Playwright vs Chai comparison of testing frameworks
What are the differences between Playwright and Chai?

	Playwright https://playwright.dev	Chai https://www.chaijs.com
Programming language	JavaScript	JavaScript
Category	End-to-End Testing	Unit Testing
General info	Test across all modern browsers. Use in your preferred language. Single API to automate Chromium, Firefox and WebKit. Use the Playwright API in JavaScript & TypeScript, Python, .NET and, Java.	Chai is a BDD / TDD assertion library for Node.js and the browser that can be paired with any JavaScript testing framework. Chai is an assertion library, similar to Node's built-in assert and makes testing easier by giving you many assertions you can run against your code. It also includes a robust Plugin architecture for extending Chai's assertions and interfaces.
xUnit Set of frameworks originating from SUnit (Smalltalk's testing framework). They share similar structure and functionality.	Yes While using xUnit is supported, it does not support running parallel tests. https://playwright.dev/dotnet/docs/test-runners/#xunit-support	N/A
Client-side Allows testing code execution on the client, such as a web browser	Yes Test on Chromium, Firefox and WebKit. Playwright has full API coverage for all modern browsers, including Google Chrome and Microsoft Edge (with Chromium), Apple Safari (with WebKit) and Mozilla Firefox. Cross-platform WebKit testing. With Playwright, test how your app behaves in Apple Safari with WebKit builds for Windows, Linux and macOS. Test locally and on CI. Test for mobile. Use device emulation to test your responsive web apps in mobile web browsers. Headless and headed. Playwright supports headless (without browser UI) and headed (with browser UI) modes for all browsers and all platforms. Headed is great for debugging, and headless is faster and suited for CI/cloud executions.	Yes Chai can be used in a browser environment to test front-end components and functionality
Server-side Allows testing the bahovior of a server-side code	Yes While running tests inside browsers you may want to make calls to the HTTP API of your application. It may be helpful if you need to prepare server state before running a test or to check some postconditions on the server after performing some actions in the browser. All of that could be achieved via APIRequestContext methods.	Yes Chai is used in a Node.JS environment to test server behaviour and functionality
Fixtures Allows defining a fixed, specific states of data (fixtures) that are test-local. This ensures specific environment for a single test	Yes Playwright Test is based on the concept of the test fixtures. Test fixtures are used to establish environment for each test, giving the test everything it needs and nothing else. Test fixtures are isolated between tests, which gives Playwright Test following benefits: Playwright Test runs tests in parallel by default, making your test suite much faster; Playwright Test can efficiently retry the flaky failures, instead of re-running the whole suite; You can group tests based on their meaning, instead of their common setup. Learn more at https://playwright.dev/docs/test-fixtures	N/A
Group fixtures Allows defining a fixed, specific states of data for a group of tests (group-fixtures). This ensures specific environment for a given group of tests.	Yes You can group tests based on their meaning, instead of their common setup.	N/A
Generators Supports data generators for tests. Data generators generate input data for test. The test is then run for each input data produced in this way.	Yes Playwright comes with the ability to generate tests out of the box. Generate tests; Preserve authenticated state; Record using custom setup; Emulate devices; Emulate color scheme and viewport size; Emulate geolocation, language and timezone. Learn more at https://playwright.dev/docs/codegen/	Yes By using chai-spec-generator plugin which will generate chai test specs from a JavaScript object
Licence Licence type governing the use and redistribution of the software	Apache License 2.0	MIT License
Mocks Mocks are objects that simulate the behavior of real objects. Using mocks allows testing some part of the code in isolation (with other parts mocked when needed)	Yes Playwright introduces context-wide network interception to stub and mock network requests. You can mock API endpoints via handling the network quests in your Playwright script. Learn more at https://playwright.dev/docs/network/#handle-requests	Yes By using by using a third party library like chai-jest-mocks which is a chai plugin that adds assertions for jest mock functions. You can also use sinon.js
Grouping Allows organizing tests in groups	Yes You can group tests to give them a logical name or to scope before/after hooks to the group.	N/A
Other Other useful information about the testing framework	You can use the Playwright API in JavaScript & TypeScript, Python, .NET and, Java.