TCS Playwright Testing Interview Questions & Answers

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

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

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.

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.

Destructuring pulls values from arrays or objects into variables; spread expands an array or object into another, useful for copying and merging config.

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.

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

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.

await page.route('**/api/users', route => route.fulfill({ status: 200, json: [{ id: 1, name: 'Test' }] }) );

It records screenshots, DOM snapshots, network calls and actions per step so you can replay a failed run and see exactly what happened.

Files run in parallel by default; set workers in the config and use test.describe.configure({ mode: 'parallel' }) for tests inside a file.

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

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

A short function syntax that does not have its own this and arguments, taking them from the surrounding scope.

Use try-catch with await, or .catch() on promises, and make sure rejected promises are never left unhandled.

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

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

JavaScript runs one call stack and uses queues for async work; the event loop pushes callbacks from the microtask (promises) and task queues when the stack is empty.

Log in with request.post, call request.storageState(), and create a browser context using that state.

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

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

Tag tests (in the title or with { tag: '@smoke' }) and run: npx playwright test --grep @smoke (use --grep-invert to exclude).

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.

Set extraHTTPHeaders in the config or pass headers per request, for example Authorization: Bearer token fetched in a setup step.

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

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

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.

API testing checks services directly and is fast and stable; UI testing checks the full user experience in the browser and is slower.

Create test data through API calls, verify it in the UI and clean up via API, which makes UI tests faster and more reliable.

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

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

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

Turn on trace: 'on-first-retry', open the trace viewer, check network and timing, replace hard waits with web-first assertions, isolate test data and check for sharding conflicts.

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.

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.

Use page.waitForResponse(res => res.url().includes('/api/orders') && res.ok()) together with the action that triggers it.

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

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

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.

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

Use expect(page).toHaveScreenshot() to compare with stored baselines, with thresholds and masks for dynamic regions.

page.screenshot() for captures and config options use: { screenshot: 'only-on-failure', video: 'retain-on-failure' } for automatic evidence.

The action runs without waiting, so the next step may run first — causing flaky failures or 'Target closed' errors. The @typescript-eslint/no-floating-promises rule catches it.

TypeScript + POM + custom fixtures, environment configs, API helpers for test data, tags like @smoke, sharding across CI machines, retries with traces, HTML/Allure reports, lint and review rules.

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

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

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

const [download] = await Promise.all([ page.waitForEvent('download'), page.getByText('Export').click(), ]); await download.saveAs('reports/file.csv');

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

A Locator is lazy, re-resolved on every action and auto-waits (recommended). An ElementHandle points to one DOM node and can go stale.

Use a library such as zod or ajv to define the expected schema and parse the response to fail on missing or wrongly typed fields.

Both describe the shape of data. Interfaces are extendable and suit object contracts; type aliases can also model unions and primitives.

Set retries in the config or CLI and failed tests re-run in a fresh context, with trace recorded on first retry to diagnose flakiness.

Register page.on('dialog', d => d.accept()) before the action triggers the dialog.

const [newPage] = await Promise.all([ context.waitForEvent('page'), page.getByText('Open').click(), ]); await newPage.waitForLoadState();

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

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(); });

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.

Fetch tokens in a fixture with expiry tracking and refresh it when it is about to expire, keeping tests unaware of the details.

Synchronous code runs line by line and blocks; asynchronous code starts a task and continues, handling the result later with promises or await.

Create a class that takes a page, defines locators as properties and exposes action methods; instantiate it in a fixture for clean tests.

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

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.

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

A browser is the engine instance; a context is an isolated session (cookies, storage); a page is a tab inside a context.

The object behind the request fixture that holds base URL, headers and cookies, and can share cookies with a browser context.

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

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.

await expect(page).toHaveScreenshot('home.png') compares against a baseline image; tune maxDiffPixels and mask dynamic areas like dates.

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

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

Fixtures set up and tear down test dependencies. Extend with test.extend({ loggedInPage: async ({ page }, use) => { ...; await use(page); } }).

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

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