and

Create an assertion. Assertions are automatically retried as part of the previous command until they pass or time out.

Syntax

.and(chainers)
.and(chainers, value)
.and(chainers, method, value)
.and(callbackFn)

Usage

Correct Usage

cy.get('.err').should('be.empty').and('be.hidden') // Assert '.err' is empty & hidden

cy.contains('Login').and('be.visible') // Assert el is visible

cy.wrap({ foo: 'bar' })
  .should('have.property', 'foo') // Assert 'foo' property exists
  .and('eq', 'bar') // Assert 'foo' property is 'bar'

Incorrect Usage

cy.and('eq', '42') // Can not be chained off 'cy'

cy.get('button').click().and('be.focused') // Should not be chained off
// action commands that may update the DOM

Arguments

chainers (String)

Any valid chainer that comes from Chai or Chai-jQuery or Sinon-Chai.

value (String)

Value to assert against chainer.

method (String)

A method to be called on the chainer.

callbackFn (Function)

Pass a function that can have any number of explicit assertions within it. Whatever was passed to the function is what is yielded.

Yields

  • In most cases, .and() yields the same subject it was given.
  • .and() is an assertion, and it is safe to chain further commands that use the subject.
cy.get('nav') // yields <nav>
  .should('be.visible') // yields <nav>
  .and('have.class', 'open') // yields <nav>

However, some chainers change the subject. In the example below, .and() yields the string sans-serif because the chainer have.css, 'font-family' changes the subject.

cy.get('nav') // yields <nav>
  .should('be.visible') // yields <nav>
  .and('have.css', 'font-family') // yields 'sans-serif'
  .and('match', /serif/) // yields 'sans-serif'

Examples

Chainers

Chain assertions on the same subject

cy.get('button').should('have.class', 'active').and('not.be.disabled')

Value

Chain assertions when yield changes

<!-- App Code -->
<ul>
  <li>
    <a href="users/123/edit">Edit User</a>
  </li>
</ul>
cy.get('a')
  .should('contain', 'Edit User') // yields <a>
  .and('have.attr', 'href') // yields string value of href
  .and('match', /users/) // yields string value of href
  .and('not.include', '#') // yields string value of href

Method and Value

Assert the href is equal to '/users'

cy.get('#header a')
  .should('have.class', 'active')
  .and('have.attr', 'href', '/users')

Function

Verify length, content, and classes from multiple <p>

Passing a function to .and() enables you to assert on the yielded subject. This gives you the opportunity to massage what you'd like to assert.

Be sure not to include any code that has side effects in your callback function.

The callback function will be retried over and over again until no assertions within it throw.

<div>
  <p class="text-primary">Hello World</p>
  <p class="text-danger">You have an error</p>
  <p class="text-default">Try again later</p>
</div>
cy.get('p')
  .should('not.be.empty')
  .and(($p) => {
    // should have found 3 elements
    expect($p).to.have.length(3)

    // make sure the first contains some text content
    expect($p.first()).to.contain('Hello World')

    // use jquery's map to grab all of their classes
    // jquery's map returns a new jquery object
    const classes = $p.map((i, el) => {
      return Cypress.$(el).attr('class')
    })

    // call classes.get() to make this a plain array
    expect(classes.get()).to.deep.eq([
      'text-primary',
      'text-danger',
      'text-default',
    ])
  })

Notes

Chai

Similarities to Chai

If you've worked in Chai before, you will recognize that .and() matches the same fluent assertion syntax.

Take this explicit assertion for example:

expect({ foo: 'bar' }).to.have.property('foo').and.eq('bar')

.and() reproduces this same assertion behavior.

Subjects

How do I know which assertions change the subject and which keep it the same?

The chainers that come from Chai or Chai-jQuery will always document what they return.

Using a callback function will not change what is yielded

Whenever you use a callback function, its return value is always ignored. Cypress always forces the command to yield the value from the previous cy command's yield (which in the example below is <button>)

cy.get('button')
  .should('be.active')
  .and(($button) => {
    expect({ foo: 'bar' }).to.deep.eq({ foo: 'bar' })

    return { foo: 'bar' } // return is ignored, .and() yields <button>
  })
  .then(($button) => {
    // do anything we want with <button>
  })

Differences

What's the difference between .then() and .should()/.and()?

Using .then() allows you to use the yielded subject in a callback function and should be used when you need to manipulate some values or do some actions.

When using a callback function with .should() or .and(), on the other hand, there is special logic to rerun the callback function until no assertions throw within it. You should be careful of side affects in a .should() or .and() callback function that you would not want performed multiple times.

Rules

Requirements

  • .and() requires being chained off a previous command.

Timeouts

  • .and() will continue to retry its specified assertions until it times out.
cy.get('input', {timeout: 10000}).should('have.value', '10').and('have.class', 'error')// timeout here will be passed down to the '.and()'
  // and it will retry for up to 10 secs
cy.get('input', {timeout: 10000}).should('have.value', 'US').and(($input) => {// timeout here will be passed down to the '.and()'
  // unless an assertion throws earlier,
  // ALL of the assertions will retry for up to 10 secs
  expect($input).to.not.be('disabled')
  expect($input).to.not.have.class('error')
})

Command Log

Chain assertions on the same subject

cy.get('.list')
  .find('input[type="checkbox"]')
  .should('be.checked')
  .and('not.be.disabled')

The commands above will display in the Command Log as:

Command log for assertions

When clicking on assert within the command log, the console outputs the following:

console.log for assertions

See also