docs/developer_portal/guidelines/frontend-style-guidelines.md

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title: Frontend Style Guidelines
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# Frontend Style Guidelines

This is a list of statements that describe how we do frontend development in Superset. While they might not be 100% true for all files in the repo, they represent the gold standard we strive towards for frontend quality and style.

*   We develop using TypeScript.
*   We use React for building components, and Redux to manage app/global state.
    *   See: [Component Style Guidelines and Best Practices](./frontend/component-style-guidelines)
*   We prefer functional components to class components and use hooks for local component state.
*   We use [Ant Design](https://ant.design/) components from our component library whenever possible, only building our own custom components when it's required.
*   We use [@emotion](https://emotion.sh/docs/introduction) to provide styling for our components, co-locating styling within component files.
    *   See: [Emotion Styling Guidelines and Best Practices](./frontend/emotion-styling-guidelines)
*   We use Jest for unit tests, React Testing Library for component tests, and Cypress for end-to-end tests.
    *   See: [Testing Guidelines and Best Practices](./frontend/testing-guidelines)
*   We add tests for every new component or file added to the frontend.
*   We organize our repo so similar files live near each other, and tests are co-located with the files they test.
*   We prefer small, easily testable files and components.
*   We use ESLint and Prettier to automatically fix lint errors and format the code.
    *   We do not debate code formatting style in PRs, instead relying on automated tooling to enforce it.
    *   If there's not a linting rule, we don't have a rule!
*   We use [React Storybook](https://storybook.js.org/) and [Applitools](https://applitools.com/) to help preview/test and stabilize our components