Cypress installation (npm install cypress) - Framework Patterns

Framework Mode - Cypress installation (npm install cypress)

Folder Structure

my-cypress-project/
├── cypress/
│   ├── e2e/               # Test files (end-to-end tests)
│   │   └── example.cy.js  # Sample test file
│   ├── fixtures/          # Test data files (JSON, etc.)
│   ├── support/           # Custom commands and reusable code
│   │   ├── commands.js    # Custom Cypress commands
│   │   └── e2e.js         # Support file loaded before tests
├── cypress.config.js      # Cypress configuration file
├── node_modules/          # Installed npm packages
├── package.json           # Project metadata and dependencies
└── package-lock.json      # Exact versions of installed packages

Test Framework Layers

• Test Files (cypress/e2e): Contains your test scripts that describe user actions and assertions.
• Support Layer (cypress/support): Holds reusable commands and setup code to keep tests clean.
• Fixtures (cypress/fixtures): Stores static test data like JSON files for data-driven testing.
• Configuration (cypress.config.js): Defines environment settings, base URLs, and test options.
• Node Modules: Contains Cypress and other npm packages installed via npm install.

Configuration Patterns

Use cypress.config.js to manage settings like:

• Base URL: Define the main website URL to avoid repeating it in tests.
• Environment Variables: Store sensitive data like usernames or API keys securely using env property or .env files.
• Test Files Pattern: Specify which files Cypress should consider as tests.

Example snippet from cypress.config.js:

import { defineConfig } from 'cypress'

export default defineConfig({
  e2e: {
    baseUrl: 'https://example.com',
    env: {
      username: 'testuser',
      password: 'securePass123'
    },
    specPattern: 'cypress/e2e/**/*.cy.js'
  }
})

Test Reporting and CI/CD Integration

• Built-in Cypress Reporter: Shows test results in the terminal and interactive GUI.
• Third-party Reporters: Integrate with tools like Mochawesome for detailed HTML reports.
• CI/CD Integration: Run Cypress tests automatically on platforms like GitHub Actions, GitLab CI, or Jenkins using npx cypress run.
• Artifacts: Save screenshots and videos on test failures for debugging.

Best Practices

• Use npm to install Cypress: Run npm install cypress --save-dev to add Cypress as a development dependency.
• Keep tests isolated: Each test should be independent to avoid flaky results.
• Use support files: Put reusable commands and setup code in cypress/support to keep tests clean.
• Manage sensitive data securely: Use environment variables instead of hardcoding credentials.
• Run tests in CI/CD: Automate test runs on code changes to catch issues early.

Self Check

Where in this folder structure would you add a new test file for verifying the login functionality?

Answer: Add the new test file inside the cypress/e2e/ folder, for example cypress/e2e/login.cy.js.

Key Result

Cypress test framework organizes tests in cypress/e2e, reusable code in support, and config in cypress.config.js, installed via npm.

Practice

1. What is the correct command to install Cypress as a development dependency using npm?

easy

A. npm install cypress --global

B. npm install cypress --save-dev

C. npm install cypress --save

D. npm install cypress --production

Solution

1. Step 1: Understand npm install flags

   The --save-dev flag installs the package as a development dependency, which is correct for Cypress.

2. Step 2: Compare options

   Options A, C, and D use incorrect flags for Cypress installation as a dev dependency.

3. Final Answer:

   npm install cypress --save-dev -> Option B

4. Quick Check:

   Install Cypress as dev dependency = npm install cypress --save-dev [OK]

Hint: Use --save-dev to install testing tools like Cypress [OK]

Common Mistakes:

• Using --global installs globally, not per project
• Using --save installs as production dependency
• Omitting --save-dev installs but not saved in devDependencies

2. Which folder should you be in before running npm install cypress --save-dev?

easy

A. The folder containing your package.json

B. The global npm modules folder

C. Any folder on your computer

D. The Cypress installation folder

Solution

1. Step 1: Identify project root folder

   npm installs packages into the current project, so you must be in the folder with package.json.

2. Step 2: Eliminate other options

   Installing anywhere else won't link Cypress to your project correctly.

3. Final Answer:

   The folder containing your package.json -> Option A

4. Quick Check:

   Install inside project folder with package.json [OK]

Hint: Always run npm install where package.json lives [OK]

Common Mistakes:

• Running npm install in random folders
• Trying to install inside global npm folder
• Assuming Cypress folder exists before install

3. After running npm install cypress --save-dev, what command do you use to open the Cypress Test Runner?

medium

A. npx cypress open

B. cypress start

C. npm run cypress

D. npm start cypress

Solution

1. Step 1: Recall Cypress start command

   The correct command to open Cypress Test Runner is npx cypress open.

2. Step 2: Check other options

   Options A, B, and C are not valid commands to open Cypress.

3. Final Answer:

   npx cypress open -> Option A

4. Quick Check:

   Open Cypress with npx cypress open [OK]

Hint: Use npx to run Cypress without global install [OK]

Common Mistakes:

• Trying npm start or npm run without scripts
• Typing cypress start instead of npx cypress open
• Not using npx after local install

4. You ran npm install cypress --save-dev but get an error saying command not found: cypress when typing cypress open. What is the likely fix?

medium

A. Restart your computer

B. Reinstall Cypress globally with npm install -g cypress

C. Delete node_modules and reinstall

D. Run npx cypress open instead

Solution

1. Step 1: Understand local vs global commands

   Cypress installed locally is not available as a global command, so cypress open fails.

2. Step 2: Use npx to run local binaries

   Using npx cypress open runs the local Cypress binary correctly.

3. Final Answer:

   Run npx cypress open instead -> Option D

4. Quick Check:

   Use npx for local binaries to avoid command not found [OK]

Hint: Use npx to run local packages without global install [OK]

Common Mistakes:

• Trying to run cypress without npx after local install
• Installing Cypress globally unnecessarily
• Ignoring error and assuming install failed

5. You want to add Cypress to your project and ensure it is only used during development. Which sequence of commands correctly installs Cypress and opens the test runner?

hard

A. npm install cypress --global && npx cypress open

B. npm install cypress && cypress open

C. npm install cypress --save-dev && npx cypress open

D. npm install cypress --save && npm start cypress

Solution

1. Step 1: Install Cypress as a development dependency

   Use npm install cypress --save-dev to add Cypress only for development.

2. Step 2: Open Cypress Test Runner correctly

   Use npx cypress open to run Cypress without global install.

3. Final Answer:

   npm install cypress --save-dev && npx cypress open -> Option C

4. Quick Check:

   Dev install + npx open = correct Cypress setup [OK]

Hint: Install with --save-dev then open with npx cypress open [OK]

Common Mistakes:

• Installing Cypress globally when not needed
• Running cypress open without npx after local install
• Using npm start without proper scripts