@mui/internal-docs-infra/ChunkProvider/PreloadProvider.mjs

MUI Infra - internal documentation creation tools.

'use client';

import * as React from 'react';
import { PreloadContext } from "./PreloadContext.mjs";

/**
 * Scopes a cross-instance preload cache (typically at a layout). Descendants
 * call `usePreload` to start dynamic imports of shared helpers keyed by a
 * stable string; the first call per key runs the factory and every other
 * instance reuses its promise - so a helper a chunk's data implies (a transform
 * fn, say) is fetched once, in parallel with the content, across the page.
 */
import { jsx as _jsx } from "react/jsx-runtime";
export function PreloadProvider({
  children
}) {
  // One cache per provider instance, stable across renders.
  const [cache] = React.useState(() => new Map());
  const preload = React.useCallback((key, factory) => {
    const existing = cache.get(key);
    if (existing) {
      // Same key -> same factory type by contract; the consumer owns the keying.
      return existing;
    }
    const promise = factory();
    cache.set(key, promise);
    return promise;
  }, [cache]);
  return /*#__PURE__*/_jsx(PreloadContext.Provider, {
    value: preload,
    children: children
  });
}