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.

These 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 the Project navigator, select the ToDoTests group, and add a unit test case class called LocationTests. Make sure that you go to iOS | Source | Unit Test Case Class since we want to test the iOS code, and Xcode sometimes navigates to OS X | Source.

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

The location of a to-do item will be used in the app to show...