builtin/item.lua: callbacks with copies of positions and nodes rather than recycle the same ones, which callbacks can modify

builtin/item.lua

@@ -124,7 +124,10 @@ end
 function minetest.item_place_node(itemstack, placer, pointed_thing)
 	local item = itemstack:peek_item()
 	local def = itemstack:get_definition()
-	if def.type == "node" and pointed_thing.type == "node" then
+	if def.type ~= "node" or pointed_thing.type ~= "node" then
+		return itemstack
+	end
+
 	local under = pointed_thing.under
 	local oldnode_under = minetest.env:get_node(under)
 	local olddef_under = ItemStack({name=oldnode_under.name}):get_definition()
@@ -183,17 +186,22 @@ function minetest.item_place_node(itemstack, placer, pointed_thing)
 
 	-- Run callback
 	if def.after_place_node then
-			def.after_place_node(place_to, placer)
+		-- Copy place_to because callback can modify it
+		local place_to_copy = {x=place_to.x, y=place_to.y, z=place_to.z}
+		def.after_place_node(place_to_copy, placer)
 	end
 
-		-- Run script hook (deprecated)
+	-- Run script hook
 	local _, callback
 	for _, callback in ipairs(minetest.registered_on_placenodes) do
-			callback(place_to, newnode, placer, oldnode)
+		-- Copy pos and node because callback can modify them
+		local place_to_copy = {x=place_to.x, y=place_to.y, z=place_to.z}
+		local newnode_copy = {name=newnode.name, param1=newnode.param1, param2=newnode.param2}
+		local oldnode_copy = {name=oldnode.name, param1=oldnode.param1, param2=oldnode.param2}
+		callback(place_to_copy, newnode_copy, placer, oldnode_copy)
 	end
 
 	itemstack:take_item()
-	end
 	return itemstack
 end
 
@@ -243,9 +251,11 @@ function minetest.node_punch(pos, node, puncher)
 	-- Run script hook
 	local _, callback
 	for _, callback in ipairs(minetest.registered_on_punchnodes) do
-		callback(pos, node, puncher)
+		-- Copy pos and node because callback can modify them
+		local pos_copy = {x=pos.x, y=pos.y, z=pos.z}
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		callback(pos_copy, node_copy, puncher)
 	end
-
 end
 
 function minetest.node_dig(pos, node, digger)
@@ -268,8 +278,8 @@ function minetest.node_dig(pos, node, digger)
 		local drops = minetest.get_node_drops(node.name, wielded:get_name())
 
 		-- Wear out tool
-		tp = wielded:get_tool_capabilities()
-		dp = minetest.get_dig_params(def.groups, tp)
+		local tp = wielded:get_tool_capabilities()
+		local dp = minetest.get_dig_params(def.groups, tp)
 		wielded:add_wear(dp.wear)
 		digger:set_wielded_item(wielded)
 
@@ -282,10 +292,8 @@ function minetest.node_dig(pos, node, digger)
 		end
 	end
 	
-	local oldnode = nil
 	local oldmetadata = nil
 	if def.after_dig_node then
-		oldnode = node;
 		oldmetadata = minetest.env:get_meta(pos):to_table()
 	end
 
@@ -294,13 +302,19 @@ function minetest.node_dig(pos, node, digger)
 	
 	-- Run callback
 	if def.after_dig_node then
-		def.after_dig_node(pos, oldnode, oldmetadata, digger)
+		-- Copy pos and node because callback can modify them
+		local pos_copy = {x=pos.x, y=pos.y, z=pos.z}
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		def.after_dig_node(pos_copy, node_copy, oldmetadata, digger)
 	end
 
-	-- Run script hook (deprecated)
+	-- Run script hook
 	local _, callback
 	for _, callback in ipairs(minetest.registered_on_dignodes) do
-		callback(pos, node, digger)
+		-- Copy pos and node because callback can modify them
+		local pos_copy = {x=pos.x, y=pos.y, z=pos.z}
+		local node_copy = {name=node.name, param1=node.param1, param2=node.param2}
+		callback(pos_copy, node_copy, digger)
 	end
 end