCop.calls.count()).toBe(2);
expect(orderCop.calls.first().args[0]).toBe('firstInvoke');
expect(orderCop.calls.mostRecent().args[0]).toBe('secondInvoke');
}
EDIT: I just realized my original answer is effectively the same as the hack you mentioned in the question but with more overhead in setting up a spy. It's probably simpler doing it with your "hack" way:
it("setTitle is invoked after open", function() {
var orderCop = []
this.page.open = jasmine.createSpy('openSpy').and.callFake(function() {
orderCop.push('fisrtInvoke');
});
this.page.setTitle = jasmine.createSpy('setTitleSpy').and.callFake(function() {
orderCop.push('secondInvoke');
});
this.manager.openSettings();
expect(orderCop.length).toBe(2);
expect(orderCop[0]).toBe('firstInvoke');
expect(orderCop[1]).toBe('secondInvoke');
}

Create a fake function for the second call that expects the first call to have been made
it("opens page before setting title", function() {
// When page.setTitle is called, ensure that page.open has already been called
this.page.setTitle.and.callFake(function() {
expect(this.page.open).toHaveBeenCalled();
})
this.manager.openSettings();
});

Inspect the specific calls by using the .calls.first() and .calls.mostRecent() methods on the spy.

Basically did the same thing. I felt confident doing this because I mocked out the function behaviors with fully synchronous implementations.
it 'should invoke an options pre-mixing hook before a mixin pre-mixing hook', ->
call_sequence = []
mix_opts = {premixing_hook: -> call_sequence.push 1}
#mixin.premixing_hook = -> call_sequence.push 2
spyOn(mix_opts, 'premixing_hook').and.callThrough()
spyOn(#mixin, 'premixing_hook').and.callThrough()
class Example
Example.mixinto_proto #mixin, mix_opts, ['arg1', 'arg2']
expect(mix_opts.premixing_hook).toHaveBeenCalledWith(['arg1', 'arg2'])
expect(#mixin.premixing_hook).toHaveBeenCalledWith(['arg1', 'arg2'])
expect(call_sequence).toEqual [1, 2]

Lately I've developed a replacement for Jasmine spies, called strict-spies, which solves this problem among many others:
describe("PageManager.openSettings()", function() {
beforeEach(function() {
this.spies = new StrictSpies();
this.page = this.spies.createObj("MockPage", ["open", "setTitle"]);
this.manager = new PageManager(this.page);
this.manager.openSettings();
});
it("opens page and sets title to 'Settings'", function() {
expect(this.spies).toHaveCalls([
["open"],
["setTitle", "Settings"],
]);
});
});

Related

Knockout pureComputed Not Working

I'm having a ridiculous time trying to handle addresses using Knockout. My structure is something like:
viewModel.buildings()[0].Address()...
Where Address is:
var Address = function () {
var self = this;
self.cAddr1 = ko.observable("");
self.cCity = ko.observable("");
...
self.cDisplay = ko.pureComputed(function () {
return self.cAddr1() + '<br>' + self.cCity() + ...;
}
self.AddressActions = new AddressActions();
}
Everything seems to work ok. Each building has an address and the observables are updated properly. The cDisplay also works correctly.
I am wanting to add another computed/observable/whatever that will call a function that is part of AddressActions when the address changes. I tried this, but the console.log never even gets hit which doesn't make any sense to me:
var Address = function () {
// Same as above...
...
self.triggerAddressVerify = ko.pureComputed(function () {
console.log('here');
self.cAddr1(); self.cAddr2(); self.cCity(); self.cState(); self.cZip();
self.AddressActions.VerifyAddress(self);
}
}
Any ideas why this isn't working?
Result
So I'm still new to knockout.js (obviously) but it works a little bit differently than I thought. I basically used the accepted answer but wrapped everything into a pureComputed. Here's what I ended up adding:
var Address = function () {
...
self.addressChangeEvent = ko.pureComputed(function () {
return self.cAddr1() + self.cAddr2() + self.cCity() self.cState() + self.cZip();
}
self.addressChangeEvent.subscribe(function () {
self.AddressActions.VerifyAddress(self);
}
}
it looks like you're looking for subscribe rather than computed
self.cAddr1.subscribe(function(){
self.AddressActions.VerifyAddress(self);
});
you can add a subscription for each variable you need an event for
The Knockout documentation for pure computed specifically says to not use it when you intend to perform some action (side effects).
You should not use the pure feature for a computed observable that is meant to perform an action when its dependencies change.
You can use a regular computed instead.
self.triggerAddressVerify = ko.computed(function () {
console.log('here');
self.cAddr1(); self.cAddr2(); self.cCity(); self.cState(); self.cZip();
self.AddressActions.VerifyAddress(self);
});
But note that this will run once initially as well as on future changes. If you only want to perform an action on future changes, your approach of subscribing to a pure computed is better.

How to spyon jquery selector [duplicate]

When it comes to spying on jQuery functions (e.g. bind, click, etc) it is easy:
spyOn($.fn, "bind");
The problem is when you want to spy on $('...') and return defined array of elements.
Things tried after reading other related answers on SO:
spyOn($.fn, "init").andReturn(elements); // works, but breaks stuff that uses jQuery selectors in afterEach(), etc
spyOn($.fn, "merge").andReturn(elements); // merge function doesn't seem to exist in jQuery 1.9.1
spyOn($.fn, "val").andReturn(elements); // function never gets called
So how do I do this? Or if the only way is to spy on init function how do I "remove" spy from function when I'm done so afterEach() routing doesn't break.
jQuery version is 1.9.1.
WORKAROUND:
The only way I could make it work so far (ugly):
realDollar = $;
try {
$ = jasmine.createSpy("dollar").andReturn(elements);
// test code and asserts go here
} finally {
$ = realDollar;
}
Normally, a spy exists for the lifetime of the spec. However, there's nothing special about destroying a spy. You just restore the original function reference and that's that.
Here's a handy little helper function (with a test case) that will clean up your workaround and make it more usable. Call the unspy method in your afterEach to restore the original reference.
function spyOn(obj, methodName) {
var original = obj[methodName];
var spy = jasmine.getEnv().spyOn(obj, methodName);
spy.unspy = function () {
if (original) {
obj[methodName] = original;
original = null;
}
};
return spy;
}
describe("unspy", function () {
it("removes the spy", function () {
var mockDiv = document.createElement("div");
var mockResult = $(mockDiv);
spyOn(window, "$").and.returnValue(mockResult);
expect($(document.body).get(0)).toBe(mockDiv);
$.unspy();
expect(jasmine.isSpy($)).toEqual(false);
expect($(document.body).get(0)).toBe(document.body);
});
});
As an alternative to the above (and for anyone else reading this), you could change the way you're approaching the problem. Instead of spying on the $ function, try extracting the original call to $ to its own method and spying on that instead.
// Original
myObj.doStuff = function () {
$("#someElement").css("color", "red");
};
// Becomes...
myObj.doStuff = function () {
this.getElements().css("color", "red");
};
myObj.getElements = function () {
return $("#someElement");
};
// Test case
it("does stuff", function () {
spyOn(myObj, "getElements").and.returnValue($(/* mock elements */));
// ...
});
By spying on the window itself you have access to any window properties.
As Jquery is one of these you can easily mock it as below and return the value you require.
spyOn(window, '$').and.returnValue(mockElement);
Or add a callFake with the input if it needs to be dynamic.

Custom browser actions in Protractor

The problem:
In one of our tests we have a "long click"/"click and hold" functionality that we solve by using:
browser.actions().mouseDown(element).perform();
browser.sleep(5000);
browser.actions().mouseUp(element).perform();
Which we would like to ideally solve in one line by having sleep() a part of the action chain:
browser.actions().mouseDown(element).sleep(5000).mouseUp(element).perform();
Clearly, this would not work since there is no "sleep" action.
Another practical example could be the "human-like typing". For instance:
browser.actions().mouseMove(element).click()
.sendKeys("t").sleep(50) // we should randomize the delays, strictly speaking
.sendKeys("e").sleep(10)
.sendKeys("s").sleep(20)
.sendKeys("t")
.perform();
Note that these are just examples, the question is meant to be generic.
The Question:
Is it possible to extend browser.actions() action sequences and introduce custom actions?
Yes, you can extend the actions framework. But, strictly speaking, getting something like:
browser.actions().mouseDown(element).sleep(5000).mouseUp(element).perform();
means messing with Selenium's guts. So, YMMV.
Note that the Protractor documentation refers to webdriver.WebDriver.prototype.actions when explaining actions, which I take to mean that it does not modify or add to what Selenium provides.
The class of object returned by webdriver.WebDriver.prototype.actions is webdriver.ActionSequence. The method that actually causes the sequence to do anything is webdriver.ActionSequence.prototype.perform. In the default implementation, this function takes the commands that were recorded when you called .sendKeys() or .mouseDown() and has the driver to which the ActionSequence is associated schedule them in order. So adding a .sleep method CANNOT be done this way:
webdriver.ActionSequence.prototype.sleep = function (delay) {
var driver = this.driver_;
driver.sleep(delay);
return this;
};
Otherwise, the sleep would happen out of order. What you have to do is record the effect you want so that it is executed later.
Now, the other thing to consider is that the default .perform() only expects to execute webdriver.Command, which are commands to be sent to the browser. Sleeping is not one such command. So .perform() has to be modified to handle what we are going to record with .sleep(). In the code below I've opted to have .sleep() record a function and modified .perform() to handle functions in addition to webdriver.Command.
Here is what the whole thing looks like, once put together. I've first given an example using stock Selenium and then added the patches and an example using the modified code.
var webdriver = require('selenium-webdriver');
var By = webdriver.By;
var until = webdriver.until;
var chrome = require('selenium-webdriver/chrome');
// Do it using what Selenium inherently provides.
var browser = new chrome.Driver();
browser.get("http://www.google.com");
browser.findElement(By.name("q")).click();
browser.actions().sendKeys("foo").perform();
browser.sleep(2000);
browser.actions().sendKeys("bar").perform();
browser.sleep(2000);
// Do it with an extended ActionSequence.
webdriver.ActionSequence.prototype.sleep = function (delay) {
var driver = this.driver_;
// This just records the action in an array. this.schedule_ is part of
// the "stock" code.
this.schedule_("sleep", function () { driver.sleep(delay); });
return this;
};
webdriver.ActionSequence.prototype.perform = function () {
var actions = this.actions_.slice();
var driver = this.driver_;
return driver.controlFlow().execute(function() {
actions.forEach(function(action) {
var command = action.command;
// This is a new test to distinguish functions, which
// require handling one way and the usual commands which
// require a different handling.
if (typeof command === "function")
// This puts the command in its proper place within
// the control flow that was created above
// (driver.controlFlow()).
driver.flow_.execute(command);
else
driver.schedule(command, action.description);
});
}, 'ActionSequence.perform');
};
browser.get("http://www.google.com");
browser.findElement(By.name("q")).click();
browser.actions().sendKeys("foo")
.sleep(2000)
.sendKeys("bar")
.sleep(2000)
.perform();
browser.quit();
In my implementation of .perform() I've replaced the goog... functions that Selenium's code uses with stock JavaScript.
Here is what I did (based on the perfect #Louis's answer).
Put the following into onPrepare() in the protractor config:
// extending action sequences
protractor.ActionSequence.prototype.sleep = function (delay) {
var driver = this.driver_;
this.schedule_("sleep", function () { driver.sleep(delay); });
return this;
};
protractor.ActionSequence.prototype.perform = function () {
var actions = this.actions_.slice();
var driver = this.driver_;
return driver.controlFlow().execute(function() {
actions.forEach(function(action) {
var command = action.command;
if (typeof command === "function")
driver.flow_.execute(command);
else
driver.schedule(command, action.description);
});
}, 'ActionSequence.perform');
};
protractor.ActionSequence.prototype.clickAndHold = function (elm) {
return this.mouseDown(elm).sleep(3000).mouseUp(elm);
};
Now you'll have sleep() and clickAndHold() browser actions available. Example usage:
browser.actions().clickAndHold(element).perform();
I think it is possible to extend the browser.actions() function but that is currently above my skill level so I'll lay out the route that I would take to solve this issue. I would recommend setting up a "HelperFunctions.js" Page Object that will contain all of these Global Helper Functions. In that file you can list your browser functions and reference it in multiple tests with all of the code in one location.
This is the code for the "HelperFunctions.js" file that I would recommend setting up:
var HelperFunctions = function() {
this.longClick = function(targetElement) {
browser.actions().mouseDown(targetElement).perform();
browser.sleep(5000);
browser.actions().mouseUp(targetElement).perform();
};
};
module.exports = new HelperFunctions();
Then in your Test you can reference the Helper file like this:
var HelperFunctions = require('../File_Path_To/HelperFunctions.js');
describe('Example Test', function() {
beforeEach(function() {
this.helperFunctions = HelperFunctions;
browser.get('http://www.example.com/');
});
it('Should test something.', function() {
var Element = element(by.className('targetedClassName'));
this.helperFunctions.longClick(Element);
});
});
In my Test Suite I have a few Helper files setup and they are referenced through out all of my Tests.
I have very little knowledge of selenium or protractor, but I'll give it a shot.
This assumes that
browser.actions().mouseDown(element).mouseUp(element).perform();
is valid syntax for your issue, if so then this would likely do the trick
browser.action().sleep = function(){
browser.sleep.apply(this, arguments);
return browser.action()
}

How to pass parameter from spec to reporter in Jasmine?

I am writing a jasmine reporter, and I want to be able to pass parameters from individual specs to the reporter. For example:
the spec:
// I prefer this way
it("my spec 1", function() { ... }, { myParam: true });
// But this way would also be fine if it can work
it("my spec 2", function() {
this.myParam = true;
...
});
the reporter:
this.specDone = function(specResult) {
var myParam = // some way to access myParam
...
}
I haven't found any documentation for something like this, nor any example of something similar in other reporters.
I also tried debugging the flow of jasmine to see what objects get passed to each method but so far I had no luck in finding a simple solution.
How can this be done?
I found one possible solution - in boot.js
var jasmineInterface = {
it: function(desc, func, properties) {
var spec = env.it(desc, func);
spec.result.myParam = (properties || {}).myParam;
return spec;
},
...
and then in the reporter:
this.specDone = function(specResult) {
var myParam = specResult.myParam;
...
}
of course you can (and should) make this more generic to fit other cases.

YUI.Test assertion doesn't fail when it is in event's callback

I'm using version 3.4.0
I have a strange problem with YUI.Test assertion. Here is the example:
YUI().use('test', 'node', 'node-event-simulate',
function(Y) {
var runner = Y.Test.Runner;
var someTestCase = new Y.Test.Case({
name : 'SomeMeaningfulName',
setUp : function() {
var test = this;
// create show details link
test.Y$aLink = Y.Node
.create('Show details');
Y.one('body')
.append(test.Y$aLink);
},
tearDown : function() {
this.Y$aLink.remove();
},
testEventListener : function() {
var test = this;
test.Y$aLink
.on('click', function(e) {
e.preventDefault();
// this codes works
console.log('on click event');
// this one doesn't fail
// it "works" perfectly when it's outside of the callback
Y.assert(false, 'false is true');
});
test.Y$aLink.simulate('click');
}
});
runner.add(someTestCase);
runner.run();
});
The assertion never fails when it's inside of the event's callback :(
Documentation doesn't mention this situation...
Maybe I'm doing something wrong, but there is a lack of documentation makes it hard to be sure...
UPDATE
example without wait/resume:
http://jsfiddle.net/op1ekun/Fgra6/2/
and the one with wait/resume
http://jsfiddle.net/op1ekun/Fgra6/5/
UPDATE2
there is a similar case already reported, it touches asynchronous testing issue, but it's not my problem exactly:
http://yuilibrary.com/projects/yuitest/ticket/74
UPDATE3
this seems to be exactly what I'm experiencing and looks a solution already proposed by Billy, the interesting thing is to use dependency injection, it might be worth a try:
http://csausdev.wordpress.com/2011/02/12/unit-testing-callbacks-with-yui-test/
Please help!
Thanks!
YUI Test has a wait and resume mechanism you can leverage in this case. You tell it to wait until a resume method is called, and the resume method takes a callback where you can safely make assertions. In your case it would look like this:
'test event listener': function () {
var test = this;
test.Y$aLink.on('click', function (e) {
e.preventDefault();
test.resume(function () {
Assert.fail('ouch!');
});
});
test.wait();
test.Y$aLink.simulate('click');
}

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