code: function readFixed64(/* this: Reader */) {
  
      /* istanbul ignore if */
      if (this.pos + 8 > this.len)
          throw indexOutOfRange(this, 8);
  
      return new LongBits(readFixed32_end(this.buf, this.pos += 4), readFixed32_end(this.buf, this.pos += 4));
  }
docs: /* eslint-disable no-invalid-this