Page Object Model in Cypress - Test Execution Trace

Test Overview

This test uses the Page Object Model to separate page structure from test logic. It verifies that a user can log in successfully and see a welcome message.

Test Code - Cypress

Cypress

class LoginPage {
  visit() {
    cy.visit('https://example.com/login')
  }

  fillUsername(name) {
    cy.get('#username').clear().type(name)
  }

  fillPassword(password) {
    cy.get('#password').clear().type(password)
  }

  submit() {
    cy.get('button[type="submit"]').click()
  }
}

describe('Login Test with POM', () => {
  const loginPage = new LoginPage()

  it('should log in successfully and show welcome message', () => {
    loginPage.visit()
    loginPage.fillUsername('testuser')
    loginPage.fillPassword('Password123')
    loginPage.submit()
    cy.get('#welcome-message').should('contain.text', 'Welcome, testuser!')
  })
})

Execution Trace - 7 Steps

Step	Action	System State	Assertion	Result
1	Test starts	Cypress test runner initialized	—	PASS
2	Browser opens and navigates to 'https://example.com/login'	Login page is displayed with username and password fields	URL is 'https://example.com/login'	PASS
3	Finds username input field with selector '#username' and types 'testuser'	Username field contains 'testuser'	Username input value is 'testuser'	PASS
4	Finds password input field with selector '#password' and types 'Password123'	Password field contains 'Password123'	Password input value is 'Password123'	PASS
5	Finds submit button with selector 'button[type="submit"]' and clicks it	Form submitted, page processes login	—	PASS
6	Finds element with selector '#welcome-message' and checks it contains text 'Welcome, testuser!'	Welcome message is visible on the page	Text content includes 'Welcome, testuser!'	PASS
7	Test ends	Test completed successfully	—	PASS

Failure Scenario

Failing Condition: Welcome message element '#welcome-message' is not found or text does not match

Execution Trace Quiz - 3 Questions

What does the test verify after submitting the login form?

A That the welcome message contains the username

B That the login page reloads

C That the password field is cleared

D That the submit button is disabled

Key Result

Using the Page Object Model helps keep tests clean and easy to maintain by separating page details from test steps.

Practice

1. What is the main purpose of using the Page Object Model in Cypress testing?

easy

A. To write tests without any assertions

B. To avoid using selectors in tests

C. To speed up the browser loading time

D. To organize page interactions into reusable classes

Solution

1. Step 1: Understand the role of Page Object Model

   The Page Object Model (POM) organizes web page elements and actions into classes to reuse code easily.

2. Step 2: Identify the main benefit in Cypress tests

   Using POM makes tests easier to write, read, and maintain by grouping page logic separately from test logic.

3. Final Answer:

   To organize page interactions into reusable classes -> Option D

4. Quick Check:

   Page Object Model = reusable page classes [OK]

Hint: POM groups page actions into classes for reuse [OK]

Common Mistakes:

• Thinking POM speeds up browser loading
• Believing POM removes need for assertions
• Assuming POM avoids selectors entirely

2. Which of the following is the correct way to define a method inside a Cypress Page Object class to click a button with selector button.submit?

easy

A. clickSubmit() { cy.get('button.submit').click(); }

B. clickSubmit() => { cy.get('button.submit').click(); }

C. function clickSubmit() { cy.get('button.submit').click(); }

D. clickSubmit: function() { cy.get('button.submit').click(); }

Solution

1. Step 1: Recognize class method syntax in JavaScript

   Inside a class, methods are defined as methodName() { ... } without the function keyword or arrow syntax.

2. Step 2: Match the correct syntax for Cypress command

   The method should call cy.get('button.submit').click(); inside the method body.

3. Final Answer:

   clickSubmit() { cy.get('button.submit').click(); } -> Option A

4. Quick Check:

   Class method syntax = clickSubmit() { cy.get('button.submit').click(); } [OK]

Hint: Class methods use name() { } syntax, no function keyword [OK]

Common Mistakes:

• Using arrow functions inside class methods incorrectly
• Adding 'function' keyword inside class method
• Using object literal syntax inside class

3. Given this Page Object class snippet:

class LoginPage {
  visit() {
    cy.visit('/login')
  }
  enterUsername(name) {
    cy.get('#username').type(name)
  }
  enterPassword(pass) {
    cy.get('#password').type(pass)
  }
  submit() {
    cy.get('button[type=submit]').click()
  }
}

What will happen when the test calls:
const page = new LoginPage(); page.visit(); page.enterUsername('user1'); page.enterPassword('pass1'); page.submit();

medium

A. The login page loads, username and password are typed, and submit button is clicked

B. Only the login page loads, but no typing or clicking happens

C. Syntax error because methods are not async

D. The test fails because selectors are incorrect

Solution

1. Step 1: Analyze method calls in sequence

   The test creates a LoginPage object and calls methods to visit the page, type username and password, then click submit.

2. Step 2: Confirm Cypress commands are correct

   Selectors like #username, #password, and button[type=submit] are valid and commands are chained properly.

3. Final Answer:

   The login page loads, username and password are typed, and submit button is clicked -> Option A

4. Quick Check:

   Method calls execute Cypress commands in order [OK]

Hint: Methods run Cypress commands sequentially as called [OK]

Common Mistakes:

• Thinking Cypress commands need async/await
• Assuming selectors are invalid without checking
• Believing only visit() runs without chaining

4. You have this Page Object method:

login(username, password) {
  cy.get('#user').type(username)
  cy.get('#pass').type(password)
  cy.get('button.login').click()
}

But your test calls cy.visit('/login') before login(), yet fails because the username input is not found. What is the likely problem?

medium

A. The click() command must come before typing

B. The selector #user is incorrect or outdated

C. The method should use cy.find() instead of cy.get()

D. You forgot to call cy.visit() before login

Solution

1. Step 1: Identify cause of element not found error

   If the username input is not found, the selector #user might be wrong or changed on the page.

2. Step 2: Evaluate other options

   While missing cy.visit() can cause failure, the question states the failure is specifically about the username input not found, pointing to selector issue.

3. Final Answer:

   The selector #user is incorrect or outdated -> Option B

4. Quick Check:

   Element not found = wrong selector [OK]

Hint: Element not found usually means wrong selector [OK]

Common Mistakes:

• Assuming cy.find() fixes selector issues
• Thinking click() must come before typing
• Ignoring the need to visit page first

5. You want to create a Page Object for a form with multiple input fields and a submit button. Which approach best follows Cypress Page Object Model best practices?

hard

A. Use global variables for selectors and call Cypress commands directly in tests

B. Write all test steps directly inside the test without any class or methods

C. Create a class with methods for each field interaction and a submit method, using clear selectors

D. Create one method that types all fields and clicks submit without separate methods

Solution

1. Step 1: Understand POM best practices

   Best practice is to create a class that groups page elements and actions into clear, reusable methods with good selectors.

2. Step 2: Compare options

   Writing all steps in tests or using global variables reduces reusability and clarity. One big method reduces flexibility and readability.

3. Final Answer:

   Create a class with methods for each field interaction and a submit method, using clear selectors -> Option C

4. Quick Check:

   Clear methods + selectors = POM best practice [OK]

Hint: Use classes with clear methods for each page action [OK]

Common Mistakes:

• Putting all steps directly in tests
• Using global selectors without encapsulation
• Combining all actions into one big method