Luigi's Mansion silently stops working

[Toad06]

Edit 2020-11-29:
The game now works but there's still an unexpected behavior - please see the tests in the comments below.

---

After the ghost has reached the top of the screen, a sound effect plays and then nothing else happens anymore.
No error and no warning in the console.

Expected (Flash Player):

Game:
luigimansion.zip

[CUB3D]

This failing test case may be causing some of the issues here, it seems like something to do with the order of onEnterFrame or onDestroy calls but I'm not sure.

Test:
clip_destruction.zip

[Toad06]

Thanks for investigating this issue!
I've tested the file again and for some reason, the game just "works" if you remove some Destroy() calls (removeMovieClip). But that's weird.

IntroScreen.prototype.onEnterFrame = function()
{
   if(IntroKong0._y < 168)
   {
      IntroKong0.removemovieclip();
      _root.attachMovie("StartScreen","StartScreen0",1);
      this.Destroy(); // remove this
   }
};

=> Removing this allows the game to start but platforms won't be visible.

StartScreen.prototype.onEnterFrame = function()
{
   var _local1 = this;
   _local1.DelayCount = _local1.DelayCount + 1;
   if(35 < _local1.DelayCount)
   {
      _root.attachMovie("Level1","Level10",1);
      _local1.Destroy(); // remove this
   }
};

=> Also removing this allows platforms to be visible.

luigismansion_edit.zip

[Toad06]

So I think I've finally found out what's wrong here: attachMovie() and removeMovieClip() are changing the value of this in Flash.

I've made two samples based on your original test:
test_this.zip

function A()
{
}
function B()
{
}
A.prototype = new MovieClip();
Object.registerClass("A",A);
A.prototype.onEnterFrame = function()
{
   trace(this + " - " + typeof this);
   _root.attachMovie("B","B0",1);
   trace(this + " - " + typeof this);
   this.removeMovieClip();
   trace(this + " - " + typeof this);
};
B.prototype = new MovieClip();
Object.registerClass("B",B);
attachMovie("A","A0",1); // depth is 2 in test_differentdepth.swf

---

test_samedepth.swf

Flash traces:

_level0.A0 - movieclip
 - movieclip
 - movieclip

Ruffle traces:

_level0.A0 - movieclip
_level0.A0 - movieclip
_level0.A0 - movieclip

---

test_differentdepth.swf

Flash traces:

_level0.A0 - movieclip
_level0.A0 - movieclip
 - movieclip

Ruffle traces:

_level0.A0 - movieclip
_level0.A0 - movieclip
_level0.A0 - movieclip

---

Note that replacing all instances of this in the samples with _level0.A0 produces consistent results in Flash and Ruffle.

Trace in test_samedepth.swf

_level0.A0 - movieclip
undefined - undefined
undefined - undefined

Trace in test_differentdepth.swf

_level0.A0 - movieclip
_level0.A0 - movieclip
undefined - undefined

[Herschel]

Sounds like another case of #993 -- after a clip is removed/overwritten, the object should go into a "removed" state and return undefined for all properties, and "" when coerced to a string.