Green - example 1

Now, the method returns an empty string. This should be enough to make the test compile. Run the test. The test fails. But this time, it's not because the code we've written does not compile, but due to the failed assertion instead. This is not a surprise because an empty string isn't equal to "This Is A Test Headline". Following the TDD workflow, we need to go back to the implementation and add the simplest code that makes the test pass.

In ViewController, change makeHeadline(from:) to read as follows:

func makeHeadline(from string: String) -> String { 
  return "This Is A Test Headline" 
} 

This code is stupid and wrong, but it is the simplest code that makes the test pass. Run the tests to make sure that this is actually the case.

Even though the code we just wrote is useless for the feature we are trying to implement, it still has value for us, the developers. It tells us that we need another test.