The Great Restubbening - part 1

[Dinnerbone]

We currently have a bunch of ways to stub things:

• Have a comment saying stub, return Undefined
• Have a (warning or error or info) saying (stub or not implemented), return Undefined
• Return an error saying stub

This changes all rust stubs within AVM1 & AVM2 classes to a new stub system, which we should use going forwards. It prints a warning when the first time an individual stub is encountered, and keeps track of the stubs encountered for a movie. It also changes things that previously errored, to return Undefined.

Later PRs will aim to achieve:

• A way to list all stubs encountered during a movie, maybe in crash reports or its own menu?
• A way to list all stubs that Ruffle has, in a format of our choosing (maybe make github issues for remaining stubs?)
• Converting AS stubs to use the same system

Individual PRs so as not to do a "change the world" PR, and we can benefit from the system right away.

[Aaron1011]

It looks like linkme doesn't support WASM: dtolnay/linkme#6

[Dinnerbone]

The feature isn't enabled on web (or anywhere by default) - it'll be used by a tool that just extracts the list and dumps it out

[Lord-McSweeney]

Can you also implement a native function in ActionScript (probably in the __ruffle__ namespace) to warn about a stub? There are a couple stubs written in ActionScript, including Loader.unload.

[Lord-McSweeney]

Also, shouldn't set_tab_children return Value::Undefined instead of true?

[Dinnerbone]

Can you also implement a native function in ActionScript (probably in the __ruffle__ namespace) to warn about a stub? There are a couple stubs written in ActionScript, including Loader.unload.

That's what I meant by:

Later PRs will aim to achieve:

• Converting AS stubs to use the same system

[Lord-McSweeney]

Ok, thanks! I also noticed that the PR returns undefined in places that previously errored, but functions using these will probably expect a different type. Here are all the incorrect types I could find:

DisplayObjectContainer.areInaccessibleObjectsUnderPoint should return a boolean (should probably return False in this case)
DisplayObjectContainer.getObjectsUnderPoint should return an array
SoundMixer.areSoundsInaccessible should return a boolean (should probably return False in this case)
Font.enumerateFonts should return an array
StaticText.text should return a string (empty string in this case)
Proxy.isAttribute should return a boolean (I have no idea whether to return true or false here)

[Bale001]

For stubbing AS3 methods, I think using metadata tags would look nice, like this:

[Ruffle(Stub)]
public function registerClassAlias(a:String, b:Object):void {}

[Dinnerbone]

For stubbing AS3 methods, I think using metadata tags would look nice, like this:

[Ruffle(Stub)]
public function registerClassAlias(a:String, b:Object):void {}

I have no idea how to get that working, but I'll give it a shot! My plan was just to call __ruffle__.stubMethod etc

[Dinnerbone]

Ok, thanks! I also noticed that the PR returns undefined in places that previously errored, but functions using these will probably expect a different type. Here are all the incorrect types I could find:

DisplayObjectContainer.areInaccessibleObjectsUnderPoint should return a boolean (should probably return False in this case) DisplayObjectContainer.getObjectsUnderPoint should return an array SoundMixer.areSoundsInaccessible should return a boolean (should probably return False in this case) Font.enumerateFonts should return an array StaticText.text should return a string (empty string in this case) Proxy.isAttribute should return a boolean (I have no idea whether to return true or false here)

Fixed!

[Lord-McSweeney]

It appears that we are stubbing undocumented methods (such as getMaxSize and getDiskUsage) in AVM1's SharedObject (at least, according to https://open-flash.github.io/mirrors/as2-language-reference/index.html). Could we add comments indicating that they are undocumented methods?

[Dinnerbone]

It appears that we are stubbing undocumented methods (such as getMaxSize and getDiskUsage) in AVM1's SharedObject (at least, according to https://open-flash.github.io/mirrors/as2-language-reference/index.html). Could we add comments indicating that they are undocumented methods?

There's a lot of conflicting documentation for AS1 & AS2, and we implement a whole bunch of stuff that's not well documented.
This PR doesn't change what's stubbed, only how they're stubbed, so can we leave this for a future PR or open an issue? There's a lot of stuff that it could affect but it's not the scope of this PR to address them.