How to test requests are resolved in a specific order

Question

I'm trying to write a Cypress test that validates that a specific request is resolved before another. Here is my code:

it('Module 1 should load before Module 2', () => {
  // Delay Module 1 by 5 seconds
  cy.intercept('module1.js', (req) => {
    req.on('response', (res) => {
      res.setThrottle(5000);
    });
  }).as('module1');
  cy.intercept('module2.js').as('module2');

  cy.visit('/');

  // Module 1 should load before Module 2 even though it's delayed
  cy.wait('@module1');
  cy.wait('@module2');
});

This test is predicated on cy.wait()s resolving in order, but that does not appear to be the case. If I switch the two cy.wait()s to the following, the test still passes.

cy.wait('@module2');
cy.wait('@module1');

I've even tried having the second wait occur in the then() block of the first, but it still doesn't seem to care about order.

cy.wait('@module2').then(() => {
  cy.wait('@module1');
});

How can I test that two requests are resolved in a specific order?

Answer 1

Perhaps timestamp the responses and wait for them together

it('Module 1 should load before Module 2', () => {
  // Delay Module 1 by 5 seconds
  cy.intercept('module1.js', (req) => {
    req.on('response', (res) => {
      res.setThrottle(5000);
      res.timestamp = Date.now()
    });
  }).as('module1');
  cy.intercept('module2.js', (req) => {
    req.on('response', (res) => {
      res.timestamp = Date.now()
    });
  }).as('module2');

  cy.visit('/');

  // Module 1 should load before Module 2 even though it's delayed
  cy.wait(['@module1', '@module2').then(interceptions => {
    expect(interceptions[0].timestamp).to.be.lt(interceptions[1].timestamp)
  })
});