Checking code coverage

Xcode includes a convenient feature for you to check the coverage of your tests. The test coverage metric measures how much of your code is covered by the unit tests already implemented in your project. This metric gives you confidence that any code changes you made will be adequately tested. Even though you may not find it too useful to have a perfect test coverage, you generally want to maintain a high percentage of code coverage throughout your development. In this way, it is less likely for you to break any code as you make progress in adding incremental enhancements to your project.