[MC-5413] Items with NBT data do not stack correctly due to serialization

Items in inventory do not stack consistently depending on if they were created before or after when you last logged out or did a Save and Quit.

Steps to reproduce:
1. Name a block of dirt "A" using the anvil.
2. Name another block of dirt "A" and see that it does stack with the first.
3. Save and Quit then open the world again.
4. Name a third block of dirt "A" and see that it does NOT stack with the first two.
5. Save and Quit then open the world yet again.
6. See that now all three blocks of dirt stack together correctly.

Linked issues

is duplicated by

MC-4282 Items named with the same names separately in an anvil doesn't stack

MC-9419 Renamed Items dont stack if they fall in a hopper.

MC-14913 Anvil Renamed Items Won't Stack

relates to

MC-335 Dropped items with NBT tags do not stack

Comments

Tails 2012-12-27T17:46:20Z

Confirmed.

Dean Baset 2012-12-28T13:17:03Z

Confirmed

Jesper the End 2013-02-11T14:57:56Z

I can confirm this bug for 13w06a. It's really annoying for item sorters. I also noticed the NBT data is just the same.

Abandoned account 2013-02-11T16:46:54Z

Confirmed and voted.

Jesper the End 2013-02-17T11:39:52Z

for some reason, it does work after a while, I'm not sure when, but I sucked an item up in a hopper then dropped it again using a dropper, then they did stack.

Jesper the End 2013-02-17T11:50:46Z

Confirmed for 13w07a btw

Jesper the End 2013-02-26T17:51:06Z

confirmed for 13w09a

Jesper the End 2013-09-08T09:57:41Z

this bug sort of exists again in 13w36b using the /give command: [MC-30468]

Sebastian Schieß 2016-03-26T17:59:11Z

It "reproduce" some times on multiplayer servers.

Lucas Elliott 2017-08-30T13:49:37Z

I am still experiencing this bug in 1.12 on play.wildcraftmc.com

violine1101 2017-08-30T14:11:44Z

It works fine for me. I assume it's only an issue because of modified server software (e.g. Bukkit/Spigot).