Remove increment rune name to item name (#220)

Item name was being replaced by rune name in "register" function
Added the condition to only replace if the item name is empty, so that some system that checks the name of the pre-established item cannot be bugged

src/lua/functions/creatures/combat/spell_functions.cpp

@@ -129,32 +129,37 @@ int SpellFunctions::luaSpellRegister(lua_State* L) {
 	// spell:register()
 	Spell* spell = getUserdata<Spell>(L, 1);
 
-	if (spell) {
-		if (spell->spellType == SPELL_INSTANT) {
-			InstantSpell* instant = dynamic_cast<InstantSpell*>(getUserdata<Spell>(L, 1));
-			if (!instant->isScripted()) {
-				pushBoolean(L, false);
-				return 1;
-			}
-			pushBoolean(L, g_spells->registerInstantLuaEvent(instant));
-		} else if (spell->spellType == SPELL_RUNE) {
-			RuneSpell* rune = dynamic_cast<RuneSpell*>(getUserdata<Spell>(L, 1));
-			if (rune->getMagicLevel() != 0 || rune->getLevel() != 0) {
-				//Change information in the ItemType to get accurate description
-				ItemType& iType = Item::items.getItemType(rune->getRuneItemId());
+	if (!spell) {
+		reportErrorFunc(getErrorDesc(LUA_ERROR_SPELL_NOT_FOUND));
+		pushBoolean(L, false);
+		return 1;
+	}
+
+	if (spell->spellType == SPELL_INSTANT) {
+		InstantSpell* instant = dynamic_cast<InstantSpell*>(getUserdata<Spell>(L, 1));
+		if (!instant->isScripted()) {
+			pushBoolean(L, false);
+			return 1;
+		}
+		pushBoolean(L, g_spells->registerInstantLuaEvent(instant));
+	} else if (spell->spellType == SPELL_RUNE) {
+		RuneSpell* rune = dynamic_cast<RuneSpell*>(getUserdata<Spell>(L, 1));
+		if (rune->getMagicLevel() != 0 || rune->getLevel() != 0) {
+			// Change information in the ItemType to get accurate description
+			ItemType& iType = Item::items.getItemType(rune->getRuneItemId());
+			// If the item is not registered in items.xml then we will register it by rune name
+			if (iType.name.empty()) {
 				iType.name = rune->getName();
-				iType.runeMagLevel = rune->getMagicLevel();
-				iType.runeLevel = rune->getLevel();
-				iType.charges = rune->getCharges();
-			}
-			if (!rune->isScripted()) {
-				pushBoolean(L, false);
-				return 1;
 			}
-			pushBoolean(L, g_spells->registerRuneLuaEvent(rune));
+			iType.runeMagLevel = rune->getMagicLevel();
+			iType.runeLevel = rune->getLevel();
+			iType.charges = rune->getCharges();
 		}
-	} else {
-		lua_pushnil(L);
+		if (!rune->isScripted()) {
+			pushBoolean(L, false);
+			return 1;
+		}
+		pushBoolean(L, g_spells->registerRuneLuaEvent(rune));
 	}
 	return 1;
 }