Attempt to find 'this' in non-framescript object?

[Coote]

I'm getting a really funky error with ncHoverBind when attempting to use it with a particular compilation (already notified the person who made it), and wondering if the compatibility issue is with ncHoverBind, or possibly theirs.

I'm well aware that 'this' was removed as a global variable a while back, and ncHoverBind doesn't even use 'this' to begin with.

Here's the error...

Message: Interface\AddOns\ncHoverBind\ncHoverBind.lua:247: Attempt to find 'this' in non-framescript object
Time: 11/11/12 23:01:33
Count: 4
Stack: [C]: in function `GetObjectType'
Interface\AddOns\ncHoverBind\ncHoverBind.lua:247: in function `register'
Interface\AddOns\ncHoverBind\ncHoverBind.lua:261: in function `?'
Interface\FrameXML\ChatFrame.lua:4358: in function `ChatEdit_ParseText'
Interface\FrameXML\ChatFrame.lua:4052: in function `ChatEdit_SendText'
Interface\FrameXML\ChatFrame.lua:4091: in function `ChatEdit_OnEnterPressed'
[string "*:OnEnterPressed"]:1: in function <[string "*:OnEnterPressed"]:1>

Locals: (*temporary) = <table> {
 1 = <unnamed> {
 }
 2 = <unnamed> {
 }
 3 = <unnamed> {
 }
 4 = <unnamed> {
 }
 0 = <unnamed> {
 }
}

Here's the code blocks containing lines 247 and 260.

(246-257)

		local function register(val)
			if val.IsProtected and val.GetObjectType and val.GetScript and val:GetObjectType()=="CheckButton" and val:IsProtected() then
				local script = val:GetScript("OnClick")
				if script==button then
					val:HookScript("OnEnter", function(self) bind:Update(self) end)
				elseif script==stance then
					val:HookScript("OnEnter", function(self) bind:Update(self, "STANCE") end)
				elseif script==pet then
					val:HookScript("OnEnter", function(self) bind:Update(self, "PET") end)
				end
			end
		end

(259-263)

		local val = EnumerateFrames()
		while val do
			register(val)
			val = EnumerateFrames(val)
		end

[Phanx]

That error is caused by non-frame tables whose metatable __index is a frame. You can fix it by making your frame check more robust:

if val.IsProtected 
and val.GetObjectType 
and val.GetScript 
and type(rawget(val, 0)) == "userdata"
and val:GetObjectType() == "CheckButton" 
and val:IsProtected() then

[Coote]

Thanks for that, but still a no go. It just throws an error at the second code snippet I pasted in above.

Message: Interface\AddOns\ncHoverBind\ncHoverBind.lua:262: EnumerateFrames: Couldn't find 'this' in current object
Time: 11/12/12 00:49:02
Count: 1
Stack: [C]: in function `EnumerateFrames'
Interface\AddOns\ncHoverBind\ncHoverBind.lua:262: in function `?'
Interface\FrameXML\ChatFrame.lua:4358: in function `ChatEdit_ParseText'
Interface\FrameXML\ChatFrame.lua:4052: in function `ChatEdit_SendText'
Interface\FrameXML\ChatFrame.lua:4091: in function `ChatEdit_OnEnterPressed'
[string "*:OnEnterPressed"]:1: in function <[string "*:OnEnterPressed"]:1>

Locals: (*temporary) = <table> {
 1 = <unnamed> {
 }
 2 = <unnamed> {
 }
 3 = <unnamed> {
 }
 4 = <unnamed> {
 }
 0 = <unnamed> {
 }
}

If it helps any, this error only pops its ugly head with SnailUI. ncHoverBind plays nicely with everything else I've tested it with since MOP released.

[Phanx]

You need to also make sure you don't pass non-frame values back into EnumerateFrames. This is probably the easiest way to do it:

		local function register(val)
			if val.IsProtected and val.GetObjectType and val.GetScript and type(rawget(val, 0)) == "userdata" and val:GetObjectType()=="CheckButton" and val:IsProtected() then
				local script = val:GetScript("OnClick")
				if script==button then
					val:HookScript("OnEnter", function(self) bind:Update(self) end)
				elseif script==stance then
					val:HookScript("OnEnter", function(self) bind:Update(self, "STANCE") end)
				elseif script==pet then
					val:HookScript("OnEnter", function(self) bind:Update(self, "PET") end)
				end
				return true
			end
		end

		local val = EnumerateFrames()
		while val do
			if register(val) then
				val = EnumerateFrames(val)
			end
		end

[Coote]

Even worse yet. Those changes cause the game client to crash.

[SDPhantom]

Originally Posted by Phanx local val = EnumerateFrames() while val do if register(val) then val = EnumerateFrames(val) end end

If register(val) ever returns false or nil, this will send the game into an infinite loop.



Try this with Phanx's other modification to register():

	local val = EnumerateFrames()
	while val and register(val) do
		val = EnumerateFrames(val)
	end

The only problem with this is when it runs into the error, it'll stop hooking. There isn't any other way around this.

[Dridzt]

You just made friends with Blizzard's broken taintLog tracking, say "hi"

/console taintLog 0 and see if the error disappears.

Edit: If you verify that the broken taint log mechanism is at fault you can workaround it by going through both your addons and finding any global frames that are unassigned local references and make sure they're assigned to a local variable.

[Coote]

That mostly works. No errors, and the binding confirmation pops up. Though, the issue now, after testing it, is binding no longer works with any of these changes.

I've reverted all these changes, and I guess I'll just use a different bar mod rather than trying to get it to play nicely with SnailUI for now.

[Phanx]

Well, the best solution to the problem would really be to figure out which addon is screwing with frame metatables and get its author to fix the problem.

[Coote]

Originally Posted by Phanx Well, the best solution to the problem would really be to figure out which addon is screwing with frame metatables and get its author to fix the problem.

I believe I've narrowed it down to the ActionBar module in SnailUI, and I've contacted the author. I posted this in the chance it may have been my addon, and in hopes there may have been a workaround on my end to get it working properly.

Thanks for the help, and even though it didn't amount to a whole lot in the end run, you guys still rock.