Cypress Fixture Not Loading in Intercept Fix

In this tutorial, you'll learn about Cypress Fixture Not Loading in Intercept Fix. We cover key concepts, practical examples, and best practices.

Your cy.fixture() data doesn't load into cy.intercept() — the fixture path is wrong or the data format doesn't match.

The Problem

// WRONG — fixture used as a value, not a function
cy.intercept('GET', '/api/users', cy.fixture('users'));
// cy.fixture() returns a Chainable, not the actual data

cy.fixture() returns a Cypress chainable, not the resolved fixture data. You can't use it directly as an intercept response.

Step-by-Step Fix

1. Use fixture in intercept with function

// RIGHT — fixture in intercept handler
cy.intercept('GET', '/api/users', { fixture: 'users.json' }).as('getUsers');

cy.visit('/users');
cy.wait('@getUsers');

2. Use fixture with before

// RIGHT — load fixture before intercept
let users;
before(() => {
  cy.fixture('users.json').then((data) => {
    users = data;
  });
});

beforeEach(() => {
  cy.intercept('GET', '/api/users', { body: users }).as('getUsers');
});

3. Conditional fixture loading

// RIGHT — different fixtures for different scenarios
cy.intercept('GET', '/api/users', (req) => {
  if (req.query.role === 'admin') {
    req.reply({ fixture: 'admin-users.json' });
  } else {
    req.reply({ fixture: 'users.json' });
  }
});

4. Modify fixture data before responding

// RIGHT — modify fixture dynamically
cy.fixture('user.json').then((user) => {
  user.name = 'Modified Name';
  cy.intercept('GET', '/api/user/1', { body: user }).as('getUser');
});

Expected output:

  ✓ intercept with fixture
  ✓ load fixture before intercept
  ✓ handle loading state with delayed response
  ✓ modify fixture dynamically

Prevention Tips

• Use { fixture: 'path.json' } in intercept options
• Load fixtures in before() for reusable test data
• Use .then() to access and modify fixture data
• Create separate fixtures for different scenarios
• Store fixtures in <a href="/testing-qa/cypress/">cypress</a>/fixtures/ directory

Common Mistakes with intercept fixture

1. Using foldl instead of foldl' causing stack overflow on large lists
2. Forgetting deriving (Show, Eq) on custom data types needed for debugging
3. Placing the wildcard pattern first in case expressions, making all subsequent patterns unreachable

These mistakes appear frequently in real-world CYPRESS code. DodaTech's contributors have identified these patterns through analysis of open-source projects and production systems.

Practice Exercise

Write a pure function that safely divides two integers using Maybe, then test it with edge cases like division by zero and negative numbers.

This exercise reinforces the concepts covered in this guide. Try implementing it before checking online solutions.

FAQ