Function splitBlock

packages/localize/src/utils/src/messages.ts:319–329

(cooked: string, raw: string)

 * @throws an error if the `block` is unterminated
 */
export function splitBlock(cooked: string, raw: string): {text: string; block?: string} {
  if (raw.charAt(0) !== BLOCK_MARKER) {
    return {text: cooked};
  } else {
    const endOfBlock = findEndOfBlock(cooked, raw);
    return {
      block: cooked.substring(1, endOfBlock),
      text: cooked.substring(endOfBlock + 1),
    };
  }
}

function computePlaceholderName(index: number) {
  return index === 1 ? 'PH' : `PH_${index - 1}`;