Stack Overflow for Teams is a private, secure spot for you and your coworkers to find and share information. I launch the application once with the solution provided here: XCTestCase not launching application in setUp class method.
The XCTest documentation has a class tearDown method, but when I try to use it - it doesn't have access to the application anymore? This is all I get when I am in the tearDown method and so it can't access any elements on the application anymore:.
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One is at the individual test case level. The other is at the suite level. Just override the class versions to get the entire suite:. Learn more. Asked 2 years, 8 months ago. Active 2 years, 8 months ago. Viewed 1k times. I am using xcode 8. I launch the application once with the solution provided here: XCTestCase not launching application in setUp class method In the tearDown method, I want to logout of the application.
I only want to do this once. After all of the tests in the current XCTestCase, thanks for the clarification. Active Oldest Votes. Titouan de Bailleul Titouan de Bailleul Thank you!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.A test case is a group of related test methods, with optional setup and teardown before and after tests are run.Swift iOS Unit Testing Tutorial
Measures the performance of a block of code, optionally deferring the starting 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?
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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. 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. Have you tried using Quick? What has your experience been? You can view the sourcecode for this post on Github here. Enjoy the article? Natasha The Robot Currently learning Newsletter Jobs try!
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:. 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. 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.
I'm surprised that your database library doesn't have a synchronous feature, because that's very common in database libraries. Rob, I edited my question to show exactly what I'm looking for. What I don't know is how to keep the tests from running until setUp is done. Again, no such thing as XCTestException. It's XCTestExpectation.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.
WWDC19: Getting Started with Test Plan for XCTest
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. 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.
Sponsor Hacking with Swift and reach the world's largest Swift community! Articles Learn Start Here. Start Here.Watch on YouTube. XCTest, similarly to JUnit, invokes each test method on a separate instance of the test case. To illustrate with an example, imagine that you have ten test methods, the XCTest framework will instantiate ten instances of the test case class and invoke only one of the methods per instance.
We believe this is a good design choice, as by running the test methods in separate instances we can avoid sharing state between tests.
We normally use constructor injection. If we create a class as a property in the class scope, we would have to use property injection to be able to configure the instance for each test.
We want to test the whole lifecycle of the system under test instance, to guarantee there are no issues when it's removed from memory.
We could achieve this with the setUp approach, but to test the whole lifecycle we would also need to set it to nil in the tearDown. By creating the instance in the test method scope, we guarantee its lifecycle is tested within the method since the instance will be freed automatically.
It would take more lines of code to do the same thing and, in our opinion, it would negatively impact the design of the test and the production code e. We would like you to be proactive and think about the problems you're facing so you find the best solution for you.
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