Miyoo mini: Error loading cart lua

[realjackwang]

With the newest version. some of the games works, but some didn't.

this game can get into the command line, but said Error loading cart lua: https://www.lexaloffle.com/bbs/cposts/bi/birdswithguns-3.p8.png

this game crashed directly: https://www.lexaloffle.com/bbs/cposts/pi/picochill-1.p8.png

[jtothebell]

Thanks for the report. I have a potential fix for birds with guns that needs some more regression testing but hopefully will make it into the next release. I wasn't aware of a crash in Pico & Chill, so I will take a look at that one.

[nckstwrt]

The birds with guns fix I came up was to basically put part of the old Lua 5.1 and lower nested comments code back in read_long_string (llex.c). So from: https://www.lua.org/source/5.1/llex.c.html#read_long_string <--- that's a mess, but you only have to add a few lines to our version to make it work. So mine ended up like:

static void read_long_string (LexState *ls, SemInfo *seminfo, int sep) {
  int cont = 0;
  save_and_next(ls);  /* skip 2nd `[' */
  if (currIsNewline(ls))  /* string starts with a newline? */
    inclinenumber(ls);  /* skip it */
  for (;;) {
    switch (ls->current) {
      case EOZ:
        lexerror(ls, (seminfo) ? "unfinished long string" :
                                 "unfinished long comment", TK_EOS);
        break;  /* to avoid warnings */
    case '[': {
            save_and_next(ls);
            if (ls->current == '[') {
                save_and_next(ls);  /* skip 2nd `[' */
                cont++;
            }
            break;
        }
      case ']': {
        if (skip_sep(ls) == sep) {
          save_and_next(ls);  /* skip 2nd `]' */
          cont--;
          if (cont >= 0)
              break;
          goto endloop;
        }
        break;
      }
      case '\n': case '\r': {
        save(ls, '\n');
        inclinenumber(ls);
        if (!seminfo) luaZ_resetbuffer(ls->buff);  /* avoid wasting space */
        break;
      }
      default: {
        if (seminfo) save_and_next(ls);
        else next(ls);
      }
    }
  } endloop:
  if (seminfo)
    seminfo->ts = luaX_newstring(ls, luaZ_buffer(ls->buff) + (2 + sep),
                                     luaZ_bufflen(ls->buff) - 2*(2 + sep));
}

^ Additional lines added in bold

birds with guns is a pretty good test suite as it uses long strings/comments through out. So the fact that it works with that (and everything else I've tried) - makes me think this is good.

[jtothebell]

So this is pretty similar to the fix I had attempted earlier (see https://github.com/jtothebell/z8lua/commit/60bf3fd7a314f5dea3082fc4b020f05613e9ef9f), but both do have regressions for some carts like https://www.lexaloffle.com/bbs/?pid=37199 and https://www.lexaloffle.com/bbs/?pid=53256 which work prior to this change but then fail afterward because apparently Pico-8 allows multiple long comment opening symbols without their corresponding close (treats them as single line comments if they don't have a close it looks like to me)

That being said, from my test suite of carts it looks like it is a net gain in compatibility and seems to be worth including at least for the time being.