Microsoft Playwright Testing Interview Questions & Answers

obj?.a?.b safely reads nested properties and returns undefined instead of throwing if something in the chain is missing.

Use device descriptors such as devices['iPhone 13'] in a project config to emulate viewport, user agent and touch.

Before acting, Playwright waits for the element to be attached, visible, stable, enabled and able to receive events — so manual waits are rarely needed.

Define an interface for the payload, cast or validate the parsed JSON to it (for example with zod), and use that type in assertions to catch shape changes.

Install the allure-playwright reporter, add it in the config reporters array and generate the report from the allure-results folder in CI.

A type alias describes a shape or union of values; an enum creates a named set of constants that exists at runtime.

Integrate axe-core through @axe-core/playwright, run an analysis on the page and assert that there are no violations.

Define projects for chromium, firefox and webkit in playwright.config.ts, set workers, then run: npx playwright test

test('login', async ({ page }) => { await page.goto('/login'); await page.getByLabel('Email').fill('a@b.com'); await page.getByLabel('Password').fill('secret'); await page.getByRole('button', { name: 'Login' }).click(); await expect(page.getByRole('heading', { name: 'Dashboard' })).toBeVisible(); });

string, number, boolean, null, undefined, symbol, bigint and object (including arrays and functions).

Add retries with backoff for the API step, set a suitable timeout, and use mocks for non-critical dependencies.

Syntax over Promises: an async function returns a Promise and await pauses until it resolves. Every Playwright action returns a Promise, so you await each step.

Use dotenv files per environment, read them in playwright.config and set baseURL and credentials from variables, selecting with an ENV flag.

A function that remembers variables from its outer scope even after that scope has finished. They are used for private state and factory helpers.

Use --debug or the Inspector, page.pause(), UI mode, the trace viewer and headed runs with slowMo.

Use the request fixture: const res = await request.get('/api/users'); expect(res.ok()).toBeTruthy(); const body = await res.json();

Use npx playwright test --shard=1/4 in each CI job and merge reports afterwards to reduce total run time.

POST the query and variables as JSON to the single endpoint and assert both data and errors fields in the response.

Functions that take other functions as arguments or return them, such as map, filter and reduce, or a helper that wraps retry logic around a test step.

A class receives page in its constructor, stores locators as properties and exposes actions like login(user, pass). Tests call page objects, not raw locators.

Use request.post with multipart: { file: { name, mimeType, buffer } } and assert the response and stored file details.

npm is the Node package manager. package.json lists the project's dependencies and scripts, such as the command that runs the tests.

An object describing how to find an element, re-evaluated on every action so it always targets the current DOM.

test.step groups actions into named steps in reports; annotations such as test.skip, test.fixme and test.slow communicate intent and adjust behaviour.

Rely on auto-waiting plus a web-first assertion on the final state, disable animations in config for tests and avoid fixed timeouts.

Use the official Playwright image which contains browsers and dependencies, mount the project and run npx playwright test for consistent CI environments.

Assert the status with expect(res.status()).toBe(200), parse res.json() and check fields, using schema validation for the structure.

locator.hover() and locator.dragTo(target) perform these actions, with auto-waiting for actionability.

var is function-scoped and hoisted. let and const are block-scoped; const can't be reassigned (though an object it points to can change). Prefer const, then let.

Capture the download event, save it with download.saveAs, then read the file in Node and assert on name, size or content.

setInputFiles on the input for uploads; for downloads wait on page.waitForEvent('download') and save or inspect the file.

User-facing ones: getByRole, getByText, getByLabel, getByPlaceholder and getByTestId, which are more resilient than CSS or XPath.

Playwright locators pierce open shadow roots by default, so getByRole and CSS locators work without special handling.

Declarations of var and functions are moved to the top of their scope at compile time; let and const are hoisted but stay in the temporal dead zone until declared.

Add tags in the title (@smoke) or use the tag option, and run with --grep @smoke or --grep-invert.

Use timeout and expect.timeout in config, test.setTimeout() for one test and test.slow() for known slower tests.

await request.post('/api/users', { data: { name: 'Asha' } }) automatically sets JSON headers and serialises the payload.

Log in once in a setup project, save storageState to a file and reuse it in other projects or tests.

An open-source end-to-end testing framework from Microsoft that automates Chromium, Firefox and WebKit through one API, in multiple languages.

all waits for every promise and rejects on the first failure; allSettled waits for all and reports each outcome; race settles with the first one to finish.

Strings in backticks that allow embedded expressions like `Hello ${name}` and multi-line text, useful for building dynamic locators and URLs.

TypeScript adds static types on top of JavaScript and compiles to it. Types catch errors early and give better autocomplete, which helps in larger test suites.

click simulates a real user click with actionability checks; dispatchEvent fires a DOM event directly without those checks.

Click to open the control, then use getByRole('option') or a text locator for the target item, instead of relying on fragile index-based selectors.

Auto-waiting, a built-in test runner, Chromium/Firefox/WebKit with one API, network interception, the trace viewer and parallel runs out of the box — usually faster and less flaky.

Placeholders for types that make reusable code type-safe, for example a helper function returning the same type of item that it receives.

In a fixture or beforeEach, call the API (request.post) to create the user or order, use it in the UI test, then delete it in teardown. It is faster and more reliable than creating data through the UI.

undefined means a variable has not been assigned; null is an intentional empty value.

npx playwright test tests/login.spec.ts, add -g "test title" to match a name, or use test.only while debugging.

Use page.route to intercept the call and fulfil it with fixed JSON so tests do not depend on external systems.

Use page.frameLocator('#frame').getByRole(...) so actions work inside the iframe with auto-waiting.

Cover happy path, validation errors, auth and permissions, boundary values, idempotency, schema, performance and data cleanup.

Both describe object shapes. Interfaces can be extended and merged; type aliases can also describe unions and primitives. Use interfaces for page or test-data shapes, types for unions.

Record timestamps around the request or use response timing, then assert the duration is under an agreed threshold.

Run npm init playwright@latest, which sets up config, example tests and browsers; execute with npx playwright test.

Separate tests, page objects, fixtures, utilities, test data and config; use tags, projects, shared auth setup, linting, code review and a CI pipeline with sharding and reports.

List, dot, line, HTML, JSON and JUnit reporters, plus integrations such as Allure, configurable per environment.

Wait for the popup event with const [popup] = await Promise.all([page.waitForEvent('popup'), page.click('a')]), then interact with popup.

beforeEach runs the same code before every test in scope; fixtures are lazy, composable and only set up what a test uses.

Playwright supports multiple browsers, tabs, languages and has auto-waiting and tracing; Selenium has the widest ecosystem; Cypress runs in-browser with a great UI but has more limits across tabs.

Scripts that run once before or after the whole run, for seeding data, starting services or creating authentication state.

waitForSelector is a lower-level wait; locator assertions are preferred as they retry and are more readable.