Fixtures and Test Data

Where test data comes from

Files in cypress/fixtures (often JSON) hold static data: load them with cy.fixture('user.json') or reference them in cy.intercept(..., { fixture: 'todos.json' }). For dynamic data, generate unique values per test (for example an email with a timestamp) so tests never collide. To create or reset data in the backend, call an API with cy.request or run Node code with cy.task, registered in setupNodeEvents in the config, which can talk to a database or seed script. Cypress.env() reads environment-specific values such as credentials; keep secrets out of committed config files.

Fixtures, a seed task and unique data

Config and spec.

// cypress.config.ts
import { defineConfig } from 'cypress';
import { resetDb, seedUser } from './scripts/db';

export default defineConfig({
  e2e: {
    baseUrl: 'http://localhost:3000',
    setupNodeEvents(on) {
      on('task', {
        'db:reset': () => resetDb().then(() => null),
        'db:seedUser': (email: string) => seedUser(email),
      });
    },
  },
});

// cypress/e2e/profile.cy.ts
describe('profile', () => {
  beforeEach(() => {
    cy.task('db:reset');
  });

  it('shows the seeded user', () => {
    const email = `user-${Date.now()}@example.com`;
    cy.task('db:seedUser', email);
    cy.fixture('profile.json').then((profile) => {
      cy.intercept('GET', '/api/profile', { ...profile, email });
    });
    cy.visit('/profile');
    cy.contains(email).should('be.visible');
  });
});

Tasks must return a value

A cy.task handler must return a value or a promise; return null rather than undefined when there is nothing useful to send back, or Cypress reports an error.

त्वरित जाँच: Where does code registered with on('task', ...) run?

• In the Node.js process, so it can reach databases and the file system
• Inside the application under test
• In the browser console only
• On the Cypress Cloud servers