In this context, it’s worth noting that, like RSpec, Cucumber can be invoked using a Rake task:

(For reasons that escape me, this is sometimes written as rake cucumber:ok.)

All we’ve done so far is write some plain text, so it shouldn’t be surprising that the Cucumber scenarios aren’t yet passing. To get the test suite to green, we need to add a step file that maps the plain-text lines to Ruby code. The step file goes in the features/step_definitions directory; we’ll call it authentication_steps.rb.

     The Feature and Scenario lines are mainly for documentation, but each of the other lines needs some corresponding Ruby. For example, the line  

in the feature file gets handled by the step definition

In the feature, Given is just a string, but in the step file Given is a method that takes a regular expression and a block. The regex matches the text of the line in the scenario, and the contents of the block are the Ruby code needed to implement the step. In this case, ‘‘a user visits the signin page’’ is implemented by  

If this looks familiar, it should: It’s just Capybara, which is included by default in Cucumber step files. The next two lines should also look familiar; the scenario steps

in the feature file are handled by these steps: