playwright/docs/src/test-pom-js.md
2021-08-23 20:10:12 -07:00

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---
id: test-pom
title: "Page Object Model"
---
Page Object Model is a common pattern that introduces abstractions over web app pages to simplify interactions with them in multiple tests. It is best explained by an example.
We will create a `PlaywrightDevPage` helper class to encapsulate common operations on the `playwright.dev` page. Internally, it will use the `page` object.
```js js-flavor=js
// playwright-dev-page.js
const { expect } = require('@playwright/test');
exports.PlaywrightDevPage = class PlaywrightDevPage {
/**
* @param {import('@playwright/test').Page} page
*/
constructor(page) {
this.page = page;
this.getStartedLink = page.locator('text=Get started');
this.coreConceptsLink = page.locator('text=Core concepts');
this.tocList = page.locator('article ul > li > a');
}
async goto() {
await this.page.goto('https://playwright.dev');
}
async getStarted() {
await this.getStartedLink.first().click();
await expect(this.coreConceptsLink).toBeVisible();
}
async coreConcepts() {
await this.getStarted();
await this.page.click('text=Guides');
await this.coreConceptsLink.click();
await expect(this.page.locator('h1').locator("text=Core concepts")).toBeVisible();
}
}
```
```js js-flavor=ts
// playwright-dev-page.ts
import { expect, Locator, Page } from '@playwright/test';
export class PlaywrightDevPage {
readonly page: Page;
readonly getStartedLink: Locator;
readonly coreConceptsLink: Locator;
readonly tocList: Locator;
constructor(page: Page) {
this.page = page;
this.getStartedLink = page.locator('text=Get started');
this.coreConceptsLink = page.locator('text=Core concepts');
this.tocList = page.locator('article ul > li > a');
}
async goto() {
await this.page.goto('https://playwright.dev');
}
async getStarted() {
await this.getStartedLink.first().click();
await expect(this.coreConceptsLink).toBeVisible();
}
async coreConcepts() {
await this.getStarted();
await this.page.click('text=Guides');
await this.coreConceptsLink.click();
await expect(this.page.locator('h1').locator("text=Core concepts")).toBeVisible();
}
}
```
Now we can use the `PlaywrightDevPage` class in our tests.
```js js-flavor=js
// example.spec.js
const { test, expect } = require('@playwright/test');
const { PlaywrightDevPage } = require('./playwright-dev-page');
test('Get Started table of contents', async ({ page }) => {
const playwrightDev = new PlaywrightDevPage(page);
await playwrightDev.goto();
await playwrightDev.getStarted();
await expect(playwrightDev.tocList).toHaveText([
'Installation',
'First test',
'Writing assertions',
'Using test fixtures',
'Using test hooks',
'Learning the command line',
'Creating a configuration file',
'Release notes',
]);
});
test('Core Concepts table of contents', async ({ page }) => {
const playwrightDev = new PlaywrightDevPage(page);
await playwrightDev.goto();
await playwrightDev.coreConcepts();
await expect(playwrightDev.tocList.first()).toHaveText('Browser');
});
```
```js js-flavor=ts
// example.spec.ts
import { test, expect } from '@playwright/test';
import { PlaywrightDevPage } from './playwright-dev-page';
test('Get Started table of contents', async ({ page }) => {
const playwrightDev = new PlaywrightDevPage(page);
await playwrightDev.goto();
await playwrightDev.getStarted();
await expect(playwrightDev.tocList).toHaveText([
'Installation',
'First test',
'Writing assertions',
'Using test fixtures',
'Using test hooks',
'Learning the command line',
'Creating a configuration file',
'Release notes',
]);
});
test('Core Concepts table of contents', async ({ page }) => {
const playwrightDev = new PlaywrightDevPage(page);
await playwrightDev.goto();
await playwrightDev.coreConcepts();
await expect(playwrightDev.tocList.first()).toHaveText('Browser');
});
```