cypress.config.js settings - Build an Automation Script

Verify Cypress configuration settings are applied correctly

Preconditions (2)

Step 1: Open cypress.config.js file

Step 2: Set baseUrl to 'https://example.com'

Step 3: Set defaultCommandTimeout to 10000 milliseconds

Step 4: Set viewportWidth to 1280 and viewportHeight to 720

Step 5: Save the configuration file

Step 6: Write a test that visits the baseUrl

Step 7: Check that the viewport size is 1280x720

Step 8: Check that the page URL is 'https://example.com/'

✅ Expected Result: The test runs successfully using the settings from cypress.config.js: baseUrl is used for visit, viewport size is set to 1280x720, and commands respect the default timeout.

Automation Requirements - Cypress

Assertions Needed:

Verify the page URL matches the baseUrl from config

Verify the viewport size matches the configured width and height

Best Practices:

Use Cypress configuration file for settings

Use cy.viewport() to verify viewport size

Use cy.url() to assert current URL

Avoid hardcoding URLs in tests, use baseUrl config

Use beforeEach hook to set up test preconditions

Automated Solution

Cypress

/// <reference types="cypress" />

// cypress.config.js
const { defineConfig } = require('cypress')

module.exports = defineConfig({
  e2e: {
    baseUrl: 'https://example.com',
    defaultCommandTimeout: 10000,
    viewportWidth: 1280,
    viewportHeight: 720
  }
})

// cypress/e2e/configSettings.cy.js

describe('Cypress config settings test', () => {
  beforeEach(() => {
    cy.visit('/') // uses baseUrl from config
  })

  it('should have correct URL and viewport size', () => {
    cy.url().should('eq', 'https://example.com/')
    cy.viewport().then(viewport => {
      // viewport() does not return size, so use cy.window to check
      cy.window().then(win => {
        expect(win.innerWidth).to.equal(1280)
        expect(win.innerHeight).to.equal(720)
      })
    })
  })
})

The cypress.config.js file sets the baseUrl, defaultCommandTimeout, and viewport size. This centralizes configuration so tests do not hardcode these values.

The test visits the baseUrl by calling cy.visit('/'), which uses the configured baseUrl automatically.

We assert the URL is exactly the baseUrl with a trailing slash.

To verify viewport size, we check the window's innerWidth and innerHeight properties because cy.viewport() is a command to set viewport, not get it.

This approach follows best practices by using configuration, avoiding hardcoded URLs, and verifying settings through assertions.

Common Mistakes - 3 Pitfalls

Hardcoding full URLs in tests instead of using baseUrl config

Trying to get viewport size using cy.viewport() command

Not setting defaultCommandTimeout in config and relying on default

Bonus Challenge

Now add tests that verify the configuration works with three different baseUrls using environment variables

Show Hint

Practice

1. What is the main purpose of the cypress.config.js file in a Cypress project?

easy

A. To set configuration options like base URL and test locations for Cypress tests

B. To write the actual test cases for Cypress

C. To install Cypress dependencies

D. To run Cypress tests manually from the command line

Solution

1. Step 1: Understand the role of cypress.config.js

   This file is used to configure how Cypress runs tests, including settings like base URL and test file paths.

2. Step 2: Differentiate from other files

   Test cases are written in separate test files, not in the config file. Installation and running commands happen outside this file.

3. Final Answer:

   To set configuration options like base URL and test locations for Cypress tests -> Option A

4. Quick Check:

   Config file sets options = D [OK]

Hint: Config file sets test environment and paths [OK]

Common Mistakes:

• Confusing config file with test files
• Thinking config installs Cypress
• Believing config runs tests manually

2. Which of the following is the correct way to export the Cypress configuration using defineConfig in cypress.config.js?

easy

A. module.exports = { baseUrl: 'http://localhost:3000' }

B. export const config = { baseUrl: 'http://localhost:3000' }

C. defineConfig({ baseUrl: 'http://localhost:3000' })

D. export default defineConfig({ e2e: { baseUrl: 'http://localhost:3000' } })

Solution

1. Step 1: Recall the modern Cypress config syntax

   Since Cypress 10+, the config file uses defineConfig and exports it as default with ES module syntax.

2. Step 2: Check the correct structure

   The e2e object wraps settings like baseUrl. export default defineConfig({ e2e: { baseUrl: 'http://localhost:3000' } }) matches this pattern exactly.

3. Final Answer:

   export default defineConfig({ e2e: { baseUrl: 'http://localhost:3000' } }) -> Option D

4. Quick Check:

   Use defineConfig with export default = B [OK]

Hint: Use export default defineConfig({ e2e: { ... } }) [OK]

Common Mistakes:

• Forgetting to wrap settings inside e2e object
• Using CommonJS export instead of ES module
• Not using defineConfig function

3. Given this cypress.config.js snippet, what will be the base URL used during test runs?

import { defineConfig } from 'cypress'

export default defineConfig({
  e2e: {
    baseUrl: 'https://example.com',
    specPattern: 'cypress/e2e/**/*.cy.js'
  }
})

medium

A. http://localhost:3000

B. https://example.com

C. cypress/e2e/**/*.cy.js

D. No base URL is set

Solution

1. Step 1: Identify the baseUrl property in config

   The config sets baseUrl to 'https://example.com' inside the e2e object.

2. Step 2: Understand baseUrl usage

   This URL is used as the root for all relative URLs in tests, so it will be 'https://example.com'.

3. Final Answer:

   https://example.com -> Option B

4. Quick Check:

   baseUrl set to https://example.com = C [OK]

Hint: Look for baseUrl inside e2e object [OK]

Common Mistakes:

• Confusing specPattern with baseUrl
• Assuming default localhost URL
• Missing that baseUrl is inside e2e

4. You wrote this cypress.config.js but Cypress throws an error when running tests:

import { defineConfig } from 'cypress'

export default {
  e2e: {
    baseUrl: 'http://localhost:8080'
  }
}

What is the likely cause of the error?

medium

A. Using export default instead of module.exports

B. baseUrl must be outside the e2e object

C. Missing call to defineConfig wrapping the config object

D. baseUrl value must be an IP address

Solution

1. Step 1: Check the export syntax

   The config is exported as a plain object, but Cypress expects the config wrapped in defineConfig().

2. Step 2: Understand Cypress config requirements

   Without defineConfig, Cypress cannot properly parse the config, causing errors.

3. Final Answer:

   Missing call to defineConfig wrapping the config object -> Option C

4. Quick Check:

   Always wrap config in defineConfig() = A [OK]

Hint: Always wrap config object with defineConfig() [OK]

Common Mistakes:

• Placing baseUrl outside e2e
• Confusing export default with CommonJS
• Thinking baseUrl must be IP address

5. You want to set a custom environment variable API_KEY in cypress.config.js so it can be accessed in your tests. Which is the correct way to add it inside the config?

hard

A. export default defineConfig({ e2e: { env: { API_KEY: '12345' } } })

B. export default defineConfig({ env: { API_KEY: '12345' } })

C. export default defineConfig({ e2e: { baseUrl: 'http://localhost', API_KEY: '12345' } })

D. export default defineConfig({ e2e: { environment: { API_KEY: '12345' } } })

Solution

1. Step 1: Locate where environment variables go

   Environment variables for e2e tests go inside the env object nested within the e2e config.

2. Step 2: Verify correct property names

   The key must be env, not environment, and it must be inside e2e.

3. Final Answer:

   export default defineConfig({ e2e: { env: { API_KEY: '12345' } } }) -> Option A

4. Quick Check:

   Use e2e.env for env vars = A [OK]

Hint: Put env vars inside e2e.env object [OK]

Common Mistakes:

• Placing env outside e2e
• Using wrong key name like environment
• Adding env vars directly under e2e without env object