Awesome

eslint-plugin-react-refresh

Validate that your components can safely be updated with fast refresh.

Limitations

⚠️ To avoid false positive, by default this plugin is only applied on tsx & jsx files. See options to run on JS files. ⚠️

The plugin rely on naming conventions (i.e. use PascalCase for components, camelCase for util functions). This is why there are some limitations:

export * are not supported and will be reported as an error
Anonymous function are not supported (i.e export default function() {})
Class components are not supported
All-uppercase function export is considered an error when not using direct named export (ex const CMS = () => <></>; export { CMS })

Installation

npm i -D eslint-plugin-react-refresh

Usage

{
  "plugins": ["react-refresh"],
  "rules": {
    "react-refresh/only-export-components": "warn"
  }
}

Flat config

import reactRefresh from "eslint-plugin-react-refresh";

export default [
  {
    // in main config for TSX/JSX source files
    plugins: {
      "react-refresh": reactRefresh,
    },
    rules: {
      "react-refresh/only-export-components": "warn",
    },
  },
];

Fail

export const foo = () => {};
export const Bar = () => <></>;

export default function () {}
export default compose()(MainComponent)

export * from "./foo";

const Tab = () => {};
export const tabs = [<Tab />, <Tab />];

const App = () => {};
createRoot(document.getElementById("root")).render(<App />);

Pass with allowConstantExport

export const CONSTANT = 3;
export const Foo = () => <></>;

Pass

export default function Foo() {
  return <></>;
}

const foo = () => {};
export const Bar = () => <></>;

import { App } from "./App";
createRoot(document.getElementById("root")).render(<App />);

Options

allowExportNames (v0.4.4)

If you use a framework that handles HMR of some specific exports, you can use this option to avoid warning for them.

Example for Remix:

{
  "react-refresh/only-export-components": [
    "warn",
    { "allowExportNames": ["meta", "links", "headers", "loader", "action"] }
  ]
}

allowConstantExport (v0.4.0)

Don't warn when a constant (string, number, boolean, templateLiteral) is exported aside one or more components.

This should be enabled if the fast refresh implementation correctly handles this case (HMR when the constant doesn't change, propagate update to importers when the constant changes.). Vite supports it, PR welcome if you notice other integrations works well.

{
  "react-refresh/only-export-components": [
    "warn",
    { "allowConstantExport": true }
  ]
}

checkJS (v0.3.3)

If your using JSX inside .js files (which I don't recommend because it forces you to configure every tool you use to switch the parser), you can still use the plugin by enabling this option. To reduce the number of false positive, only files importing react are checked.

{
  "react-refresh/only-export-components": ["warn", { "checkJS": true }]
}