Versions used

Minecraft 1.16.5
Forge 36.2.22
PrettyPipes-1.9.5.jar

Description and how to replicate

Pretty Pipes appears to fail to properly calculate how many of an item it can craft when a recipe outputs multiple of an item.
This results in Pretty Pipes believing it can craft more items than it actually can (often leaving stuck crafts on the terminal or junk leftovers in the crafting module inventory)

Small pretty pipes system to replicate this issue:

When the crafting card is set to (for the sake of an example) 1 andesite -> 1 cobble, and there's 20 andesite in the system.

Ask for the highest amount of cobble you can. It knows to only ask for 20 cobblestone, as expected.

When the crafting card is set to 1 andesite -> 2 cobble (still with 20 andesite in the system)

Ask for the highest amount of cobble you can.

The pretty pipes system promises to send back 80 cobblestone, rather than the expected 40 (since there's 20 andesite in the system and every andesite can be turned into two cobble, according to the crafting card)

Another example would be setting the recipe to 1 andesite -> 5 cobble, with 20 andesite in the system. It promises 384 (max amount) rather than the expected 100.

The issue took place in singleplayer.

Though it has been originally reported within a modpack ( EnigmaticaModpacks/Enigmatica6#3892 ) I have reproduced it using a minimal instance containing just the mods described above