This PR implements the only-export-components rule from eslint-plugin-react-refresh with comprehensive configuration support to ensure files only export React components for proper Fast Refresh/Hot Module Replacement functionality.

What this rule does

The rule validates that files containing React components follow patterns that work correctly with Fast Refresh:

• Prevents export-all declarations: export * from "./foo" cannot be verified to only export components
• Requires named exports: Anonymous function exports like export default function() {} break Fast Refresh
• Enforces component-only exports: Mixing component and non-component exports prevents proper hot reloading
• Detects local components: Components that exist but aren't exported should either be exported or moved to separate files
• Separates React contexts: Context objects should be in separate files from components

Configuration Options

The rule supports all configuration options from the original eslint-plugin-react-refresh:

• allowConstantExport: Allow exporting constants alongside components
• allowExportNames: Allow specific export names (array of strings)
• customHOCs: Support for custom Higher-Order Components (array of strings)
• checkJS: Support for JSX in .js files (extends beyond just .jsx/.tsx)

Enhanced Features

• Component Name Detection: Supports underscores in component names (My_Component)
• Comprehensive HOC Support: Built-in support for memo, forwardRef, connect, withRouter, observer, plus custom HOCs
• Class Components: Full detection and support for React class components
• Function Expressions: Detects function expressions as components
• React Context Detection: Identifies createContext() and React.createContext() calls
• Type-only Exports: Properly handles TypeScript type-only exports
• Enhanced File Detection: Recognizes test files in __tests__ directories and various test file patterns

Examples

❌ Incorrect - Mixed exports break Fast Refresh:

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

✅ Correct with allowConstantExport - Constants allowed with configuration:

// With { "allowConstantExport": true }
export const CONSTANT = 3;
export const Component = () => <></>;

✅ Correct - Component-only exports work with Fast Refresh:

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

export const AnotherComponent = memo(() => <></>);

The implementation follows oxc's patterns and integrates seamlessly with the existing React plugin, providing full compatibility with projects migrating from ESLint to OXC.

Fixes #8698.

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