Implementation:Cypress io Cypress React Mount

Knowledge Sources	Cypress React Component Testing
Domains	Component_Testing, React
Last Updated	2026-02-12 00:00 GMT

Overview

Concrete tool for mounting React components in Cypress component tests provided by the cypress/react package.

Description

The mount function from cypress/react renders a React component into the Cypress DOM container using ReactDOM.createRoot. It cleans up any previously mounted component, creates a root if needed, renders the JSX, and returns a Cypress.Chainable<MountReturn> for chaining assertions. It delegates to makeMountFn which handles logging, container element management, and the Cypress command integration.

Usage

Import this function in component test files or in cypress/support/component.ts to register it as a custom cy.mount command.

Code Reference

Source Location

• Repository: cypress-io/cypress
• File: npm/react/src/mount.ts
• Lines: L47-66

Signature

export function mount(
  jsx: React.ReactNode,
  options: MountOptions = {},
  rerenderKey?: string
): Cypress.Chainable<MountReturn>

Import

import { mount } from 'cypress/react'

I/O Contract

Inputs

Name	Type	Required	Description
jsx	React.ReactNode	Yes	React JSX element to mount
options	MountOptions	No	Mount options (strict mode, ReactDom override, etc.)
rerenderKey	string	No	Key to force re-render of the same component

Outputs

Name	Type	Description
Chainable<MountReturn>	Cypress.Chainable	Chainable wrapping the mounted component for assertions

Usage Examples

Basic React Component Test

import { mount } from 'cypress/react'
import { Button } from './Button'

describe('Button', () => {
  it('renders with label', () => {
    mount(<Button label="Click me" />)
    cy.get('button').should('have.text', 'Click me')
  })

  it('handles click', () => {
    const onClick = cy.stub()
    mount(<Button label="Click" onClick={onClick} />)
    cy.get('button').click()
    cy.wrap(onClick).should('have.been.calledOnce')
  })
})

Related Pages

Implements Principle

• Principle:Cypress_io_Cypress_Component_Mounting