cypress-time

Record timings in Cypress

Why?

Sometimes you want to record how long a series of tasks/actions take. When developing, you might use browser-based time spans to give you feedback. This Cypress plugin will give you a nice way to do timings right in your test! This library uses the User Timings API, so the time span will show up if you run a performance profile while the test is active (can only be done using cypress open which is dev mode).

Installation

To install the module:

npm install cypress-time --save-dev

To get the plugin working with Cypress:

// cypress/support/index.js or cypress/support/index.ts
import 'cypress-time'

Use

In your spec files, cy.time(label) will start a time span while cy.timeEnd(label) will end a time span. cy.timeEnd will return a PerformanceEntry.

// start the 'test' time span
cy.time('test')

cy.contains('button', 'Submit').click()

// wait until submit is complete - assume a backend is involved
cy.get('Loading').should('not.exist')

// ends the 'test' time span, printing the duration
cy.timeEnd('test')

If you want to do something with the time output, the PerformanceEntry is returned. You can save this to a file, send it off to a service, or whatever you'd like. startTime and duration may be of the most interest.

cy.time('test')

// do something

cy.timeEnd('test').then(entry => {
  console.log(entry.startTime) // start in ms elapsed since page loaded
  console.log(entry.duration) // duration between `time` and `timeEnd`
})

Here's a screenshot of what the command log will look like:

Here's a screenshot of the Performance tools with the 'test' time span:

Typescript support

This plugin comes with its own type definitions. If you're using Typescript already and your support index file is a Typescript file and your tsconfig.json is configured to include *.ts files in the support directory, nothing more needs to be done. If you don't have your project set up this way, add the following to your tsconfig (ideally in cypress/tsconfig.json):

{
  "types": ["cypress", "cypress-time"]
}