src/language-js/pragma.js/insertPragma
function insertPragma(originalText) {
  const { shebang, text, pragmas, comments } = parseDocBlock(originalText);
  const strippedText = strip(text);

  const docBlock = print({
    pragmas: {
      format: "",
      ...pragmas,
    },
    comments: comments.trimStart(),
  });

  return (
    (shebang ? `${shebang}\n` : "") +
    // normalise newlines (mitigate use of os.EOL by jest-docblock)
    normalizeEndOfLine(docBlock) +
    (strippedText.startsWith("\n") ? "\n" : "\n\n") +
    strippedText
  );
}