parseString method

@override int parseString(int i, FContext ctxt)

Implementation

@override
int parseString(int i, FContext ctxt) {
  final k = parseStringSimple(i + 1, ctxt);

  if (k != -1) {
    ctxt.addStringLimit(atRange(i + 1, k - 1), i, k);
    return k;
  }

  int j = i + 1;
  final sb = StringBuffer();

  int c = byte(j) & 0xff;

  while (c != 34) {
    if (c == 92) {
      final b = byte(j + 1);

      switch (b) {
        case 98:
          sb.write('\b');
          j += 2;
        case 102:
          sb.write('\f');
          j += 2;
        case 110:
          sb.write('\n');
          j += 2;
        case 114:
          sb.write('\r');
          j += 2;
        case 116:
          sb.write('\t');
          j += 2;

        case 34:
          sb.write('"');
          j += 2;
        case 47:
          sb.write('/');
          j += 2;
        case 92:
          sb.write('\\');
          j += 2;

        // if there's a problem then descape will explode
        case 117:
          final jj = j + 2;
          sb.write(descape(jj, atRange(jj, jj + 4)));
          j += 6;

        default:
          die(
            j,
            'invalid escape sequence (\\${String.fromCharCode(b)})',
            chars: 1,
          );
      }
    } else if (c < 32) {
      die(j, 'control char ($c) in string', chars: 1);
    } else if (c < 128) {
      // 1-byte UTF-8 sequence
      sb.write(String.fromCharCode(c));
      j += 1;
    } else if ((c & 224) == 192) {
      // 2-byte UTF-8 sequence
      sb.write(atRange(j, j + 2));
      j += 2;
    } else if ((c & 240) == 224) {
      // 3-byte UTF-8 sequence
      sb.write(atRange(j, j + 3));
      j += 3;
    } else if ((c & 248) == 240) {
      // 4-byte UTF-8 sequence
      sb.write(atRange(j, j + 4));
      j += 4;
    } else {
      die(j, 'invalid UTF-8 encoding');
    }

    c = byte(j) & 0xff;
  }

  j += 1;

  ctxt.addStringLimit(sb.toString(), i, j);
  return j;
}