async function load(href, context, nextLoad) {
    const url = new URL(href)
    const [regex, process] = settings

    if (url.protocol === 'file:' && regex.test(url.pathname)) {
      const value = await fs.readFile(url)
      const file = await process(new VFile({value, path: url}))

      /* c8 ignore next 3 -- hard to test. */
      if (file.messages.length > 0) {
        console.error(reporter(file))
      }

      return {
        format: 'module',
        shortCircuit: true,
        source:
          String(file) +
          '\n//# sourceMappingURL=data:application/json;base64,' +
          Buffer.from(JSON.stringify(file.map)).toString('base64') +
          '\n'
      }
    }

    return nextLoad(href, context)
  }
Load `file:` URLs to MD(X) files.

@param {string} href
  URL.
@param {LoadHookContext} context
  Context.
@param {NextLoad} nextLoad
  Next or default `load` function.
@returns {Promise<LoadFnOutput>}
  Result.
@satisfies {LoadHook}