[BUG] /EsoUI/Ingame/Map/WorldMapFilters_Shared.lua:129: attempt to index a nil value

[renfrow]

This dialog pops up each time I move from one area to another (e.g. from world to delve). It started happening with the latest update (U35).

================= Stack Trace =================

/EsoUI/Ingame/Map/WorldMapFilters_Shared.lua:129: attempt to index a nil value
stack traceback:
/EsoUI/Ingame/Map/WorldMapFilters_Shared.lua:129: in function 'OnMapChanged'
|caaaaaa<Locals> mapFilterType = 0, mode = 2 </Locals>|r
/EsoUI/Libraries/Utility/ZO_CallbackObject.lua:132: in function 'ZO_CallbackObjectMixin:FireCallbacks'
|caaaaaa<Locals> self = [table:1]{fireCallbackDepth = 1}, eventName = "OnWorldMapChanged", registry = [table:2]{}, callbackInfoIndex = 8, callbackInfo = [table:3]{4 = F}, callback = /EsoUI/Ingame/Map/WorldMapFilters_Shared.lua:109, deleted = F </Locals>|r
user:/AddOns/TamrielMapping/TamrielMapping.lua:905: in function 'TTMP.CheckMapChange'
|caaaaaa<Locals> does_match = F </Locals>|r
user:/AddOns/TamrielMapping/TamrielMapping.lua:847: in function 'TTMP.OnUpdate'
|caaaaaa<Locals> iNowMillis = 447880 </Locals>|r
TamrielMapping_Update:3: in function '(main chunk)'
|caaaaaa<Locals> self = ud, time = 447.88000488281 </Locals>|r

================= Stack Trace =================

I added debug prints in TTMP.CheckMapChange:

-- ----------------------------------------------
-- Check if the map has changed and update the current player zone location
-- ----------------------------------------------
function TTMP.CheckMapChange()

	local does_match = DoesCurrentMapMatchMapForPlayerLocation()
	if not does_match then
		TTMP.is_viewing_map = ZO_WorldMap_DidPlayerChooseCurrentMap()
		if not TTMP.is_viewing_map then
			SetMapToPlayerLocation()
if TTMP_MENU_OPTIONS.ShowDebug then
  local mapFilterType = GetMapFilterType()
  if mapFilterType == MAP_FILTER_TYPE_STANDARD then
    dbgPrint("TTMP:CheckMapChange(): map filter type = ".."MAP_FILTER_TYPE_STANDARD")
  elseif mapFilterType == MAP_FILTER_TYPE_AVA_CYRODIIL then
    dbgPrint("TTMP:CheckMapChange(): map filter type = ".."MAP_FILTER_TYPE_AVA_CYRODIIL")
  elseif mapFilterType == MAP_FILTER_TYPE_AVA_IMPERIAL then
    dbgPrint("TTMP:CheckMapChange(): map filter type = ".."MAP_FILTER_TYPE_AVA_IMPERIAL")
  elseif mapFilterType == MAP_FILTER_TYPE_BATTLEGROUND then
    dbgPrint("TTMP:CheckMapChange(): map filter type = ".."MAP_FILTER_TYPE_BATTLEGROUND")
  else
    dbgPrint("TTMP:CheckMapChange(): unknown map filter type = "..mapFilterType)
  end
end
			CALLBACK_MANAGER:FireCallbacks("OnWorldMapChanged")
		end
	end

end

Looking at the stack trace "TamrielMapping.lua:905" is the FireCallbacks() above.

The debug prints out "MAP_FILTER_TYPE_STANDARD" (which has value 1) as the map filter type before we head into system code.

In the 4th line down of the stack trace you see that mapFilterType is 0 (unknown?) in OnMapChanged(). Here is the code for this routine (from https://esoapi.uesp.net/current/src/...hared.lua.html).

    local function OnMapChanged()
        local mapFilterType = GetMapFilterType()
        local mode = WORLD_MAP_MANAGER:GetMode()
        local newCurrentPanel
        if mapFilterType == MAP_FILTER_TYPE_STANDARD then
            newCurrentPanel = self.pvePanel
            self.pvePanel:SetMapMode(mode)
        elseif mapFilterType == MAP_FILTER_TYPE_AVA_CYRODIIL then
            newCurrentPanel = self.pvpPanel
            self.pvpPanel:SetMapMode(mode)
        elseif mapFilterType == MAP_FILTER_TYPE_AVA_IMPERIAL then
            newCurrentPanel = self.imperialPvPPanel
            self.imperialPvPPanel:SetMapMode(mode)
        elseif mapFilterType == MAP_FILTER_TYPE_BATTLEGROUND then
            newCurrentPanel = self.battlegroundPanel
            self.battlegroundPanel:SetMapMode(mode)
        end
        if self.currentPanel and self.currentPanel ~= newCurrentPanel then
            self.currentPanel:SetHidden(true)
        end
        newCurrentPanel:SetHidden(false)
        self.currentPanel = newCurrentPanel
    end

"newCurrentPanel:SetHidden(false)" is the code trying to index a nil value, meaning that newCurrentPanel is
nil. You'll notice that the if-then-elseif code has no fall through else clause, such that if 'mapFilterType' is not one of the mentioned values, it will remain nil.

Sooo... long question/discussion short, there needs to be an else clause, that sets the newCurrentPanel to a default value, and, they need to find out who is setting it to a bogus value (or clearing it, or not instantiating it).