cypress/docs/source/api/utilities/promise.md

title: cypress-promise comments: true

new Cypress.Promise( function )

Cypress automatically proxies Bluebird and exposes it as Cypress.Promise.

Instantiate a new bluebird promise.

---

Usage

Use Cypress.Promise to create promises. Cypress is promise aware so if you return a promise from inside of commands like cy.then, Cypress will not continue until those promises resolve.

Basic Promise

cy.get("button").then(function($button){
  return new Cypress.Promise(function(resolve, reject){
    // do something custom here
  })
})

---

Waiting for Promises

it("waits for promises to resolve", function(){
  var waited = false

  function waitOneSecond(){
    // return a promise that resolves after 1 second
    return new Cypress.Promise(function(resolve, reject){
      setTimeout(function(){
        // set waited to true
        waited = true

        // resolve with 'foo' string
        resolve('foo')
      }, 1000)
    })
  }

  cy
    .then(function(){
      // return a promise to cy.then() that
      // is awaited until it resolves
      return waitOneSecond().then(function(str){
        expect(str).to.eq('foo')
        expect(waited).to.be.true
      })
    })
})