Lodestar snappy checksum issue

	case chunkTypeUncompressedData:
			// Section 4.3. Uncompressed data (chunk type 0x01).
			if chunkLen < checksumSize {
				r.err = ErrCorrupt
				return r.err
			}
			buf := r.buf[:checksumSize]
			if !r.readFull(buf, false) {
				return r.err
			}
			checksum := uint32(buf[0]) | uint32(buf[1])<<8 | uint32(buf[2])<<16 | uint32(buf[3])<<24
			// Read directly into r.decoded instead of via r.buf.
			n := chunkLen - checksumSize
			if n > len(r.decoded) {
				r.err = ErrCorrupt
				return r.err
			}
			if !r.readFull(r.decoded[:n], false) {
				return r.err
			}
			if crc(r.decoded[:n]) != checksum {
				r.err = ErrCorrupt
				return r.err
			}
			r.i, r.j = 0, n
			continue

uncompress(chunk: Uint8ArrayList): Uint8ArrayList | null {
    this.buffer.append(chunk);
    const result = new Uint8ArrayList();
    while (this.buffer.length > 0) {
      if (this.buffer.length < 4) break;

      const type = getChunkType(this.buffer.get(0));
      const frameSize = getFrameSize(this.buffer, 1);

      if (this.buffer.length - 4 < frameSize) {
        break;
      }

      const data = this.buffer.subarray(4, 4 + frameSize);
      this.buffer.consume(4 + frameSize);

      if (!this.state.foundIdentifier && type !== ChunkType.IDENTIFIER) {
        throw "malformed input: must begin with an identifier";
      }

      if (type === ChunkType.IDENTIFIER) {
        if (!Buffer.prototype.equals.call(data, IDENTIFIER)) {
          throw "malformed input: bad identifier";
        }
        this.state.foundIdentifier = true;
        continue;
      }

      if (type === ChunkType.COMPRESSED) {
        result.append(uncompress(data.subarray(4)));
      }
      if (type === ChunkType.UNCOMPRESSED) {
1)        result.append(data.subarray(4));
      }
    }
    if (result.length === 0) {
      return null;
    }
    return result;
  }