Bug or feature?

[Spychotic]

Question;

I have just experienced a confusing issue where an assembler making satellites using resources imported to a requester chest then loaded using an inserter would get "jammed".

The assembler's output was not blocked, and it was missing inputs, yet the inserter was static.

Careful inspection revealed the problem; the inserter had a handful of goods - specifically, the accumulators which were missing from the assembler's required resources - but they weren't loading. The inserter was simply holding them over the assembler, as if the input slot was blocked.

And the cause - well, the apparent cause - was also quickly revealed; it turns out that the accumulators the insert is holding all have ~70% hit points. With these defective goods removed, everything works fine again.

There's some more accus with missing HP in the chest, and when the inserter grabs them and tries to load them into the assembler.... again everything stops and we're back to how we were before. Again, clearing the damaged goods from the inserter clears the problem.

Is this a bug, or a really, really, REALLY annoying feature?

Regards,

Spike

[Loewchen]

Feature, you need to repair them to be able to stack them.

[TruePikachu]

There are three kinds of items. The general rule is:

• If the item is strictly an intermediate product (e.g. electronic circuits), the item won't get damaged anyway and so stacking works "as expected".
• If the item is used as a fractionally-consumable resource (e.g. science packs, repair packs, and ammo), damaged items will "stack" such that they will combine into as many full-health items as possible and a single damaged item with the remaining health (e.g. three 90%-health science packs will stack into two 100%-health and one 70%-health).
• If the item is used to construct an entity (e.g. accumulators):
  • Damaged items won't stack with undamaged items.
  • Undamaged items stack together "as expected".
  • Damaged items average out their damage across all items in the stack (e.g. a 20%-health turret stacked with a 85% and a 90% will make a stack of three 65%-health turrets, since 20%+85%+90%=195% and 195%÷3=65%).