#unit testing

Component testing is a gray area between integration and unit testing. The demo app focuses on the cart component and writing test cases for Playwright component test and VTest. The first cart test encounters a bug with the invisible method in View Test.

This Talk discusses the challenges of testing in React and React Native applications, particularly with regards to barcode scanning. It explores the violation of separation of concerns in React and proposes the use of the HumbleObject model to simplify testing and improve code cleanliness. The MVP model is also introduced as a way to separate UI state and logic from the component. The importance of following patterns, standardization, and teaching principles is emphasized, along with the benefits of using custom hooks to share business logic. The potential of AI tools in code refactoring is mentioned as well.

This Talk introduces Test Effective Development, a new approach to testing that aims to make companies more cost-effective. The speaker shares their personal journey of improving code quality and reducing bugs through smarter testing strategies. They discuss the importance of finding a balance between testing confidence and efficiency and introduce the concepts of isolated and integrated testing. The speaker also suggests different testing strategies based on the size of the application and emphasizes the need to choose cost-effective testing approaches based on the specific project requirements.

The Talk discusses the evolution of test automation from the original test automation pyramid to the testing pyramid. It explores modern approaches to UI component testing, including isolations and testing with a fake DOM. The importance of testing in a real browser and the emergence of tools like Selenium, WebDriver.io, Puppeteer, Cypress, and PlayWrite for browser automation are highlighted. The advantages of out-of-process browser automation are explained, along with the use of Storybook and Playwright for testing components. The distinction between end-to-end testing and component testing is also mentioned.

This Talk is about a developer's first open source contribution to the Testing Library, exploring how it works and its importance in testing. It discusses the challenges of testing in a Node environment and the use of getByRole query to find elements. The Talk also highlights the complexities of implicit roles and the need for specific attributes to filter elements. It emphasizes the importance of verifying visibility and accessibility when querying elements and the process of test clean up.

MSW is an API mocking library that simplifies the process of intercepting requests and mocking responses. It leverages standard JavaScript APIs like the ServiceWorker API and the Fetch API. MSW has seen significant adoption, with over 90,000 projects on GitHub and 2.5 million weekly downloads on npm. The recent release of Node.js 18 has allowed for refactoring and simplification in MSW. MSW supports TypeScript and can be used for contract testing with tools like PACT I-O.

This Talk explores the challenges of choosing and learning testing frameworks, emphasizing the importance of planning, automation, and prioritizing unit testing. The VTEST framework is introduced as a fast and stable option for unit testing JavaScript and TypeScript code, with a focus on logic and mocking external dependencies. The Talk also covers testing React hooks, integration testing with TestingLibraryReact, component testing, and achieving code coverage. Best practices include performing accessibility tests, planning tests before coding, and using data test IDs for stability.

Today's Talk introduces VEST, a form validation framework that combines the syntax and style of Unitest with form validation. The lack of structure in form validation is a major problem, leading to messy and difficult-to-maintain code. Testing forms and form validation can be challenging, especially with complex logic. VEST offers a solution by allowing the creation of a form validation suite using unit tests. It provides features like multiple validations per field, async validations, and memoization, with support for any JavaScript environment and full TypeScript support.

This talk explores unit testing in Angular applications, covering topics such as testing front-end applications, specifics of testing Angular, best practices, and educational resources. It discusses the anatomy of a unit test in both Jasmine and Jest, the setup and initial tests in Angular, testing user interaction and event handlers, testing rendered output and change detection, and unit testing parent components with child components. It also highlights best practices like using test doubles, testing components with dependency injection, and considerations for unit testing. Code coverage is emphasized as a metric that doesn't guarantee bug-free code.

This Talk provides ways to catch accessibility defects during testing, including adding accessibility testing to a website for Studio Ghibli using React, NX, Jazz, JazzX, Cypress, and CypressX. The importance of unitizing components and conducting end-to-end testing with Cypress and CypressX is emphasized to ensure accessibility. The process of setting up CypressX testing is explained, highlighting the use of typings and the CypressX support file. These tools make it easier for developers to avoid accessibility bugs during development.

This Talk explores the pain points and best practices in software testing, emphasizing the importance of simplicity and comprehensibility in test design. It discusses techniques such as the three-part rule for test titles, the triple-A pattern for test structure, and the use of clear and descriptive names in tests. The Talk also highlights the traps of testing implementation details and using fixed waiting times. The speaker encourages teamwork and learning from experience to improve testing practices.

The Talk discusses testing hooks in a React application. The speaker starts by showing an untested React application and begins testing with a simple placeholder test. The importance of refactoring and testing custom hooks is emphasized, with the recommendation to use the React hooks library and achieve full test coverage. Unit testing React components may not be valuable, as the complexity lies in the hook code. Instead, end-to-end testing with tools like Cypress is recommended.