expect-webdriverio

API | TypeScript / JS Autocomplete | Examples | Extending Matchers

WebdriverIO assertion library inspired by expect

Key Features

• Waits for expectations to succeed
• Supports single element $() & multiple elements $$()
• Detailed error messages
• Works in Mocha, Cucumber, Jest, and Jasmine
• Built-in types for TypeScript and JS autocompletion

Installation

1. npm install expect-webdriverio
2. Install your test framework adapter (if not already set up via WDIO testrunner):
   • Mocha (default): npm install @wdio/mocha-framework
   • Jasmine: npm install @wdio/jasmine-framework
   • Cucumber: npm install @wdio/cucumber-framework
   • Jest: No adapter needed — see Jest Framework section

Note: WebdriverIO v9.0.0 or higher is required!

Usage

Using WebdriverIO Testrunner

If you run your tests through the WDIO testrunner, no additional setup is needed. WebdriverIO initializes expect-webdriverio and makes expect available in the global scope so you can use it directly in your tests:

await expect($('button')).toBeDisplayed()
await expect($$('buttons')).toBeDisplayed()

See more Examples.

Local & Browser Runners

• Local Runner: Fully compatible. You can leverage your test framework adapter as mentioned above.
• Browser Runner: Designed for component frameworks like React, Preact, Vue.js, Svelte, and SolidJS, with a few known limitations. For details, see the Browser Runner Framework section.

Using in Standalone Mode

If you use WebdriverIO in standalone mode (without @wdio/globals), make sure you import expect-webdriverio before using it anywhere.

import { remote } from 'webdriverio'
import { expect } from 'expect-webdriverio'

;(async () => {
    const browser = await remote({
        capabilities: {
            browserName: 'chrome'
        }
    })

    await browser.url('https://webdriver.io')

    const $button = await browser.$('button')
    await expect($button).toBeDisplayed()
    
    await browser.deleteSession()
})().catch(console.error)

API

Please see the API documentation.

Error Messages

Error messages are informative out of the box and contain:

• Full element selector, like $('form')
• Actual and expected values
• Highlighted differences (text assertions)

What's Next?

First of all, feel free to raise an issue with your suggestions or help with PRs!

Planned

• Cookie matchers
• Multiremote support (in progress)