Big speedup

Using a single call to get an iterator using getAllStacks
instead of doing a call for each slot individually

craft.lua

@@ -85,17 +85,21 @@ end
 ---@return table|nil
 local function read_chest_contents()
     local contents = {}
-    local size = inventory.getInventorySize(sides.forward)
-    if not size then
-        return nil
+
+    local iter = inventory.getAllStacks(sides.forward)
+    if not iter then
+        return nil -- not facing an inventory
     end
-    for slot = 1, size do
-        local stack = inventory.getStackInSlot(sides.forward, slot)
-        if stack then
+
+    local stack = iter()
+    while stack do
+        if stack.name then -- check if the slot has an item in it
             local name = stack.name .. ";" .. stack.damage
             add(contents, name, stack.size)
         end
+        stack = iter()
     end
+
     return contents
 end
 
@@ -105,11 +109,12 @@ local function store_item()
     -- check if that item is present in the inventory
     local item = inventory.getStackInInternalSlot()
 
-    local size = inventory.getInventorySize(sides.forward)
+    local iter = inventory.getAllStacks(sides.forward)
+    local slot = 1
     local empty_slot = -1
-    for slot = 1, size do
-        local stack = inventory.getStackInSlot(sides.forward, slot)
-        if stack then
+    local stack = iter()
+    while stack do
+        if stack.name then
             if stack.name == item.name then
                 inventory.dropIntoSlot(sides.forward, slot)
                 -- check if all items have been stored
@@ -124,6 +129,8 @@ local function store_item()
                 empty_slot = slot
             end
         end
+        stack = iter()
+        slot = slot + 1
     end
 
     -- item not present in inventory
@@ -157,20 +164,23 @@ local function fetch_item(item, output_slot, count)
 
     local name, damage = parse_item(item, ";")
     robot.select(output_slot)
-    local size = inventory.getInventorySize(sides.forward)
-    if not size then
+    local iter = inventory.getAllStacks(sides.forward)
+    if not iter then
         print('Not facing a chest')
         return false
     end
 
-    for slot = 1, size do
-        local stack = inventory.getStackInSlot(sides.forward, slot)
-        if stack then
+    local stack = iter()
+    local slot = 1
+    while stack do
+        if stack.name then
             if stack.name == name and stack.damage == damage then
                 inventory.suckFromSlot(sides.forward, slot, count)
                 return true
             end
         end
+        stack = iter()
+        slot = slot + 1
     end
 
     print('Missing ' .. item)