Error handler: own function with the error-site stack, stop replacing the global error

api/api.lua

@@ -1494,13 +1494,10 @@ end
 -- return object
 function pfUI.api.GetNoNameObject(frame, objtype, layer, arg1, arg2)
   -- A nil/non-frame parent otherwise dies on frame:GetRegions()/:GetChildren()
-  -- below, and the traceback stops here — useless, since all callers share this
-  -- line. pfUI shadows Lua's `error` (dropping the level arg and not throwing),
-  -- so fold the caller frame in via debugstack to name the offending skin, then
-  -- bail so we don't fall through and crash on frame:GetRegions() anyway.
+  -- below, where the message would name this line, shared by every caller;
+  -- level 2 names the offending skin instead.
   if type(frame) ~= "table" or not frame.GetRegions then
-    error("GetNoNameObject: invalid parent frame\n" .. debugstack(2, 3, 0))
-    return
+    error("GetNoNameObject: invalid parent frame", 2)
   end
 
   local arg1 = arg1 and gsub(arg1, "([%+%-%*%(%)%?%[%]%^])", "%%%1")

pfUI.lua

@@ -461,15 +461,20 @@ message = function(msg)
 end
 print = print or message
 
-error = function(msg)
-  if PF_DEBUG_MODE then message(debugstack()) end
-  if string.find(msg, "AddOns\\pfUI") then
-    DEFAULT_CHAT_FRAME:AddMessage("|cffcc3333ERROR: |cffff5555".. (msg or "nil" ))
-  elseif not pfUI_config or (pfUI_config.global and pfUI_config.global.errors == "1") then
-    DEFAULT_CHAT_FRAME:AddMessage("|cffcc3333ERROR: |cffff5555".. (msg or "nil" ))
+-- Errors print to chat: pfUI's own always, other addons' when the errors
+-- option is on. In debug mode the stack follows, starting at the code that
+-- raised the error rather than at this handler.
+seterrorhandler(function(msg)
+  msg = tostring(msg)
+  if PF_DEBUG_MODE then
+    local height = GetErrorCallstackHeight()
+    message(height and debugstack(GetCallstackHeight() - height + 1) or debugstack(2))
   end
-end
-seterrorhandler(error)
+  if string.find(msg, "AddOns\\pfUI") or not pfUI_config
+  or (pfUI_config.global and pfUI_config.global.errors == "1") then
+    DEFAULT_CHAT_FRAME:AddMessage("|cffcc3333ERROR: |cffff5555" .. msg)
+  end
+end)
 
 function pfUI.SetupCVars()
   ClearTutorials()