Use nil instead of -1 for default enchantment charge

apps/openmw/mwlua/types/item.cpp

@@ -1,5 +1,6 @@
 #include <sol/sol.hpp>
 
+#include "../../mwmechanics/spellutil.hpp"
 #include "../../mwworld/class.hpp"
 
 #include "../itemdata.hpp"
@@ -10,10 +11,16 @@ namespace MWLua
 {
     void addItemBindings(sol::table item, const Context& context)
     {
-        item["getEnchantmentCharge"]
+        item["getEnchantmentCharge"] = [](const Object& object) -> sol::optional<float> {
-            = [](const Object& object) { return object.ptr().getCellRef().getEnchantmentCharge(); };
+            float charge = object.ptr().getCellRef().getEnchantmentCharge();
-        item["setEnchantmentCharge"]
+            if (charge == -1)
-            = [](const GObject& object, float charge) { object.ptr().getCellRef().setEnchantmentCharge(charge); };
+                return sol::nullopt;
+            else
+                return charge;
+        };
+        item["setEnchantmentCharge"] = [](const GObject& object, sol::optional<float> charge) {
+            object.ptr().getCellRef().setEnchantmentCharge(charge.value_or(-1));
+        };
         item["isRestocking"]
             = [](const Object& object) -> bool { return object.ptr().getCellRef().getCount(false) < 0; };
 

files/lua_api/openmw/types.lua

@@ -652,7 +652,7 @@
 -- Get this item's current enchantment charge.
 -- @function [parent=#Item] getEnchantmentCharge
 -- @param openmw.core#GameObject item
--- @return #number The charge remaining. -1 if the enchantment has never been used, implying the charge is full. Unenchanted items will always return a value of -1.
+-- @return #number The charge remaining. `nil` if the enchantment has never been used, implying the charge is full. Unenchanted items will always return a value of `nil`.
 
 ---
 -- Checks if the item restocks.
@@ -665,7 +665,7 @@
 -- Set this item's enchantment charge.
 -- @function [parent=#Item] setEnchantmentCharge
 -- @param openmw.core#GameObject item
--- @param #number charge
+-- @param #number charge Can be `nil` to reset the unused state / full
 
 ---
 -- Whether the object is supposed to be carriable. It is true for all items except