MC-249697Spawn eggs set to spawn certain entities lose their name when upgraded to 1.13+
Relates to MC-124065
The bug
When spawn eggs set to spawn entities which aren't any of the standard set (available in the Creative inventory in 17w46a and prior, and with their own IDs in 17w47a onwards) are upgraded to a modern version such as 1.18.2, they are set to pig spawn eggs. The name of the pig spawn egg overwrites the name the spawn egg used in previous versions, making it impossible to tell what the egg spawns in-game without using it.
How to reproduce
- Obtain a nonstandard spawn egg via one of the two commands below in a pre-1.13 version
- Take note of the spawn egg's name
- Upgrade the world with this spawn egg to the latest version
- Take note of the spawn egg's name
Example commands
- 1.3.1 to 1.8.9 ender dragon spawn egg:
/give @p spawn_egg 1 63
- 1.12.2 wither spawn egg:
/give @s spawn_egg 1 0 {EntityTag:{id:"minecraft:wither"}}
Expected results
The spawn egg's name would be retained in some form as to make it clear what entity the item spawns.
Actual results
The item takes on the name of "Pig Spawn Egg", making it impossible to tell what it actually spawns.
How to fix
When upgrading spawn eggs, the game should check what entity ID is assigned to it. If it doesn't match one of the spawn eggs in 1.13+ with dedicated item IDs, then it should be given a custom name consisting of the entity's display name followed by " Spawn Egg".
Created Issue:
Spawn eggs set to spawn certain entities lose their name when upgraded to 1.13+
Relates to
MC-124065The bug
When spawn eggs set to spawn entities which aren't any of the standard set (available in the Creative inventory in 17w46a and prior, and with their own IDs in 17w47a onwards) are upgraded to a modern version such as 1.18.2, they are set to pig spawn eggs. The name of the pig spawn egg overwrites the name the spawn egg used in previous versions, making it impossible to tell what the egg spawns in-game without using it.
How to reproduce
- Obtain a nonstandard spawn egg via one of the two commands below in a pre-1.13 version
- Take note of the spawn egg's name
- Upgrade the world with this spawn egg to the latest version
- Take note of the spawn egg's name
Example commands
- 1.3.1 to 1.8.9 ender dragon spawn egg:
/give @p spawn_egg 1 63- 1.12.2 wither spawn egg:
/give @s spawn_egg 1 0 {EntityTag:{id:"minecraft:wither"}}Expected results
The spawn egg's name would be retained in some form as to make it clear what entity the item spawns.
Actual results
The item takes on the name of "Pig Spawn Egg", making it impossible to tell what it actually spawns.
How to fix
When upgrading spawn eggs, the game should check what entity ID is assigned to it. If it doesn't match one of the spawn eggs in 1.13+ with dedicated item IDs, then it should be given a custom name consisting of the entity's display name followed by " Spawn Egg".
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The bug
From 11w49a (1.1) to 17w46a, spawn eggs existed for the snow golem, iron golem, ender dragon and wither. 17w47a (1.13) changed spawn eggs so that each egg is its own namespaced ID, rather than one centralized item ID (spawn_egg) with its target entity specified via NBT. As such, upgrading a world containing a spawn egg from a pre-1.13 world into a world in 1.13 or a newer version will convert it into its corresponding spawn egg item ID if a matching one is found. Spawn eggs for other entities are instead changed into pig spawn eggs with NBT that preserves the initially spawned mob (see also MC-124065).
22w44a re-introduces proper spawn eggs for the wither, ender dragon, iron golem and snow golem. As these spawn eggs existed prior to 1.13, it'd be expected that worlds containing them would have them upgrade to these new spawn egg types, but they do not.
How to reproduce
A 1.12.2 world containing a snow golem spawn egg, iron golem spawn egg, wither spawn egg and ender dragon spawn egg in a chest directly in front of the player is attached.
- Download the attached world
- Open this world in version 1.12.2
- Mouse over the four gray spawn eggs, confirming the entity that they spawn (you can also give yourself a spawner and use the eggs on this spawner to confirm they do indeed contain the mob in question)
- Open the world in snapshot 22w44a or (if this isn't fixed immediately, which hopefully isn't the case) a later version
- Check on the four spawn eggs
- Use each one to confirm its identity
Expected results
The four spawn eggs from 1.12.2 would be converted to their 22w44a+ counterparts accordingly.
Actual results
These four spawn eggs instead become pig spawn eggs with extra NBT.
How to fix
A data fixer should be implemented that points these four old spawn eggs towards the new alphanumeric IDs so they convert in the exact same way as all other pre-1.13 spawn eggs.
Further notes
The NBT on these pig spawn eggs mean that they function identically to the 22w44a spawn eggs, but are very hard to distinguish from each other without directly using them (MC-249697), which for the ender dragon and wither spawn eggs is VERY dangerous.
The suggested fix won't really work without adding a string only used for upgraded items though. Additionally, this is how the eggs work in current versions, no different name unless display name is provided, so it is, in a way, synchronized with new versions.
I, personally, would resolve this as Won't Fix for those reasons.