Implementing ItemListDataProvider

In the previous section, we created a class to act as the data source and delegate for the item list table view. In this section, we will implement its properties and methods, but we first need a test case class for ItemListDataProvider.

Conducting the first tests

Open Project Navigator and select the ToDoTests group. Add a new Unit Test Case Class and call it ItemListDataProviderTests. Add the @testable import ToDo import statement and remove the two test template methods.

The table view should have two sections--one for unchecked to-do items and the other for checked items. Add the following test to ItemListDataProviderTests:

func test_NumberOfSections_IsTwo() { 
  let sut = ItemListDataProvider() 
  let tableView = UITableView() 
  tableView.dataSource = sut 
   

  let numberOfSections = tableView.numberOfSections 
  XCTAssertEqual(numberOfSections, 2) 
} 

First, we create an instance of ItemListDataProvider, set up the table view, and then we check whether...