GoogleMock - Xcode

About

This project consists of an integration of the GoogleMock library to Apple's Xcode IDE.

Since version 5, Xcode provides a nice way to write unit tests with the XCTest framework.
Unit tests written with XCTest are integrated to the IDE, providing visual feedback when running tests. They are also integrated with the different build toolchains, like xcodebuild or Facebook's xctool.

It was specifially designed for Objective-C, writing unit tests for other languages (such as C++) is not so great with XCTest. Of course, this is possible using Objective-C++, but writing an Objective-C class for each C++ test case leads to some undesired overhead.

GoogleMock is nice unit testing library for C++. The only issue is that it does not integrate well with Xcode, as does XCTest.
This mean the IDE won't provide visual feedback for the unit tests written with GoogleMock, and you'll have to look at the console output to inspect any failed test.

So this project fixes this issue by bridging GoogleMock to XCTest.

Implementation details

XCTest works by analysing test classes at runtime, thanks to Objective-C dynamic nature.
Basically, when the test bundle is loaded, it will look for all classes extending XCTestCase, and look for methods beginning with the test prefix.

If such a class is available, it will then create an instance, and launch each test method, reporting the result to the IDE.

This project consists of a framework which has to be linked to the unit test bundle. The framework includes GoogleMock, so you don't have to build it by yourself.

It works by querying each GoogleMock test case. For each one, a specific subclass of XCTestCase will be dynamically created at runtime.
For each test in a test case, an Objective-C method will be created and added to the XCTestCase subclass.

The GoogleMock test cases are then run, reporting the usual output to the console.

Then, as we created new classes compatible with XCTest, it will find them, and run them as usual.
Each method will simply look at the GoogleMock test result, and report the status using XCTest assertions, so we got visual feedback, as if we had written our test cases using XCTest.

Project Configuration

In order to use these features, your unit test bundle needs to be linked to the provided frameworks.

The easiest way to do this is to include the provided Xcode project (GoogleMock.xcodeproj) as a subproject of your own Xcode project, so all targets are available.

Then, from the Build Phases screen of your unit test's target, add the following frameworks to the Target Dependancies step:

• GoogleMock

Adds the same frameworks to the Link Binary With Libraries step, and you're done.
Your unit test bundle is now ready to use GoogleMock.

Writing tests

Writing GoogleMock tests is also straightforward.
Simply include <GoogleMock/GoogleMock.h> to your .cpp file, and write your tests as usual.

For instance:

#include <GoogleMock/GoogleMock.h>

using namespace testing;

TEST( MyTestCase, MyTest )
{
    ASSERT_TRUE( true );
}

In the above example, a subclass of XCTestCase named MyTestCase will be created at runtime, with a test method called testMyTest, so you can easily inspect the results of your GoogleMock tests directly from the Xcode tests tab.

License

The GoogleMock Xcode integration library is released under the terms of the MIT License.

Repository Infos

Owner:			Jean-David Gadina - XS-Labs
Web:			www.xs-labs.com
Blog:			www.noxeos.com
Twitter:		@macmade
GitHub:			github.com/macmade
LinkedIn:		ch.linkedin.com/in/macmade/
StackOverflow:	stackoverflow.com/users/182676/macmade