string length issue

[Dawn]

I'm using tags for my oUF layout that abbreviate long names.

	local oldName = UnitName(unit)
	local newName = (string.len(oldName) > 14) and string.gsub(oldName, "%s?(.[\128-\191]*)%S+%s", "%1. ") or oldName
	
	if not UnitIsPlayer(unit) then
		return utf8sub(newName, 14, false)
	else
		return oldName
	end

Everything works fine, but on level up the following error can occur. It only seems to happen when the unit name contains letters like "Æ", "Ø" and the like.

(Line 47 is highlighted red, above.)

Message: Interface\AddOns\oUF_Slim\Slim_Tags.lua:47: bad argument #1 to 'len' (string expected, got nil)
Time: 11/18/10 18:43:03
Count: 1
Stack: [C]: in function `len'
Interface\AddOns\oUF_Slim\Slim_Tags.lua:47: in function `func'
Interface\AddOns\oUF\elements\tags.lua:595: in function `UpdateTag'
Interface\AddOns\oUF\elements\tags.lua:375: in function <Interface\AddOns\oUF\elements\tags.lua:370>

Locals: (*temporary) = nil
(*temporary) = "string expected, got nil"

What I do not get is why it happens on level up. Normally, you can switch through units with no matter what characters and the name always abbreviates/updates correctly.

Any idea how to fix it or maybe a workaround?

[yj589794]

hmmm, seems a bit odd.

What events is your tag registered to update from?

It may be that one of the events is being triggered without a parameter in the case that the player levels up.

[Ailae]

I suppose you could check that oldName isn't nil before trying to something with it. That'll probably stop the error, but doesn't really solve it. Can you "force" the event and add some printouts maybe?

[Dawn]

Originally Posted by yj589794 What events is your tag registered to update from?

It's simply "UNIT_NAME_UPDATE"

Originally Posted by Ailae I suppose you could check that oldName isn't nil before trying to something with it. That'll probably stop the error, but doesn't really solve it. Can you "force" the event and add some printouts maybe?

How do I check if it isn't nil? What exactly do you mean with "force the event"? I mean switching targets = "UNIT_NAME_UPDATE", but like I said that works.


Btw, this is what I use for utf8sub, pretty straight forward, maybe except for the additional length check.

local utf8sub = function(string, i, dots)
	local bytes = string:len()
	if (bytes <= i) then
		return string
	else
		local len, pos = 0, 1
		while(pos <= bytes) do
			len = len + 1
			local c = string:byte(pos)
			if c > 240 then
				pos = pos + 4
			elseif c > 225 then
				pos = pos + 3
			elseif c > 192 then
				pos = pos + 2
			else
				pos = pos + 1
			end
			if (len == i) then break end
		end

		if (len == i and pos <= bytes) then
			return string:sub(1, pos - 1)..(dots and "..." or "")
		else
			return string
		end
	end
end

Edit:
"I do believe this is related to UTF8 and those special characters messing up the abbreviation."

I just tripple tested it and it doesn't matter if the player or player pet name contains special characters. It just happens.

[Ailae]

To check if it's not nil you can just do

if oldName then dostuff() end

What I meant by forcing the event was if you could tell oUF that the event for when a player levels happened when it actually didn't, since that's when the issue seems to crop up.

[Xubera]

to force the event, you just mimic it

so like if your eventhandler is called event handler, you just manually run the function... i.e

function eventHandler(frame, event, ...)
  --do Stuff
end

and then in the in-game chat box, just type

/run eventHandler(myFrame, "UNIT_NAME_UPDATE", arg1)

where arg1 is what normally gets passed with the event. also, to call the function it needs to be global, so you can take away the local, and when you fix the issue, just add local back in its place

[Dawn]

Figured it out. I was using

self:Tag(self.Name, '[afkdnd][difficulty][smartlevel]  [raidcolor][abbrevname]')

which seemed to confuse the string:len() check. And that's also where the damn level came from, which obviously had nothing to do with the utf8sub function or the abbreviation tag itself.

Worked like a charm again, after splitting it up into 2 separate font strings. D'OH!

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