Re: [PATCH] Optimize json_lex_string by batching character copying

> +           if (copyable_characters_length)
> +           {
> +               /* flush copyable characters */
> +               appendBinaryStringInfo(
> +                                      lex->strval,
> +                                      s - copyable_characters_length,
> +                                      copyable_characters_length);
> +
> +           }
>            break;
>
> I wonder why copyable_characters_length is not reset after flushing.

It breaks from the loop right after. So copyable_characters_length isn't used
again and thus resetting is not necessary. But I agree this could use a comment.