src/main/multiparser.js/printSubtree
function printSubtree(path, print, options, printAstToDoc) {
  if (options.printer.embed && options.embeddedLanguageFormatting === "auto") {
    return options.printer.embed(
      path,
      print,
      (text, partialNextOptions) =>
        textToDoc(text, partialNextOptions, options, printAstToDoc),
      options
    );
  }
}