Adds 'consumable' field to BomItem model (#2890)

* Adds 'consumable' field to BomItem model

* Add consumable field to API

* Consumable items always count as "allocated" for a build

* Add new BOM fields to BOM item checksum calculation

* Display 'consumable' status in BOM table

* Fix order of database migrations

* Update unit tests

* Fix for BOM table

* Remove "infinite" field from StockItem model

- Not used anywhere for functionality
- Hidden from the user
- Now replaced by the "consumable" concept in the BuildOrder model

* Update build order allocation table display

* Prevent auto-allocation of stock to consumable BOM items

* Ignore consumable BOM items when allocating stock to a build order

* Reimplmement "footer" row for BOM table

* Fix "can_build" calculation

- Ignore "consumable" BOM items

* Unrelated typo fix

* Tweak BOM table

* More visual tweaks to BOM table

* Add unit test for consumable field

InvenTree/build/models.py

@@ -839,6 +839,10 @@ class Build(MPTTModel, ReferenceIndexingMixin):
         # Get a list of all 'untracked' BOM items
         for bom_item in self.untracked_bom_items:
 
+            if bom_item.consumable:
+                # Do not auto-allocate stock to consumable BOM items
+                continue
+
             variant_parts = bom_item.sub_part.get_descendants(include_self=False)
 
             unallocated_quantity = self.unallocated_quantity(bom_item)
@@ -972,7 +976,12 @@ class Build(MPTTModel, ReferenceIndexingMixin):
         return max(required - allocated, 0)
 
     def is_bom_item_allocated(self, bom_item, output=None):
-        """Test if the supplied BomItem has been fully allocated!"""
+        """Test if the supplied BomItem has been fully allocated"""
+
+        if bom_item.consumable:
+            # Consumable BOM items do not need to be allocated
+            return True
+
         return self.unallocated_quantity(bom_item, output) == 0
 
     def is_fully_allocated(self, output):

InvenTree/build/serializers.py

@@ -781,6 +781,10 @@ class BuildAllocationSerializer(serializers.Serializer):
                 quantity = item['quantity']
                 output = item.get('output', None)
 
+                # Ignore allocation for consumable BOM items
+                if bom_item.consumable:
+                    continue
+
                 try:
                     # Create a new BuildItem to allocate stock
                     BuildItem.objects.create(