Cucumber - Features and feature files

Cucumber - Features and feature files

A feature file is a definition, a specification of sorts, that states clearly a number of scenarios that must be tested. It’s written in a lingo known as humourously as ‘Gherkin’.

The basic format of a Gherkin feature file

Feature: this is a feature

  Scenario: this is a scenario
    Given X
    And Y
    When A
    And B
    Then Z


  Scenario Outline: This is another scenario
    Given X
    And Y
    When something is <word>
    Then check for <number>
    
    Examples:
    | word | number |
    | ant  | 1      |
    | bug  | 3      |
    | car  | 5      |

A lot has been writted about Gherkin and Cucumber tests, and there’s little reason to recite it all here. What doesn’t seem to be covered is a few golden rules that make the features make more sense and keep them sane.

• only Capitalise Given / When / Then - it makes it more readable

• give useful names to the scenarios, as this appears in a lot of places

• use proper names that fit the business requirements in the feature definitions as it makes it must easier to review the features

• avoid words like click, open, touch, enter, and so on. these things below hidden away in the step definitions that exercise the feture

Given

Given sets up the known state for the start of the test

When

When describes the action or actions you must take for the start to get to the point you need to be to make an assertion

Then

Then is a test, a check, an assertion.