Ordering unit test using XCTest in Xcode 6

Question

I would like to know if there is any way to tell Xcode to run unit tests in a specified order. I mean not in a same XCTestCase class file, but between all the class file.

For example I want to run the SitchozrSDKSessionTest before running SitchozrSDKMessageTest.

I looked over few threads on stack or on Apple documentation and I haven't found something helpful.

Thanks for your help.

Solution 1

It's all sorted alphabetically (classes and methods). So when You need some tests running last, just change the name of Class or Method (for (nasty) example by prefixing 'z_').

So...You have Class names:

MyAppTest1
  -testMethodA
  -testMethodB
MyAppTest2
  -testMethodC
  -testMethodD

and they run in this order. If you need to run MyAppTest1 as second, just rename so it's name is alphabetically after MyAppTest2 (z_MyAppTest1) and it will run (same for method):

MyAppTest2
  -a_testMethodD
  -testMethodC
z_MyAppTest1
  -testMethodA
  -testMethodB

Also please take the naming as example :)

Solution 2

It is true that currently (as of Xcode 7), XCTestCase methods are run in alphabetical order, so you can force an order for them by naming them cleverly. However, this is an implementation detail and seems like it could change.

A (hopefully) less fragile way to do this is to override +[XCTestCase testInvocations] and return your own NSInvocation objects in the order you want the tests run.

Something like:

+ (NSArray *)testInvocations
{
    NSArray *selectorStrings = @[@"testFirstThing",
                                 @"testSecondThing",
                                 @"testAnotherThing",
                                 @"testLastThing"];

    NSMutableArray *result = [NSMutableArray array];
    for (NSString *selectorString in selectorStrings) {
        SEL selector = NSSelectorFromString(selectorString);
        NSMethodSignature *methodSignature = [self instanceMethodSignatureForSelector:selector];
        NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:methodSignature];
        invocation.selector = selector;
        [result addObject:invocation];
    }
    return result;
}

Of course, the downside here is that you have to manually add each test method to this instead of them being picked up automatically. There are a few ways to improve this situation. If you only need to order some of your test methods, not all of them, in your override of +testInvocations, you could call through to super, filter out those methods that you've manually ordered, then tack the rest on to the end of the array you return. If you need to order all the test methods, you could still get the result of calling through to super and verify that all of the automatically picked up methods are covered by your manually created, ordered result. If not, you could assert, causing a failure if you've forgotten to add any methods.

I'm leaving aside the discussion of whether it's "correct" to write tests that must run in a certain order. I think there are rare scenarios where that makes sense, but others may disagree.

Solution 3

its ordered by function names letter orders, doesn't matter how you order it in your code. e.g.:

-(void)testCFun(){};
-(void)testB2Fun(){};
-(void)testB1Fun(){};

the actual execute order is :

1. testB1Fun called
2. testB2Fun called
3. testCFun called

Solution 4

In addition to andrew-madsen's answer:
I created a 'smart' testInvocations class method which searches for selectors starting with "test" and sorts them alphabetically.
So you don't have to maintain an NSArray of selector names separately.

#import <objc/runtime.h>

+ (NSArray <NSInvocation *> *)testInvocations
{
    // Get the selectors of this class
    unsigned int mc = 0;
    Method *mlist = class_copyMethodList(self.class, &mc);
    NSMutableArray *selectorNames = [NSMutableArray array];
    for (int i = 0; i < mc; i++) {
        NSString *name = [NSString stringWithFormat:@"%s", sel_getName(method_getName(mlist[i]))];
        if (name.length > 4
            && [[name substringToIndex:4] isEqualToString:@"test"]) {
            [selectorNames addObject:name];
        }
    }

    // Sort them alphabetically
    [selectorNames sortUsingComparator:^NSComparisonResult(NSString * _Nonnull sel1, NSString * _Nonnull sel2) {
        return [sel1 compare:sel2];
    }];

    // Build the NSArray with NSInvocations
    NSMutableArray *result = [NSMutableArray array];
    for (NSString *selectorString in selectorNames) {
        SEL selector = NSSelectorFromString(selectorString);
        NSMethodSignature *methodSignature = [self instanceMethodSignatureForSelector:selector];
        NSInvocation *invocation = [NSInvocation invocationWithMethodSignature:methodSignature];
        invocation.selector = selector;
        [result addObject:invocation];
    }
    return result;
}

Footnote: It's considered bad practice making your unit tests depend on eachother

Solution 5

For you exemple you can just rename the tests files on your project like this :

SitchozrSDKSessionTest -> t001_SitchozrSDKSessionTest
SitchozrSDKMessageTest -> t002_SitchozrSDKMessageTest

Xcode treat the files using alphabetic order.

View more solutions

Comments

[BoilingLime]

I don't want to order test in a specific test class file but but the class files themselves.

[NSRover]

this is very useful! where did you get this information from? is it documented?

[Nick Entin]

That's interesting. Do you know if those methods actually need to be named as "testXXX" ones? If not, probably you don't need to filter anything special - just add to the "[super]" array your methods... P.S. I have following problem: I need to create, process and delete some records. And I want to measure performance of each stage. But if put all those routines in same method, I get "Can only record one set of metrics per test method". So I hope to split those to 3 different methods, still I need to ensure order of execution.

[Andrew Madsen]

@NickEntin: No, I don't think they need to be prefixed with "test". That's used by XCTestCase to automatically pick up on methods for its implementation of +testInvocations, but if you're providing the invocations yourself, you should be able to name them however you'd like. I still like the "testXXX" convention, myself. Regarding your problem, you should ask a separate question and link it here.

[sbarow]

Isn't this what the standard testInvocations does? i.e sort them alphabetically and run them?

[fede1608]

NSInvocation is unavailable in Swift, any workaround?

[Andrew Madsen]

@fede1608: This method has to return an array of NSInvocations. That's just how it works. So, I think the only non-ugly workaround is to implement this in Objective-C. You could presumably make the XCTestCase subclass itself, and this method, be ObjC, then use a Swift extension to add the actual test cases.

[jimpic]

it should be noted that this is not true anymore in Xcode 8

[Tina Zh]

Xcode 8.2.1: work. Please make attention: you should rename classes, not files.

[Evan R]

Using Xcode 8.2.1 and attempting your solution, I'm seeing one of my test methods being called before -testInvocations is called when I run my test suite for the test class. Have you tried this in 8.2.1?

[Andrew Madsen]

@EvanR: I have not tested this in 8.2.1. If what you're describing is actually happening, that sounds worth filing a radar for.

[Greg Hilston]

I wish @BoilingLime 's comment had attention back in '14