Selenium vs Cucumber: The Differences and Which to Use

Selenium and Cucumber are two tools that software developers use to execute tests. Both help find bugs in the software before releasing it to customers. However, it may seem difficult for developers to choose between these two tools, especially if they want to use a more advanced BDD (behavior-driven development) framework.

This post is about how these two tools work and how to use them. You’ll also see the differences between selenium vs cucumber, which will help you decide which may work best for your needs.

What Is Cucumber?

Cucumber is a BDD method to develop automated acceptance tests for your software system. We typically implement it with Gherkin syntax (a subset of natural language). Cucumber tests run on the command line and are executed by Cucumber-JVM. You write Cucumber tests using programming languages like Java, Ruby, Python, and JavaScript, but you can also write them in a non-programming language like Markdown.

Cucumber is a Ruby library that predefines the steps of an automated software test. It’s written with domain-specific language (DSL) that’s easy to read and maintain. The resulting code will be readable by programmers and nontechnical people, making it unique among automated testing frameworks.

Cucumber uses “steps” as actions in the test. These steps are short sentences in plain English describing the user’s action and what they expect to get. It defines steps for a feature or unit. A feature represents a screen or piece of functionality that the user can interact with, and the unit is a small chunk of code that belongs to one feature.

You write Cucumber tests using plain English syntax such as “The form should be invalid” or “User should see this error message.”

What Is Selenium?

Selenium is an open-source framework that allows you to write browser-based automation scripts on top of your application’s UI interactions. It’s a WebDriver framework for automating browser-based interactions with web applications. This allows you to script your website’s behavior and end-to-end test workflows, leveraging the power of various browsers (including those on mobile devices) integrated into Selenium agents. For example, you can write a script to run an application on your website automatically, validate form input, and test that you’re returning the correct results to your application.

Selenium allows you to simulate and test a browser’s interactions with your website, interact with the application being tested, run tests on various browsers, and install extensions that can perform various tasks. It’s a library for web applications such as Firefox or Internet Explorer on multiple operating systems. It’s free software, which you should be able to use in commercial projects too. Selenium has two components: the selenium IDE, which lets you record scripts for playback, and the Selenium WebDriver, which facilitates browser automation outside the IDE or command line.

What Are the Differences?

You write Cucumber tests in plain English, which is easier to read and write than Selenium tests.

Cucumber is written in ruby, while Selenium is written in Java.

You run Cucumber tests manually at the beginning of the project before using Selenium. Still, you may also need to write Cucumber tests separately from Selenium tests if you want them to run automatically.

When using Cucumber independently or with Gherkin, you can automate your test cases later by tools such as Rake in a build process where they will run even before integrating the end users into the system. You must automate Selenium tests at the end of the process.

When Should I Use Cucumber Instead of Selenium?

Here are some situations where you might choose Cucumber over Selenium. You might want your tests written in plain English, so everyone on your team understands them. This means you can use it for business requirements but also UI specifications.

You may also want to use your tests for automated build or continuous integration, especially unit tests. In such situations, you can write the test cases in classical Cucumber syntax and then have the build script run them. You may also use other tools like Jasmine (Java) or RSpec & Behat to ensure that continuous integration is well-written and covers them.

Below is an example of a Cucumber test for the login feature:

Feature: Login
  Scenario: Successful login with correct credentials
    Given I am on the login page
    When I enter the correct username and password
    Then I should be logged in
    And I should see the home page
  Scenario: Unsuccessful login with incorrect credentials
    Given I am on the login page
    When I enter an incorrect username and password
    Then I should see an error message
    And I should be on the login page

When Should I Use Selenium Instead of Cucumber?

Selenium is more suitable for solving straightforward coding problems. It’s quite flexible, and it makes possible the automation of browser-based regression testing, cross-browser and cross-platform testing, performance testing, stress testing, and so forth.

Below is an example of a Selenium test for testing the login functionality:

import org.junit.Test; 
import org.openqa.selenium.By; 
import org.openqa.selenium.WebDriver; 
import org.openqa.selenium.WebElement;
import org.openqa.selenium.chrome.ChromeDriver; 
import static org.junit.Assert.assertEquals; 
import java.util.concurrent.TimeUnit; 
import org.openqa.selenium.By; 
import org.openqa.selenium.WebDriver; 
import org.openqa.selenium.WebElement; 
import org.openqa.selenium.chrome.ChromeDriver; 

public class LoginTest {  
 private WebDriver driver;  
 @Before
  public void setUp() {
  System.setProperty("webdriver.chrome.driver", "path/to/chromedriver");
  driver = new ChromeDriver();
  driver.manage().timeouts().implicitlyWait(30, TimeUnit.SECONDS);
  }
 @After
  public void tearDown() {
  driver.quit();
  }
@Test
public void testLogin() {
    driver.get("http://www.example.com/login");
    driver.findElement(By.id("username")).sendKeys("test");
    driver.findElement(By.id("password")).sendKeys("test");
    driver.findElement(By.id("login")).click();
    assertEquals("http://www.example.com/dashboard", driver.getCurrentUrl());
} 

@Test
public void testInvalidLogin() {
    driver.get("http://www.example.com/login");
    driver.findElement(By.id("username")).sendKeys("test");
    driver.findElement(By.id("password")).sendKeys("wrongpassword");
    driver.findElement(By.id("login")).click();
    assertEquals("http://www.example.com/login?error=1", driver.getCurrentUrl());
}

Selenium VS Cucumber: How They’re Used Together

To use Selenium and Cucumber together, you should segment your project into several sections that can be used for both tests. For example, if you’re developing a web app, you could split the project into an API and a front-end portion, allowing you to use Cucumber to test the API. This way, Cucumber can test both the business logic of your program and some of its user-facing elements (since you’re now separating portions from another).

There can be situations where Selenium would not be enough to support some activities, such as checking conformity to language or framework-specific standards. In such cases, you can use Cucumber as a layer on top of Selenium, making it possible for nontechnical users in the product development team to test the code. This is because Cucumber is a language-independent framework.

What Are the Advantages of Cucumber?

Cucumber allows developers and nontechnical stakeholders to collaborate on code using natural language. With Cucumber, you write in plain English what your application should do rather than writing in code. This feature makes using Cucumber beneficial for teams with a hybrid of technical and nontechnical members or even those without coding experience.

Because Cucumber works on top of Gherkin, it’s easy to port the scenario to any programming language. It’s also faster than Selenium. Cucumber supports request-based testing, making it more efficient than Selenium in handling browser-based data flow.

Why Selenium Is More Reliable than Cucumber

Selenium has a native currency of features, enabling you to control browsers wherever they control precisely what happens on each page. The best part about Selenium is that the output looks exactly like what happens on the computer screen (just like an image).

Selenium can be efficient if used correctly and should be your first choice if you want to write tests for web applications. Therefore, we recommend you start with Selenium and learn about Cucumber later.

What Are the Challenges of Using Cucumber?

Cucumber is a pure framework solution. It does not provide built-in functionality for the following:

• Scheduling
• Distributing and running processes in parallel
• Reusing code from one test to the next

If you over-complicate your scenario specifications, separating the scenario from its implementation or the data source being tested by that scenario will be challenging. This leads to complex and large scenarios that are hard to read without prior knowledge of the system under test or without breaking down the scenarios into smaller ones with more readable step definitions.

What Are the Challenges of Using Selenium?

Selenium has a steeper learning curve than Cucumber. It’s challenging to use for business analysts and testers with little or no programming experience.

The other issue with Selenium is that the reports are not as simple to understand as Cucumber’s. You can view Selenium reports on the website while debugging, but they may not be easy to read after complete testing.

Conclusion

Cucumber and Selenium are both excellent tools for automated software testing. Both have their advantages, but the right choice will be the one that best suits your needs. Selenium is excellent for automating web applications, while Cucumber is great for behavior–driven testing. Selenium is an excellent option if you’re looking for a tool to help with your web testing. If you‘re looking for a tool to help with behavior–driven testing, Cucumber is a great option. If you‘re looking for a comprehensive tool that can help with web automation and behavior–driven testing, check out Testim.