cypress-expect-n-assertions

Cypress helper that checks number of expected and actual assertions in the test

Example

const {plan} = require('cypress-expect-n-assertions')
it('has 2 expects', () => {
  plan(2)
  expect(1, 'one').to.equal(1)
  expect(2, 'two').to.equal(2)
})

If the test for some reason runs a different number of assertions, the test will fail using afterEach hook. Same test, but with a wrong plan argument generates a failure

const {plan} = require('cypress-expect-n-assertions')
it('has 2 expects', () => {
  plan(1) // wrong value on purpose
  expect(1, 'one').to.equal(1)
  expect(2, 'two').to.equal(2)
})

The afterEach hook used in this module will automatically wait if the number of assertions is below the plan. For example, the following test executes the second assertion asynchronously after 2 second delay

it('has async assertion, will wait automatically', () => {
  plan(2)
  expect(1, 'one').to.equal(1)
  setTimeout(() => {
    expect(2, 'two').to.equal(2)
  }, 2000)
})

The video below shows how the test automatically waits (up to defaultCommandTimeout) for the "missing" assertion to happen.

Limitations

To avoid multiple mocking of expect, for now you can only run individual spec files. Do not use "Run all specs" button.

Small print

Author: Gleb Bahmutov © 2020

• @bahmutov
• glebbahmutov.com
• blog
• videos
• presentations
• cypress.tips
• Cypress Tips & Tricks Newsletter
• my Cypress courses

License: MIT - do anything with the code, but don't blame me if it does not work.

Spread the word: tweet, star on github, etc.

Support: if you find any problems with this module, email / tweet / open an issue on Github

MIT License

Copyright (c) 2020 Gleb Bahmutov

Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.