Xctest setup

A test case is a group of related test methods, with optional setup and teardown before and after tests are run. Measures the performance of a block of code, optionally deferring the why can t i verify my age on netflix point for measurement. To create asynchronous test expectations, use the convenience methods below, or create instances of XCTest Expectation and its subclasses manually as described in Asynchronous Tests and Expectations.

Creates an expectation that is fulfilled if the predicate returns true when evaluated with the given object. Creates an expectation that is fulfilled when a specific NSNotification is received for a given object. Creates an expectation that uses Key Value Observing to observe a value until it matches an expected value. Creates an expectation that uses Key Value Observing to observe a value and respond to changes in that value by calling a provided handler.

To wait for asynchronous test expectations to be fulfilled, use the convenience methods below, or create an instance of XCTWaiter. Waits on an array of expectations and specifies whether they must be fulfilled in the given order. A block to be called when a call to wait For Expectations timeout: handler: has all of its expectations fulfilled, or times out.

Use the symbols below if you need more customization for test case creation, such as to define test cases that cannot be known at compile time. Language: Swift Objective-C. Class XCTest Case. The primary class for defining test cases, test methods, and performance tests. SDK Xcode 7. Framework XCTest. Topics Customizing Test Setup and Teardown. Article Understanding Setup and Teardown for Test Methods Prepare initial state before tests run and perform cleanup after tests complete.

Handling Test Case Failure. Measuring Performance. Creating Asynchronous Test Expectations. Name, object : Any? Waiting for Expectations. Waits until all expectations are fulfilled or the timeout is reached. Monitoring UI Interruptions.

Creating Tests Programmatically. The invocation used when this test is run. Instance Properties. Type Properties. Instance Methods. Relationships Inherits From. Conforms To. CVar Arg. XCTWaiter Delegate. Article Defining Test Cases and Test Methods Add test cases and test methods to a test target to confirm that your code behaves as expected.A few days ago, I wrote about how to do dependency injection in Swift using the default XCTest framework.

Inspired by RSpecSpectaand Ginkgo. This process will become even easier once CocoaPods support for Swift is official. The app just shows a tableView of minion names and images. To get set up, I have a few basic objects set to go:. The Minion struct holds information about each Minion. To make it simple, each Minion has a unique name, so two Minions with the same name are actually the same Minion as specified by the Equatable protocol extension :.

Finally, this is the ViewController.

xctest setup

Notice that fetchMinions: takes in a minionService as an argument — this is so we can inject our own version of the minionService for testing purposes you can read more about this in my dependency injection post.

You should test everything of course your code is only as good as your tests! I want to test a few things:. Now comes the fun part! Create a new ViewControllerSpec. To use Quick, you have to import Quick and Nimble into your tests.

Also, your test class needs to be a subclass of QuickSpec :. In Quick, you can use beforeEach instead. I can make that clear by wrapping my tests in a describe block:. The fetchMinions: code has two scenarios — one when the API call via the minionService succeeds, and one where it fails. We can wrap these two scenarios into a context block:.

The outcome of each context should now be wrapped in an it block — there could be multiple it blocks if there are multiple side-effects you need to test. Finally, you can write the code to test your expectation. Quick is set up with multiple expectation matchers to assert expected outcomes — this is where the testing actually happens:.

I really enjoy writing tests with Quick — they are very human-readable. Sometimes when a test fails, the error message disappears right after appearing. Overall, I really like Quick, especially for using with Swift.

Creating our first unit test using XCTest

Have you tried using Quick? What has your experience been? You can view the sourcecode for this post on Github here. Enjoy the article?At the core of test-driven development lies the concept that you should begin by writing a test that succeeds only when your code works the way you want it to.

It might seem strange at first, but it makes a lot of sense: your new test will fail at first because your program doesn't do the right thing, then it's your job to write just enough code but no more! We're going to follow this approach here, but we need to do a little bit of setup work first so that we're able to write a failing test. Click Next, then name it PlayData. We'll be using this to store all the words in the plays. The goal right now is to write just enough code for us to return to testing, so for now just put this text into the file:.

That's it: there's a class called PlayDataand we've given it a property called allWords that will hold an array of strings. We're not going to fill that array with data yet, though: first we need to write a test to check that allWords has been populated with the words from the plays.

For now, just to make sure you understand how an XCTest works, we're going to write a test that checks allWords has exactly 0 strings inside it. Look in the "Project39Tests" for Project39Tests. You'll see it contains four methods: setUptearDownas well as two example test methods, all wrapped up in a class that inherits from XCTestCase. We're going to write a very basic test that checks allWords has 0 items inside.

Please add this method just below tearDown :. If we include the method name and the closing brace, that's only four lines of code, none of which look that difficult. However, it masks quite a lot of functionality, so I want to walk through exactly what it does and why. First, the method has a very specific name: it starts with "test" all in lowercase, it accepts no parameters and returns nothing. When you create a method like this inside an XCTestCase subclass, Xcode automatically considers it to be a test that should run on your code.

When Xcode recognizes a test, you'll see an empty gray diamond appear in the left-hand gutter, next to the line numbers. If you hover over that — but don't click it just yet! The first line of our testAllWordsLoaded method does nothing surprising: it just creates a new PlayData object so we have something to test with. This checks that its first parameter playData.

xctest setup

If it doesn't, the test will fail and print the message given in parameter three "allWords must be 0". Now that you understand how the test works, hover over the gray diamond next to the test and click its play button. Xcode will run this single test, which means launching the app in the iOS Simulator and verifying that the allWords array contains 0 items. Because we haven't written any loading code yet, this test will succeed and the diamond will turn into a green checkmark. You'll also see a green checkmark next to the class name at the top, which means that all tests in this class passed last time they were run.

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Sponsor Hacking with Swift and reach the world's largest Swift community! Articles Learn Start Here.Almost four months ago, our team Marco, Arne, and Daniel set out to write the model layer of a new app. We wanted to use testing as part of our development process. After some discussion, we chose XCTest as our testing framework. Our code base excluding tests has since grown to kilobytes of source code spread across files and 18, lines.

We wanted to share some of what we have learned, both about testing in general, and about testing with XCTest. Note that some of the model classes and methods in this article have been renamed, because the project is not in the App Store yet. With this article, we hope to shed some light on when XCTest is a good option, and when you might want to pick something else.

We tried to link to the other articles in this issue where it makes sense. But it is also important to remember that even when writing the first version of any code, most of the time will be spent changing code — as the project evolves, more and more features get added, and we realize that behavior needs to change slightly here and there. We are still finishing the initial version of our framework, and have just recently passed 1, test cases with more than 10 man months of effort spent on the project.

The ever-growing set of test cases have helped us do this. Apple has some decent documentation on using XCTest. Tests are grouped into classes that subclass from XCTestCase. Each method that has a name starting with test is a test. Because tests are simply classes and methods, we can add property and helper methods to the class, as we see fit. In order to be able to reuse code, we have a common superclass, TestCasefor all our test classes.

This class subclasses from XCTestCase. All our test classes subclass from our TestCase. We also put shared helper methods into the TestCase class.

And we even have properties on it that get pre-populated for each test. Since a test is simply a method that begins with the word testa typical test method would look like this:. But which class and method being tested should be obvious by simply looking at the test. There is a test case class for each production code class, and one is named after the other, e. If a class gets a bit bigger, we use categories to split up the test by topics.

We structure our tests by using the Given-When-Then pattern — every test is split into three parts. The given section sets up the environment for the test by creating model objects or bringing the system under test to a certain state. The when section contains the code we want to test. In most cases, this is only one method call. In the then section, we check the result of our action: Did we get the desired output?

Was the object changed? This section consists mainly of assertions. This simple pattern makes it easier to write and understand tests, as they all follow the same basic pattern.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. The dark mode beta is finally here.

Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I'm writing integration tests in Xcode 6 to go alongside my unit and functional tests. XCTest has a setUp method that gets called before every test. However, I would like to populate my test database with test data before every test and setUp just starts executing tests before the async database call is done.

Here's an example of what I have do now. Since setUp returns before the database is done populating I have to duplicate a lot of test code every test:.

XCTest Tutorial - The basics

There are two techniques for running asynchronous tests. XCTestExpectation and semaphores. In the case of doing something asynchronous in setUpyou should use the semaphore technique:. Note, for that to work, this onDone block cannot run on the main thread or else you'll deadlock. This is a very inefficient pattern, but depending upon how overwriteDatabase was implemented, it might be necessary. Note, only use this pattern if you know that onDone block runs on the main thread otherwise you'll have to do some synchronization of finished variable.

Rather than using semaphores or blocking loops, you can use the same waitForExpectationsWithTimeout:handler: function you use in your async test cases.

Learn more. Ask Question. Asked 5 years ago. Active 8 months ago.

xctest setup

Viewed 23k times. It also has XCTestException's which let me write async tests. Also great! Is there a way to have setUp wait until my database is ready before it runs tests? Eric Aya Brett Elliot Brett Elliot 1 1 gold badge 5 5 silver badges 6 6 bronze badges.

If you search stack overflow for "[ios] asynchronous unit test" you'll see a ton of answers with not only the XCTestExpectation not XCTestException technique, but also the semaphore technique.

You can probably use the semaphore technique for your async database code though you haven't shared how you're doing this database stuff so we can't be more specific than that.By using our site, you acknowledge that you have read and understand our Cookie PolicyPrivacy Policyand our Terms of Service. The dark mode beta is finally here. Change your preferences any time. Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information.

I'd like to think that I understand the idea of inheritance but apparently I don't because I'm confused as to why there a setup method in XCTestCase if XCTest provides the setup method in its class?

It doesn't have its own implementation of them. They're just do-nothing methods, anyway. They're only defined so that we can override them. This is an example of the Template Method design pattern. This potentially allows us to define new ways of defining test suites other than XCTestCase subclasses, while still integrating with the XCTest framework. You can override the superclass's implementation completely or you can call super. In tests, it's common for an XCTestCase subclass to override setUp to add common setup actions for that class, whereas the superclass's implementation will execute common setup actions for your whole suite.

For example, one XCTestCase subclass will have a setUp method which launches the app, and a subclass of that class will have a setUp method which calls its superclass setup and then initializes the area under test in that class.

xctest setup

In a unit test, this could mean creating an object, or in a UI test, this could mean navigating to a particular page in your app. You need to override XCTestCase's setUp when you subclass it if you want something to happen during the setup stage of your tests as it has an empty implementation by default. This enables users of the framework to specify actions to be done at the beginning of each test by overriding the setUp method, which does not require any test invocation logic, instead of having to override methods with other logic in them, which we wouldn't necessarily know about and may not implement correctly or at all when overriding the method.

This model makes setUp a safe place for you to execute code entirely of your choosing, without needing to worry about whether you have broken the entire test framework.

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Learn more. Ask Question. Asked 3 years ago. Active 3 years ago. Viewed 1k times. This method is called before the invocation of each test method in the class.

This method is called after the invocation of each test method in the class. Cosmic Arrows Cosmic Arrows 3, 3 3 gold badges 22 22 silver badges 43 43 bronze badges. Which setup method are you talking about? Active Oldest Votes. XCTest is a base class, with empty setUp and tearDown methods. Jon Reid Jon Reid You can override a method in a subclass to add more functionality to what the superclass has.

Oletha Oletha 5, 1 1 gold badge 15 15 silver badges 33 33 bronze badges. Sign up or log in Sign up using Google. Sign up using Facebook.Most Xcode project templates now support testing out-of-the-box. Xcode unit tests are contained within an XCTest Case subclass.

By convention, each XCTest Case subclass encapsulates a particular set of concerns, such as a feature, use case, or flow of an application. Dividing up tests logically across a manageable number of test cases makes a huge difference as codebases grow and evolve. Since XCTest Case is not intended to be initialized directly from within a test case definition, shared properties initialized in set Up are declared as optional var s in Swift.

XCTest comes with a number of built-in assertions, but one could narrow them down to just a few essentials:. To be entirely reductionist, all of the XCTest assertions come down to a single, base assertion:. If the expression evaluates to truethe test passes. Otherwise, the test fails, printing the format ted message. Although a developer could get away with only using XCTAssertthe following helper assertions provide some useful semantics to help clarify what exactly is being tested.

When possible, use the most specific assertion available, falling back to XCTAssert only in cases where it better expresses the intent. When specifically testing whether two DoubleFloator other floating-point values are equal, use XCTAssert[Not]Equal With Accuracyto account for any issues with floating point accuracy :.

XCTFail is most commonly used to denote a placeholder for a test that should be made to pass. It is also useful for handling error cases already accounted by other flow control structures, such as the else clause of an if statement testing for success. New in Xcode 6 is the ability to benchmark the performance of code :. The test output shows the average execution time for the measured block as well as individual run times and standard deviation:.

Performance tests help establish a baseline of performance for hot code paths. Sprinkle them into your test cases to ensure that significant algorithms and procedures remain performant as time goes on. Perhaps the most exciting feature added in Xcode 6 is built-in support for asynchronous testing, with the XCTest Expectation class. Now, tests can wait for a specified length of time for certain conditions to be satisfied, without resorting to complicated GCD incantations.

To make a test asynchronous, first create an expectation with expectation With Description :. Then, at the bottom of the method, add the wait For Expectations With Timeout method, specifying a timeout, and optionally a handler to execute when either the conditions of your test are met or the timeout is reached a timeout is automatically treated as a failed test :.

Now, the only remaining step is to fulfill that expecation in the relevant callback of the asynchronous method being tested:. Always call fulfill at the end of the asynchronous callback—fulfilling the expectation earlier can set up a race condition where the run loop may exit before completing the test. If the test has more than one expectation, it will not pass unless each expectation executes fulfill within the timeout specified in wait For Expectations With Timeout.

With first-class support for asynchronous testing, Xcode 6 seems to have fulfilled all of the needs of a modern test-driven developer. Well, perhaps save for one: mocking. Mocking can be a useful technique for isolating and controlling behavior in systems that, for reasons of complexity, non-determinism, or performance constraints, do not usually lend themselves to testing. Examples include simulating specific networking interactions, intensive database queries, or inducing states that might emerge under a particular race condition.

There are a couple of open source libraries for creating mock objects and stubbing method calls, but these libraries largely rely on Objective-C runtime manipulation, something that is not currently possible with Swift. In Swift, classes can be declared within the definition of a function, allowing for mock objects to be extremely self-contained. Just declare a mock inner-class, override and necessary methods:.


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