Keep main inventory slots from armor equipment when restoring a character

The inventory bonus of equipment in the armor's grid (toolbelts) is
applied by the engine on the tick after the armor is inserted. The main
inventory was restored in the same tick, so the items of every slot past
80 plus research plus the armor's own bonus did not fit and were put in
a corpse: legendary mech armor with legendary toolbelts left 2125 of
2330 slots in the corpse.

The armor is now restored first, the character's inventory bonus is
raised to fit the saved main inventory, and the raise is removed again
on the next tick, or before an upload if the player leaves first.

Co-Authored-By: Claude Opus 5.5 (1M context) <noreply@anthropic.com>

plugins/player_sync/module/player_sync.lua

@@ -60,6 +60,19 @@ local function remove_player(player)
 	script_data.players[player.name] = nil
 end
 
+-- Remove the temporary inventory bonus a deserialized character got to fit its main inventory
+local function remove_inventory_bonus_raise(script_data, player_name)
+	local raises = script_data.inventory_bonus_raises
+	local raise = raises and raises[player_name]
+	if raise then
+		raises[player_name] = nil
+		local character = raise.character
+		if character.valid then
+			character.character_inventory_slots_bonus = character.character_inventory_slots_bonus - raise.bonus
+		end
+	end
+end
+
 
 player_sync = {}
 -- This function is called by instance.js as /sc player_sync.download_inventory("danielv", Escaped JSON string, package_number, total_packages_count) with data from the controller
@@ -73,6 +86,9 @@ end
 -- This function is called internally when a player leaves the game to
 -- serialize the player for upload.
 function player_sync.serialize_player(player, player_record)
+	-- Leaving on the tick of a download, the temporary bonus must not be uploaded
+	remove_inventory_bonus_raise(get_script_data(), player.name)
+
 	-- Editor mode is not supported.
 	if player.controller_type == defines.controllers.editor then
 		player.toggle_map_editor()
@@ -134,10 +150,17 @@ function player_sync.deserialize_player(player, finished_record)
 	-- Deserialize downloaded player data
 	local serialized_player = compat.json_to_table(finished_record.data)
 	assert(type(serialized_player) == "table", "wrong type for serialized_player")
-	local failed, spill =
+	local failed, spill, inventory_bonus_raise =
 		serialize.deserialize_player(player, serialized_player, finished_record.components, local_controller)
 	script_data.failed_deserialization[player.name] = failed
 	player_record.local_controller = nil
+	if inventory_bonus_raise and inventory_bonus_raise > 0 then
+		script_data.inventory_bonus_raises[player.name] = {
+			character = player.character,
+			bonus = inventory_bonus_raise,
+			tick = game.tick,
+		}
+	end
 
 	-- Restore player position and driving state
 	restore_position(player, finished_record)
@@ -396,6 +419,20 @@ player_sync.events[defines.events.on_player_joined_game] = function(event)
 	script_data.active_uploads[player.name] = nil
 end
 
+-- The inventory bonus of armor equipment applies on the tick after a download, the temporary bonus is no longer needed
+player_sync.events[defines.events.on_tick] = function(event)
+	local script_data = get_script_data()
+	local raises = script_data.inventory_bonus_raises
+	if not raises or next(raises) == nil then
+		return
+	end
+	for player_name, raise in pairs(raises) do
+		if raise.tick < event.tick then
+			remove_inventory_bonus_raise(script_data, player_name)
+		end
+	end
+end
+
 player_sync.on_nth_tick = {}
 player_sync.on_nth_tick[33] = function(event)
 	-- Periodically check players currently in the process of syncing