Cucumber Testing Explained

In few recent decades, Cucumber has become a popular tool as a BDD tool, allowing user to write test cases in a simple, human-readable format. Also, it has bridged the gap between technical and non-technical stakeholders by enabling collaboration by simplifying the test specifications.

Key Components of Cucumber

Cucumber tests consist of 2 main components:

1. feature files.
2. step definitions.

These components work together to define, automate, and execute test scenarios in a BDD framework. Let's explore each component in detail:

1. Feature Files

Feature files in Cucumber are written in Gherkin, a plain-text language that uses keywords to describe the behavior of an application. These files serve as executable specifications and are typically written collaboratively by stakeholders, including developers, testers, and business analysts.

Example of a feature file (calculator.feature):

Feature: Calculator Addition
  As a user,
  I want to add two numbers using a calculator,
  So that I can get the correct sum.

  Scenario: Add two numbers
    Given I have entered 50 into the calculator
    And I have entered 70 into the calculator
    When I press add
    Then the result should be 120 on the screen

2. Step Definitions

Step definitions map each step in the feature file to actual automation code written in JavaScript using Cucumber.js. These steps interpret the Gherkin syntax and perform actions on the application under test.

Example of step definitions (calculator-steps.js):

const {Given, When, Then} = require("cucumber");
const assert = require("assert");
const Calculator = require("../src/calculator");

let calculator;
let result;

Given("I have entered {int} into the calculator", function (number) {
  calculator = new Calculator();
  calculator.enterNumber(number);
});

When("I press add", function () {
  result = calculator.add();
});

Then("the result should be {int} on the screen", function (expected) {
  assert.strictEqual(result, expected);
});

What are advantages of Cucumber Testing ?

• Collaboration: Facilitates collaboration between technical and non-technical stakeholders through understandable feature files.
• Clarity: Provides clear and concise specifications using Gherkin syntax.
• Reusability: Promotes reuse of step definitions across different scenarios, improving maintainability.
• Automation: Integrates easily with automation frameworks and CI/CD pipelines for continuous testing.

What are some alternatives to Cucumber Testing ?

While Cucumber is widely used for BDD and Gherkin-based testing, several alternatives offer similar functionalities tailored to different preferences and project requirements:

1. JBehave JBehave is a Java-based framework that supports BDD with a focus on behavior-driven development for Java applications. It uses plain-text stories written in a business-readable language.

2. SpecFlow SpecFlow is a BDD framework for .NET applications, providing integration with Visual Studio and offering support for writing specifications in Gherkin syntax.

3. Behat Behat is a PHP framework for BDD that facilitates communication between stakeholders through feature files written in Gherkin and step definitions in PHP.

4. Robot Framework Robot Framework is a generic open-source automation framework for acceptance testing and BDD. It supports keyword-driven testing approaches and has libraries for various test automation needs.

5. Karate Karate is an open-source tool that combines API test-automation, mocks, performance testing, and UI automation into a single, unified framework. It uses a BDD syntax for writing tests.

6. Gauge Gauge is an open-source test automation framework that supports the creation of readable and reusable tests. It uses Markdown-like syntax for writing specifications and supports multiple programming languages.

Conclusion

Cucumber testing revolutionizes software testing by enabling teams to collaborate effectively through executable specifications written in Gherkin. By bridging communication gaps between stakeholders and automating tests with reusable step definitions, Cucumber enhances the reliability, maintainability, and scalability of software applications. Incorporating Cucumber into BDD practices empowers teams to deliver high-quality software that meets business requirements and user expectations seamlessly.

FAQ about Cucumber Testing

1. What is Cucumber testing used for?

• Cucumber is used for Behavior-Driven Development approach to write acceptance tests in a human-readable format.

2. How does Cucumber enhance collaboration in software development?

• Cucumber's feature files allow stakeholders to define application behavior together, ensuring clarity and alignment.

3. Can Cucumber integrate with existing testing frameworks?

• Yes, Cucumber can integrate with popular testing frameworks like Mocha, Jasmine, and Jest for automated testing.

4. What are the key components of a Cucumber test scenario?

• A Cucumber scenario consists of a feature file written in Gherkin and corresponding step definitions written in JavaScript.

5. How does Cucumber handle test data and scenarios?

• Cucumber manages test data through scenario outlines and examples tables in feature files, supporting data-driven testing.

6. Is Cucumber suitable for Agile and DevOps environments?

• Yes, Cucumber supports Agile and DevOps practices by enabling continuous testing and collaboration among cross-functional teams.