aaronrmiller / expect-playwright

Jest utility matcher functions to simplify expect statements for the usage with Playwright.

expect-playwright

This library provides utility matchers for Jest in combination with Playwright. All of them are exposed on the expect object. You can use them either directly or invert them via the .not property like shown in a example below.

npm install -D expect-playwright playwright-core

Usage

With Jest

To activate it in your Jest environment you have to include it in your configuration.

{
    "setupFilesAfterEnv": ["expect-playwright"]
}

Without Jest

import expect from "expect-playwright"

await expect(page).toHaveText("#foo", "my text")

Why do I need it

The Playwright API is great, but it is low level and not designed for integration testing. So this package tries to provide a bunch of utility functions to perform the common checks easier.

Example which should wait and compare the text content of a paragraph on the page.

// before
await page.waitForSelector("#foo")
const textContent = await page.$eval("#foo", el => el.textContent)
expect(textContent).stringContaining("my text")

// after by using expect-playwright
await expect(page).toHaveText("#foo", "my text")

API documentation

Table of Contents

• toHaveSelector
• toHaveText
• toEqualText
• toEqualValue

toHaveSelector

expect(page: Page).toHaveSelector(selector: string, options?: PageWaitForSelectorOptions)

This function waits as a maximum as the timeout exceeds for a given selector once it appears on the page.

await expect(page).toHaveSelector("#foobar")
// or via not, useful to only wait 1 second instead of for the default timeout by Playwright which is 30 seconds.
await expect(page).not.toHaveSelector("#foobar", {
  timeout: 1 * 1000
})

toHaveText

This function checks if the the textContent of a given element contains the provided value.

You can do this via a selector on the whole page:

expect(page: Page).toHaveText(selector: string, value: string, options?: PageWaitForSelectorOptions)

await expect(page).toHaveText("#my-element", "MyValue")

Or without a selector which will use the body element:

expect(page: Page).toHaveText(value: string)

await expect(page).toHaveText("Playwright")

Or by passing a Playwright ElementHandle:

expect(page: ElementHandle).toHaveText(value: string)

const element = await page.$('#my-element');
await expect(element).toHaveText("Playwright")

By default it waits 1 second for the element which you can overwrite via the options.

toEqualText

This function checks if the textContent of a given element is the same as the provided value.

You can do this via a selector on the whole page:

expect(page: Page).toEqualText(selector: string, value: string, options?: PageWaitForSelectorOptions)

await expect(page).toEqualText("#my-element", "Playwright")

Or without a selector which will use the body element:

expect(page: Page).toEqualText(value: string, options?: PageWaitForSelectorOptions)

await expect(page).toEqualText("Playwright")

Or by passing a Playwright ElementHandle:

expect(page: ElementHandle).toEqualText(value: string, options?: PageWaitForSelectorOptions)

const element = await page.$('#my-element');
await expect(element).toEqualText("Playwright")

By default it waits 1 second for the element which you can overwrite via the options.

toEqualValue

This function checks if the value of a given element is the same as the provided value.

You can do this via a selector or the element directly:

expect(page: Page).toEqualValue(selector: string, value: string, options?: PageWaitForSelectorOptions)

await expect(page).toEqualValue("#my-element", "Playwright")

Or by passing a Playwright ElementHandle:

expect(page: ElementHandle).toEqualValue(value: string, options?: PageWaitForSelectorOptions)

const element = await page.$('#my-element');
await expect(element).toEqualValue("Playwright")

By default it waits 1 second for the element which you can overwrite via the options.

Examples

import playwright from 'playwright-chromium'

describe("GitHub Playwright project", () => {
  it("should should have Playwright in the README heading", async () => {
    const browser = await playwright.chromium.launch()
    const page = await browser.newPage()
    await page.goto("https://github.com/microsoft/playwright")
    await expect(page).toHaveText("#readme h1", "Playwright")
    // or also all of them via the not property
    await expect(page).not.toHaveText("this-is-no-anywhere", { timeout: 1 * 1000 })
    await browser.close()
  })
})

TypeScript

There are typings available. For that just import

import "expect-playwright"

at the top of your test file or include it globally in your tsconfig.json.

Inspired by

• expect-puppeteer