playwright/docs/src/test-parameterize-js.md

id	title
test-parameterize	Parameterize tests

You can either parameterize tests on a test level or on a project level.

Parametrized Tests

// example.spec.js
const people = ['Alice', 'Bob'];
for (const name in people) {
  test(`testing with ${name}`, async () => {
    // ...
  });
  // You can also do it with test.describe() or with multiple tests as long the test name is unique.
}

// example.spec.ts
const people = ['Alice', 'Bob'];
for (const name in people) {
  test(`testing with ${name}`, async () => {
    // ...
  });
  // You can also do it with test.describe() or with multiple tests as long the test name is unique.
}

Parametrized Projects

Playwright Test supports running multiple test projects at the same time. In the following example, we'll run two projects with different parameters. A parameter itself is represented as a fixture, where the value gets set from the config. The first project runs with the value Alice and the second with the value Bob.

// my-test.js
const base = require('@playwright/test');

exports.test = base.test.extend({
  // Default value for person.
  person: 'not-set',
});

// my-test.ts
import { test as base } from '@playwright/test';

export type TestOptions = {
  person: string;
};

export const test = base.extend<TestOptions>({
  // Default value for the person.
  person: 'not-set',
});

We can use our fixtures in the test.

// example.spec.js
const { test } = require('./my-test');

test('test 1', async ({ page, person }) => {
  await page.goto(`/index.html`);
  await expect(page.locator('#node')).toContainText(person);
  // ...
});

// example.spec.ts
import { test } from './my-test';

test('test 1', async ({ page, person }) => {
  await page.goto(`/index.html`);
  await expect(page.locator('#node')).toContainText(person);
  // ...
});

Now, we can run test in multiple configurations by using projects.

// playwright.config.js
// @ts-check

/** @type {import('@playwright/test').PlaywrightTestConfig<{ version: string }>} */
const config = {
  projects: [
    {
      name: 'Alice',
      use: { person: 'Alice' },
    },
    {
      name: 'Bob',
      use: { person: 'Bob' },
    },
  ]
};

module.exports = config;

// playwright.config.ts
import { PlaywrightTestConfig } from '@playwright/test';
import { TestOptions } from './my-test';

const config: PlaywrightTestConfig<TestOptions> = {
  timeout: 20000,
  projects: [
    {
      name: 'alice',
      use: { person: 'Alice' },
    },
    {
      name: 'Bob',
      use: { person: 'Bob' },
    },
  ]
};
export default config;