Implementing the Location struct
In the previous section, we added a struct to hold information about the location. We will now add tests to make sure that Location has the required properties and initializer.
The tests could be added to ToDoItemTests, but they are easier to maintain when the test classes mirror the implementation classes/structs. So, we need a new test case class.
Open Project Navigator, select the ToDoTests group, and add a unit test case class with the name LocationTests. Make sure that you go to iOS | Source | Unit Test Case Class because we want to test the iOS code and Xcode sometimes navigates to OS X | Source. Choose to store the file in the Model folder we created previously.
Set up the editor to show LocationTests.swift on the left-hand side and Location.swift in the Assistant Editor on the right-hand side. In the test class, add @testable import ToDo, and remove the testExample() and testPerformanceExample() template tests.
Adding a coordinate property
To drive the...
