Advancement trigger consume_item not working for single potion item stack

The bug

The advancement trigger consume_item is not working for single potion item stacks when consumed in Survival or Adventure mode.

How to reproduce

1. Download the attached data pack MC-120558 data pack.zip and place it in the datapacks folder of your world
2. Open the world and drink any potion in Survival mode
   → The advancement is not granted
3. Drink any potion in Creative mode
   → The advancement is granted as expected

Code analysis

Based on 1.12.2 decompiled using MCP 9.40

The method net.minecraft.item.ItemPotion.onItemUseFinish(ItemStack, World, EntityLivingBase) reduces the stack size before applying the potion effects and testing advancement triggers. Therefore when the triggers are tested 0*potion (acting like 0*air) is compared.

Reducing the stack size should probably happen right before the glass bottle is added to the inventory.