Cypress Stuff

Autocomplete / Intellisense

For JavaScript

Add this to the top of each of your cypress test files:

javascript
/// <reference types="cypress" />

Check if you get any completions after typing cy.. If you don't see anything, try reloading your VSCode window.

For TypeScript

If you're using TypeScript, add the following to your tsconfig.json:

json
{
  "compilerOptions": {
    "types": ["cypress"]
  }
}

Testing with Material UI's <Select> Component

The snippets below test the following markup:

jsx
const Example = () => {
  return (
    <FormControl>
      <InputLabel id="number-select-label">Number</InputLabel>
      <Select
        data-testid="number-select"
        defaultValue=""
        label="Number"
        labelId="number-select-label"
        sx={{ width: '16rem' }}
      >
        <MenuItem value={10}>Ten</MenuItem>
        <MenuItem value={20}>Twenty</MenuItem>
        <MenuItem value={30}>Thirty</MenuItem>
      </Select>
    </FormControl>
  )
}

Plain Cypress

Warning

This method relies on adding a data-testid to the <Select>, and doesn't best reflect how an actual user would use it.

javascript
it('should work', () => {
  // Find the select using its `data-testid`
  cy.get('[data-testid="number-select"]')
    // alias the input for use later
    .as('number-select')
    // Click it
    .click()
 
  // Find the listbox that contains the options
  cy.get('[role="listbox"]')
    // Find the option with the value you want to click
    .get('[role="option"][data-value="20"]')
    // Click it
    .click()
 
  // Find the select by its alias
  cy.get('@number-select')
    // Check that value was selected correctly
    .contains(/twenty/i)
})

With @testing-library/cypress

Info

This method requires that the select have a label, where the id on the label equals the labelId prop on the Select. It's a bit more work, but it's probably what you'd want anyway (having a label for the <Select>) and makes your component more accessible.

javascript
it('should work', () => {
  // Find the select by its label
  cy.findByLabelText(/number/i)
    // alias the input for use later
    .as('number-select')
    // Click it
    .click()
 
  // Find the listbox that contains the options by its label text
  cy.findByLabelText(/number/i, { selector: '[role="listbox"]' })
    // Find the option with the value you want to click by the text that's shown
    .findByText(/twenty/i, { selector: '[role="option"]' })
    // Click it
    .click()
 
  // Get the select by its alias
  cy.get('@number-select')
    // Check that value was selected correctly
    .contains(/twenty/i)
})

Info

Remember to add import '@testing-library/cypress/add-commands' to cypress/support/commands.js. See more details here.

Run Commands

You can run any shell command using cy.exec. For example, if you want to run a command before each test, you can add the following adjacent to your individual test cases.

javascript
beforeEach(() => {
  cy.exec('echo "this is from cypress"')
  cy.visit('http://localhost:3000')
})
 
/** Your tests here */
Created 30/11/22 • Updated 12/01/23
Found a mistake, or want to suggest an improvement? Source on GitHub here
and see edit history here