React 17's automatic JSX runtime for your entire bundle

• Replaces React.createElement calls in your entire bundle (even for pre-minified, compiled React components from node_modules) with the automatic JSX runtime introduced in React 17
• Injects import React statements in server mode, but not for modules where React is already imported
• Deduplicates react and react-dom imports by setting resolve.dedupe for you

• What are the benefits of using the new JSX runtime?

  1. You don't need to import React manually anymore.
  2. Better performance now and in the future. The Motivations section in the RFC explains the specifics of performance issues with React.createElement.
  3. In the future, you won't need React.forwardRef anymore.
  4. Depending on your setup, slightly smaller bundle sizes (according to the React team).
  5. Faster parsing of JavaScript by web browser (.createElement cannot be minified).

• How much does this affect Vite's performance?
  In serve mode, the performance effects are unnoticeable, since Babel is only used when bundling.
  Otherwise, you'll see ~40% longer build times in the ./demo folder, but this % largely depends on how many kB of JavaScript need to be parsed and transformed by Babel.

• Do I need React 17+ to use the new JSX runtime?
  No. Support for the new runtime was backported to React 16.14.0, React 15.7.0, and React 0.14.10.

import reactJsx from 'vite-react-jsx'

export default {
  plugins: [
    reactJsx(),
  ]
}