In the previous chapter, we wrote a stub for CLGeocoder. Now, we will write a test that asserts that the geocoder built into CoreLocation works as we expect it to. The fetching of coordinates from a geocoder is asynchronous. This means that we have to write a test that can deal with asynchronous interfaces.
Let's first structure the files a bit in the Project Navigator of Xcode. Select all the controller files in the main target (ItemListViewController.swift, ItemListDataProvider.swift, ItemCell.swift, DetailViewController.swift, and InputViewController.swift), and press ctrl + click to create a group from the selection. Let's call this group Controller. Do the same with the corresponding test cases ...