Getting Started with Cucumber for Elixir
View SourceCucumber for Elixir allows you to write executable specifications using natural language that bridges the gap between technical and non-technical stakeholders.
Overview
The Cucumber framework allows you to write tests in a natural language format using Gherkin syntax. This approach enables:
- Behavior-driven development (BDD)
- Clear documentation of application behavior
- Tests that serve as living documentation
Installation
Add cucumber
to your mix.exs
dependencies:
def deps do
[
{:cucumber, "~> 0.1.0"}
]
end
Quick Start
1. Create a Feature File
Feature files use the Gherkin syntax and should be placed in test/features/
with a .feature
extension.
# test/features/user_authentication.feature
Feature: User Authentication
Background:
Given the application is running
Scenario: User signs in with valid credentials
Given I am on the sign in page
When I enter "user@example.com" as my email
And I enter "password123" as my password
And I click the "Sign In" button
Then I should be redirected to the dashboard
And I should see "Welcome back" message
2. Create a Test Module
Create a test module that uses the Cucumber
macro:
defmodule UserAuthenticationTest do
use Cucumber, feature: "user_authentication.feature"
# Step definitions
defstep "the application is running" do
# Setup code here
:ok
end
defstep "I am on the sign in page", context do
# Navigate to sign in page
Map.put(context, :current_page, :sign_in)
end
defstep "I enter {string} as my email", context do
email = List.first(context.args)
# Code to enter email
Map.put(context, :email, email)
end
defstep "I enter {string} as my password", context do
password = List.first(context.args)
# Code to enter password
Map.put(context, :password, password)
end
defstep "I click the {string} button", context do
button_text = List.first(context.args)
# Code to click button
{:ok, %{clicked: button_text}}
end
defstep "I should be redirected to the dashboard", context do
# Assertions for redirection
assert context.current_page == :dashboard
:ok
end
defstep "I should see {string} message", context do
message = List.first(context.args)
# Assertion for message
assert_text(message)
:ok
end
end
3. Run Your Tests
Run your tests using the standard mix test command:
mix test test/lib/user_authentication_test.exs
Next Steps
For more detailed information about the Cucumber for Elixir framework, check out these guides:
- Feature Files - Learn how to write feature files with Gherkin syntax
- Step Definitions - Learn how to implement step definitions
- Error Handling - Understanding error reporting and debugging
- Best Practices - Best practices and examples