Cannot find element in JSON body

[FransPeterson]

I noticed that a certain assertion was failing when upgrading from version 3.8.3 towards 4.1.0. I downgraded the version back towards 3.8.3 and it's passing again.

Current behavior:

Desired behavior:

Assertion should pass.

Test code to reproduce

describe('API Testing with Cypress', () => {

  var baseURL = "https://pokeapi.co/api/v2/pokemon"

  beforeEach(() => {
      cy.request(baseURL+"/25").as('pikachu');
  });

  it('Print response body',() => {
    cy.get('@pikachu')
    .its('body')
    .then((apivalue) => {
          cy.log(apivalue)
        })
  });

  it('Validate the header', () => {
      cy.get('@pikachu')
          .its('headers')
          .its('content-type')
          .should('include', 'application/json; charset=utf-8');
  });

  it('Validate the status code', () => {
      cy.get('@pikachu')
          .its('status')
          .should('equal', 200);
  });

  it("Validate the pokemon's name", () => {
    cy.get("@pikachu") 
      .its('body')
      .its('forms')
      .should('include', { 
        name: 'pikachu', 
        url: 'https://pokeapi.co/api/v2/pokemon-form/25/' 
      })
      .should('not.include', {
        name: 'johndoe'
      });
  })

Versions

Working in 3.8.3
Not working in 4.1.0

[jennifer-shehane]

I can confirm this change in behavior starting in 4.0.0.

This expected behavior and is due to our upgrade of Chai from 3.5.0 to 4.2.0 which included breaking changes. Specifically:

Previously, .include was using strict equality (===) for non-negated property inclusion, but deep equality for negated property inclusion and array inclusion.

This upgrade causes include to always use strict equality unless the deep property is set.

There's a bit of a deeper explanation here, but essentially in 3.x, a different equality check was being applied for not.include versus include, which is now fixed

3.8.3

4.0.0

To fix:

Update your assertion to use deep.include for deep equality and include for strict equality. The below code passes in 4.0.0, for example.

it("Validate the pokemon's name", () => {
  cy.request('https://pokeapi.co/api/v2/pokemon/25').as('pikachu');
  cy.get("@pikachu")
    .its('body')
    .its('forms')
    .should('deep.include', {
      name: 'pikachu',
      url: 'https://pokeapi.co/api/v2/pokemon-form/25/'
    })
})

[jennifer-shehane]

I've opened a PR in our docs to more specifically note this in our Migration Guide cypress-io/cypress-documentation#2574

[FransPeterson]

Thanks for the information.