Cognizant Playwright Testing Interview Questions & Answers

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

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

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.

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.

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

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

Named configurations that run the same tests across different browsers, devices or environments.

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

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

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

Log in once in global setup, save storageState to a JSON file and set use.storageState in the config so every test starts logged in.

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.

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

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

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

map transforms each item, filter keeps items that match a condition, and reduce combines all items into a single value.

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

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

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

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

Send invalid payloads or missing auth and assert 400, 401 or 404 codes and the error message bodies.

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

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.

Read the next page link or IDs from earlier responses, loop until done and assert counts and uniqueness; pass IDs between calls in the same test.

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

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.

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

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

Use environment variables or .env files, a baseURL in config, API calls for setup and cleanup, and unique data per run.

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

await expect.soft(locator).toHaveText('...') records the failure but lets the test continue, so you see every mismatch in one run.

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

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

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

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

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

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.

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.

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

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

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.

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

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.

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

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

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

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

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

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

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

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

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

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

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

Run in parallel with sharding, reuse authentication state, set up data through APIs, avoid unnecessary waits, run smoke on every commit and the full suite nightly.

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.

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

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

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

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

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

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

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

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

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.

npx playwright codegen records user actions and generates test code with suggested locators, handy for starting tests.

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.