message: Support while and case
diff: @@ -593,14 +593,23 @@ export const plugin: Plugin = {
  result += `each ${token.val} in ${token.code}`;
  break;
  case 'while':
  + result = printIndent(previousToken, result, indent, indentLevel);
  + result += `while ${token.val}`;
  break;
  case 'case':
  + result = printIndent(previousToken, result, indent, indentLevel);
  + result += `case ${token.val}`;
  break;
  case 'when':
  + result = printIndent(previousToken, result, indent, indentLevel);
  + result += `when ${token.val}`;
  break;
  case ':':
  + result += ': ';
  break;
  case 'default':
  + result = printIndent(previousToken, result, indent, indentLevel);
  + result += 'default';
  break;
  default:
  throw new Error('Unhandled token: ' + JSON.stringify(token));
  