Creating the feature file

We begin with writing an example Cucumber feature file.

The Gherkin syntax that’s used to write features is characterized by the three words Given, When, and Then. These are analogous to the Arrange, Act, and Assert sections of all good unit tests, so they should feel familiar.

Let’s jump right in with our feature file and see what happens when we execute the test:

1. Start by adding a new directory, features, with a new features/birthdays.feature file with the following content. It describes a user scenario in which the Birthdays application already supports editing a birthday. Here it is:

   Feature: Editing a birthday
     Scenario: Correcting the year of birth
       Given An existing birthday for "Hercules" on
         "1992-03-04"
       When I navigate to the "/birthdays" page
       And I edit the birthday for &quot...