Opening a hopper inventory created by Server.createInventory will
currently have no effect as proper handling code is missing in
CraftEntityHuman for hopper inventories that aren't associated with a tile
entity or minecart. Initialization logic for hoppers is also missing from
CraftContainer, which is necessary for the opening of custom hopper
inventories.
This commit fixes the two aforementioned by adding proper handling to
CraftHumanEntity for opening inventories not associated with a tile
entity, and by adding initialization logic for hoppers to CraftContainer.
Previously fires spawned by lightning strikes were in the wrong locations.
This introduced the possibility of having blocks replaced when they should
not be.
EntityLightning now uses the correct locations as defined to spawn the
fires when needed.
When an entity is being moved as the passenger of an entity from one
entity to another, a VehicleExitEvent is fired, but it is assumed that the
current entity is a Vehicle. However, entities can be passengers of more than
just Vehicles, which causes a ClassCastException to be thrown.
This commit fixes the issue by checking that the current entity's vehicle's
bukkitEntity is an instance of Vehicle before casting it to Vehicle.
Prior to this change when a plugin called Player.hasLineOfSite() the
method would always return false because EntityHuman does not extend
EntityInsentient. This commit changes that by explicitly checking for
line of sight between two entities and returning that value.
Maven paths that include spaces (and possible other characters) get
improperly translated when using a file handle from a URL. This changes
the unit test to open a stream directly from the URL, providing proper
file resolution on multiple platforms.
This commit removes chat wrapping. It is no longer needed, as clients
properly render lines with line breaks.
This commit also changes an outgoing chat message to use the vanilla
behavior for indicating a client cannot chat with commands-only setting.
If a plugin generates an exception when returning a world generator, the
server will crash. This change adds a try-catch block to keep the server
from crashing on plugin defined world generators.
Custom inventories currently do not validate the titles provided. Null values
cause NPEs when writing packets. Values longer than 32 characters
disconnect clients.
This change throws and IllegalArgumentException for null titles or titles
longer than 32 characters.
The unleash event is only called for animals that are sitting - ones that
receive no movement vector. This adds the missing event call for
non-sitting animals.
When only considering trackers from player perspective, attach entity
packet could be sent before a packet for a respective vehicle is in view
and will, in turn, be ignored.
This adds another notification when the vehicle comes into view to cover
all cases.
A method has been added to Player which allows the server to send a sound string to the client. Assuming the client has the specified sound, it will be played. This is needed by the implementation of the /playsound command.
Items that cause entities to change state, including tags, chest, and
leashes, do not update the client properly following the firing of
PlayerInteractEntityEvent. This change makes the item checks occur
before the event fires, to concur with the client's assumptions.
This commit implements the ability to set the scale of hearts that the
client renders. When the Packet44UpdateAttributes packet is sent, the
max health attribute is replaced with a scaled version, to preserve the
scaled health illusion clientside.
In order to accurately display the scaled health for players, a true
health is stored within CraftPlayer, and the datawatcher now stores the
scaled health. The getHealth() method for players still returns their
true health.
Changed setHealth() within EntityLiving to appropriately handle health
for instances of EntityPlayer. Inlined a call to
setHealth(getMaxHealth()) within the EntityLiving constructor to work
around CraftEntity instantiation.
Additionally fixes the health values sent when eating food within
FoodMetaData and ItemFood, which previously sent the unscaled health;
this commit alters them to send the properly scaled health.
Additionally fixes BUKKIT-4535, BUKKIT-4536, and BUKKIT-4127
This changes livingEntity.addPotionEffect(PotionEffect, boolean) to
construct the MobEffect using the constructor that includes the ambient
setting as supplied by the PotionEffect
This also changes livingEntity.getActivePotionEffects() to construct the
PotionEffects using the ambient setting supplied by the MobEffects.
This change makes it so that EntityHuman#setPassengerOf(Entity) invokes
its parent method when leaving vehicles so that VehicleExitEvent is fired
for players leaving vehicles.
This change also fixes BUKKIT-2110, making it so VehicleExitEvent
correctly handles cancellation. The implementation of VehicleExitEvent
completely ignored the cancellation state of the event, making it so that
cancelling the event had no effect. Cancelling a VehicleExitEvent now
causes the entity to remain inside of the vehicle, with no visual stutter.
API has been added to interface with Horses and to modify their inventories. Horse entities will now be recognized with the type EntityType.HORSE, and will no longer be UNKNOWN.
HorseJumpEvent, EntityDamageEvent, and EntityTameEvent are all correctly fired for horses.
This commit fixes BUKKIT-4393.
Cancelling InventoryDragEvent causes the placed items to be lost. This is
because the cursor is set to the result prior to the event taking place,
so the items are removed from the cursor. When the event is cancelled, the
items removed from the cursor aren't placed in the inventory, and are just
lost.
This change sets the cursor back to the original cursor when the event is
cancelled.
Cancelling an InventoryClickEvent for a single click causes the click not
to be processed by the clicked inventory. The server then doesn't
correctly identify their second click as being a double click, causing an
inconsistency between what the Player believes the inventory to be and
what the server believes the inventory to be.
This change forces an updateInventory call whenever an InventoryClickEvent
whose action is NOTHING is cancelled. Both clicks are considered
PICKUP_ALL, so updating the inventory after the second click fixes any
inconsistencies that could arise between the client and the server.
Currently, the method used for calculating the damage of zombies is scaled
to their health, but it uses the default max health rather than the real
max health value. If zombies have more health than the default max health
value, the amount of damage they deal becomes negative.
This is caused by EntityZombie.getMaxHealth() returning a hardcoded value of
20, which is the vanilla max health for zombies. Rather than using this value
when calculating zombie damage, the call is changed to instead use
((CraftLivingEntity) this.bukkitEntity).getMaxHealth(). This uses the true
maximum health of the Entity. "this.maxHealth" could be used instead of the
aforementioned method, however that creates a very unclear diff, and a
confusing change.
When a Player drops an ItemStack while in creative mode by placing it outside
of their inventory window, the slot number in the packet is -1. The check
that was added to avoid throwing InventoryCreativeEvent excessively didn't
take this into account, and would cause an ArrayIndexOutOfBoundsException to
be thrown when attempting to get the slot specified by the packet.
This change shorts the invocation of player.defaultContainer.getSlot(
packet107setcreativeslot.b) to only occur if the slot id is within the range
of the Inventory. This prevents attempting to get the slot from a location
that is actually outside of the Inventory.
This commit brings the InventoryClickEvent up to date with the new Minecraft
changes in 1.5.
InventoryDragEvent (thanks to @YLivay for his PR) is added to represent the
new "dragging" or "painting" functionality, where if you hold an itemstack and
click-drag over several slots, the items will be split evenly (left click) or
1 each (right click).
The ClickType enum is used to represent what the client did to trigger the
event.
The InventoryAction enum is reserved for future expansion, but will be used to
indicate the approximate result of the action.
Additionally, handling of creative inventory editing is improved with the new
InventoryCreativeEvent, and handling of numberkey presses is also improved
within InventoryClickEvent and CraftItemEvent.
Also, cancelling a creative click now displays properly on the client.
Adresses BUKKIT-3692, BUKKIT-4035, BUKKIT-3859 (new 1.5 events),
BUKKIT-2659, BUKKIT-3043, BUKKIT-2659, and BUKKIT-2897 (creative click events).
We only go through event creation and calling when dispensing filled buckets
if the bucket is able to place its liquid. However, the check for this is
incorrect so the event is not called when a block liquids can destroy is
in front of the dispenser. This commit fixes the check to match the checks
vanilla does when actually using the bucket.
The CraftBlock class is setting bit 0x4 of the update flag when bit 0x2
should in fact be set here. Bit 0x2 means "do updates"; bit 0x4 means
"don't do updates if the world is static, even when bit 0x2 is set".
Minecraft 1.5.2 changed mob spawning by ignoring persistent mobs from the
mob count. In CraftBukkit all mobs that previously used a separate hard
coded persistence system were ported to instead use this one. This causes
all animals to be persistent by default and thus never be counted. To
correct this issue we consider if the mob would be considered persistent
in the hard coded system as well when deciding if a mob should count.
Currently there are several cases where a player will have their inventory
screen closed client side but we will not call an event. To correct this
we call the event when the server is the cause of the inventory closing
instead of just when the client is the cause. We also ensure the server is
closing the inventory reliably so we get the events. Additionally this
commit also calls the event when a player disconnects which will handle
kicks, quits, and server shutdown.
As an optimization we don't do any movement processing on entities that
have not moved. However, players in minecarts trigger this condition when
the minecart is moving on its own. This causes issues with things that rely
on player collision like tripwires. To correct this and any future related
issues we always handle movement for passengers and their vehicles even
if one of the two hasn't moved since they are linked.
When converting things in Minecraft to use wall time instead of ticks I
realized we'd run into integer division rounding issues and could have
updates that end up counting as zero ticks. To compensate for this the
code ensures we always process at least one tick. However, every time we
end up with zero ticks the next time we have an extra tick due to rounding
the other way with the leftovers. This means we are going far too fast and
should not have this at least one tick logic at all.
On top of this some potions rely on the number of ticks they run and not
just the amount of time they last and so potions were put back to running
with ticks entirely.
If a chunk has somehow managed to save with arrays that are not 4096
entries long when reading them again we will get exceptions. Checking the
array length and resizing if needed is cheap so we should do this to help
avoid crashing servers due to this error.
When a chunk is being loaded the server checks to ensure the chunk's idea
of where it is located matches where it was located in the region file. If
these two values do not match the chunk's idea of its position is updated
and the chunk is reloaded. In vanilla minecraft this loading involves the
chunk's tile entities as well. With the change to loading player chunks
asynchronously we split loading tile entities to a separate step that takes
place after this check. Because of this tile entities are loaded with
invalid locations that result in trying to fetch block data from negative
or too large positions in the chunk's internal block storage arrays.
Because loading the tile entities is not thread safe we cannot return to
vanilla behavior here. Instead when we detect a misplaced chunk we just
edit the NBT data for the chunk to relocate the tile entities. This results
in them moving correctly with the chunk without having to actually load
them first.
If a hopper is unable to perform any action during a tick it attempts to do
so every tick from then on. Once it is able to do so it then sets a delay
before attempting to do something again. To avoid excessive CPU usage for
hoppers sitting idle we now apply this delay regardless of the success of
the action.
When using the new feature in 1.5 to drop the item in any highlighted slot,
the anvil result slot does not apply the full anvil calculation that picking
up the item does, including the experience calculation.
Currently furnace smelting and the item pickup delay timer use wall time
(aka actual time passed) to emulate a constant tick rate so run at the
same speed regardless of the server's actual tick rate. There are several
other places this makes sense so this commit converts them.
The item despawn timer is converted so now always takes 5 minutes. Users
know this 5 minute number well so keeping this constant helps to avoid
confusion. This also helps alleviate lag because if a large number of item
drops is the reason your server is running slowly having them stay around
longer just means your server is slow longer.
Potion brewing and the zombie villager conversion timer are now constant.
These match the furnace criteria of being useful for hiding lag and not
having a detrimental effect on gameplay.
Potion effects are now also using wall time. The client is told about effect
times in ticks and displays this information to the user as minutes and
seconds assuming a solid 20 ticks per second. The server does have
code for updating the client with the current time remaining to help
avoid skew due to differing tick rates but making this a constant makes
sense due to this display.
Add a check to avoid doing movement work if an entity doesn't move. This
usually will not ever happen in the current server but is useful when it
does and will be more useful in the future.
Only process mob on mob (non-player) collisions every other tick. Players
tend to pack a lot of mobs into a small space (sheep farm, mob grinder, etc)
so they do a lot of work processing collisions. To help alleviate some of
this we only run these calculations every other tick. This has no visible
effect on the client but can be a huge win on the server depending on
circumstances.
Use generic entity inWater checking for squids. Squids have their own logic
currently for determining if they are in water. This check is almost
identical to the generic entity checking which is run anyway. To avoid
doing duplicate work we just remove the squid version. This does not
have any noticeable effect on gameplay since the checks are so similar.
Use HashSet for tile entities instead of ArrayList. Using an ArrayList for
storing tile entities in a world means we have very expensive inserts and
removes that aren't at the end of the array due to the array copy this
causes. This is most noticeable during chunk unload when a large number of
tile entities are removed from the world at once. Using a HashSet here uses
a little more memory but is O(1) for all operations so removes this
bottleneck.
When a player comes into range of an entity in a vehicle they will often be
sent the spawn packet for the rider before receiving one for the vehicle.
This causes the attachment packet to fail client side because it attempts
to attach the rider to a vehicle that doesn't exist on the client. To
correct this we account for both possible orderings and send the
attachment packet appropriately.
Vanilla also sends an new attach packet every 60 ticks even if the vehicle
has not changed. As this packet is a toggle this resulting in players
teleporting around randomly. Since we handle attachments properly now we
simply revert this section to use the 1.4 logic.
When looking up tile entities for a chunk to send to a player we currently
loop through every tile entity in the world checking if it is within the
bounds of the relevant chunk. Instead of doing this we can just use the
tile entities list stored in the chunk to avoid this costly searching.
As a further optimization, we also modify the generic range-based lookup
to use chunks as well. For most lookups this will give a smaller search
pool which will result in faster lookups.
Thanks to @mikeprimm for the idea and most of the implementation.
In certain scenarios a boat can be killed multiple ways in a single tick.
Due to improper guards this can cause the death code to run multiple times
creating item drops. To correct this we insert the appropriate death check.
Two connection status checks were added to setting a scoreboard for a
player. The first checks to see if a player has logged in yet, which
implicates the ability to receive packets. The second checks to affirm
that the CraftPlayer reference is still to a logged in player; setting
it while not logged in would maintain a stale player reference in the
scoreboard manager.
The method's return value was being incorrectly calculated from the
perspective of this.canHurt(that), where it's actually used from the
this.canBeHurtBy(that) perspective.
The method getTeam gets the team from name of, as opposed to getting the
team a player belongs to.
This also addresses BUKKIT-4002 and partially BUKKIT-4044
When a world is created using our API, it does not use secondary world
server and will maintain a reference to its own scoreboard. In vanilla,
this is not an issue as there is only ever one world.
Similarly to maps, an overwrite to the scoreboard reference has been
added for when another world has been created.
This should also address BUKKIT-3982 and BUKKIT-3985
In commit 7710efc5f9 we corrected the handling of large chests as the
destination for hoppers moving items but did not apply the same fix for
large chests being the source or for droppers. This commit updates these
to have the same fix.
This implementation facilitates the correspondence of the Bukkit Scoreboard
API to the internal minecraft implementation.
When the first scoreboard is loaded, the scoreboard manager will be created.
It uses the newly added WeakCollection for handling plugin scoreboard
references to update the respective objectives. When a scoreboard contains no
more active references, it should be garbage collected.
An active reference can be held by a still registered objective, team, and
transitively a score for a still registered objective. An internal reference
will also be kept if a player's specific scoreboard has been set, and will
remain persistent until that player logs out.
A player's specific scoreboard becomes the scoreboard used when determining
team structure for the player's attacking damage and the player's vision.
This class is designed to be an invisible layer between a normal collection,
and one that silently loses entries because they are only weakly referencable.
Some operations have additional overhead to be semantically correct, but it
maintains the equals contract for all entries, as opposed to identity.
It does not support the equals or hash code method as it cannot easily have
the transitive and commutative properties.
This adds calls to BlockRedstoneEvent for the new daylight sensor and
trapped chest blocks. Note that the redstone level for trapped chests
cannot be modified, as it is based on the number of players currently
viewing the chest's inventory.
When an array of an inventory's contents is requested, we loop through the contents of the NMS inventory's ItemStacks in order to return Bukkit ItemStacks that can be used through the API. However, the NMS ItemStack can, in some cases, be larger than the physical size of the inventory. Using the size of the NMS array as a limit on the loop that follows can result in an ArrayIndexOutOfBoundsException because the Bukkit array's length is the actual size of the inventory, and thus will be smaller.
With this commit we use the smaller of the two arrays' length as the limit in the loop, thus eliminating the possibility that the smaller array will be asked for an index higher than its length.
When a block placement happens we currently update physics on the
attempted placement and update again if the placement is cancelled.
To correct the first one we simply set the block without applying
physics. To correct the second we have to add a new method to
BlockState that lets us update without applying physics and use
this method method when putting the block back.
Without this check, any non-null reference to a plugin is considered
'valid' for registering a task in the scheduler. This is obviously
unintentional behavior and has been changed to throw an
IllegalPluginAccessException. It is now consistent with the
SimplePluginManager event registration contract.
This in affect also addresses BUKKIT-3950 for uninitialized plugin
references (ones without a description).
Large chests work in a different fashion as they are a combination of
two other inventories. This causes their getOwner method to always return
null as their is no correct return. To compensate for this for the hopper
events we special case them to use their CraftBukkit counterpart that has
the information we need for the event.
When a splash potion has no applicable effects we currently do not call
PotionSplashEvent. This means plugins are unable to make custom
potions with reliable splash handling as they have to relicate the
functionality themselves.
With this commit we simply make the event fire regardless of the effects
on the potion.
When cloning an item, all references are copied to the new item. For
collections, this makes internal changes become visible in both the old and
new items.
In CraftMetaItem, clone was not making copies of the appropriate collections
and has been fixed for non-null values.
In CraftMetaEnchantedBook and CraftMetaPotion, clone was using possible empty
collection references and has been changed to explicitly null-check instead.
I should try to compile before I say "this change is okay".
I should try to compile before I say "this change is okay".
I should try to compile before I say "this change is okay".
I should try to compile before I say "this change is okay".
for i in range(100)
This causes the server to generate PrepareItemEnchantEvent even in the
case that an item is already enchanted or otherwise would normally not
be enchantable.
The client resets all formatting after a color code is received, but currently the ANSI codes do not, and so the console does not accurately reflect the appearance of the formatted text. Instead, the ANSI color codes are now set to reset all text attributes.
Currently when dealing with physical interactions with pressure plates
and tripwires we immediately block their activation as soon as a single
entity involved has their event cancelled. We also fire events whenever
an entity intersects the block a wooden button is in even if they aren't
actually pressing it. To correct this we move the button interaction to
the correct place and modify all three to only block the activation if
every entity is blocked from using them instead of just one of them.
CraftServer methods that implement the Server interface will throw an
IllegalArgumentException if a method cannot operate on a null input
and given a null pointer.
This causes methods to fail early and identify that a plugin is
responsible for passing in an invalid argument. This will only
change the exception thrown, if there originally was a thrown
exception. This helps with hunting down legitimate problems
with CraftBukkit.
If the server changes the weather it will set the per-player weather
variable and future changes will not apply. We should only set this
variable when a plugin is requesting per-player weather and not when
the server it doing it.
We used to fall Item.filterData() for this but that method is meant for
converting item data to block data during placement and does the wrong
thing for this case. Instead we just see if the item should have data and
if not set it to zero. We also have to filter wool data explicitly because
clients crash when given invalid wool data.
In Minecraft 1.5 saplings do not grow with a single use of bonemeal anymore.
Our code assumes they will and only takes away bonemeal from the player
when the tree grows successfully (not cancelled by a plugin). Instead we
now always remove a bonemeal even if a plugin is the reason a tree didn't
grow as this matches the vanilla logic more closely.
If a custom TravelAgent is used and returns null for findOrCreate method
a NullPointerException will occur.
Conflicts:
src/main/java/net/minecraft/server/PlayerList.java
Currently, CraftTravelAgent will call s() on the passed-in WorldServer in order to set DEFAULT. However, s() will always return null at this point, because WorldServer.P will still be null, as it is set after the constructor is called. Instead, we set CraftTravelAgent.DEFAULT to the instance that is being constructed.
Recent changes caused PlayerPortalEvent to suddenly return null
unexpectedly and could end up in NPEs resulting that did not before.
This commit addresses that situation by always ensuring a TravelAgent
instance is returned.
The TravelAgent for world 0 is returned arbitrarily in an effort to
compensate for plugins that are implementation dependent and expect some
form of a TravelAgent to be accessible in the event at all times.
Vanilla does not check for blocks in which the player could
suffocate when changing dimension, so portals will happily spawn
players in blocks when using a portal under certain
circumstances. However, we currently check for these instances
and move the player up until they will not suffocate. This means
that players can sometimes be taken to above the target portal,
making it seem as if a portal was not created. Instead, we now
disable this suffocation check when moveToWorld is called from
changeDimension, mirroring vanilla behavior more accurately.
Due to the having to generate new logic to avoid using the customized
PlayerConnection.moveToWorld, entities returning from The End were not
properly calculating their exit target. This commit corrects that
logic.
By having a single function to process BlockPlacement logic, we make
it so that there is consistent behavior throughout all BlockPlace
events. This should allow for easier troubleshooting and less diffs
in source.
This also fixes BUKKIT-3463 by including the correct coordinates that
were clicked to the event.
Also fixes: BUKKIT-3477 and BUKKIT-3488
Minecraft likes to double check that tile entities get set after they
are placed, however we didn't set tile entities until after our event
was called. This caused the world to have multiple tile entities in a
single block location; to fix this we now set tile entities before
the event.
When the skull BlockPlaceEvent was added it was made so the event
would be called after all the data has been set, however this is a
behavior change that is inconsistent with other BlockPlaceEvents.
Instead, if people wish to get the block data they should schedule
a task.
Relates to: BUKKIT-3438
When either of those settings are false, the worlds are not loaded and
therefore will not be targeted for portal exits. Existing worlds are
iterated directly to avoid defaulting to the first world if a direct
dimension match is not found.
Plugins must also specify exit from custom Bukkit worlds to comply with
original commit: https://github.com/Bukkit/CraftBukkit/commit/2dc2af0
This commit introduces a constant to clarify the dependency on the
CraftBukkit implementation of custom worlds having a dimension offset.
By returning the following value (7) we remove the need to special
case pistons in any way (other than the original purpose of this
check, which is to ensure pistons have valid data)
The previous logic was faulty since it lost the logic of "placing" the
block. It was also taking into account data that could have been
changed outside of the processing of this event, which is irrelevant
to the processing of this event.
The javadocs state that a null may be used to remove the currently
playing sound, however this causes a NullPointerException.
It also doesn't process registering the record correctly, along with
processing non-valid items.
By using return 0, we exit the loop prematurely preventing other
creature types from being spawned if one type is set to 0. By using
continue we move on to the other types and allow them to spawn
properly.
Fixes BUKKIT-3408, BUKKIT-3190, BUKKIT-3191, BUKKIT-3407
These changes relate mostly to semantical changes for serialization
contract, exception of changing the map scaling value from byte to boolean,
what it should have been in the first place. Appropriate unit tests were
added for CraftMapMeta, as they were missing.
This makes it so animals (tame or not) will sit properly and not move
around.
Wild animals that are sitting may override the sitting position if
they are attacking.
The 'tag' NBTTagCompound field of the ItemStack assumes that it is OK to
save a reference to an NBT supplied via load() and assumes it is OK to
supply a reference to the internal field during a save(). Neither is true,
as Chunk NBT structures are required to be read-only once created (due to
being written asynchronously off the server thread AND due to the potential
to be passed to a new Chunk if the same chunk is reloaded before the
writing of the NBT is completed by the File I/O thread). Keeping a live
reference to the NBT copy passed in, or to the NBT value passed back
during saving, creates serious thread safety issues which can result in
corrupted data being written to the world data files.
The specific issue here was uncovered by the recent change to use
setName("") on the ItemStack.tag object. When a chunk is being loaded
again before its save is completed, this results in name of the field
in the NBT being set to "". This causes it to be saved as "" instead
of "tag" resulting in it not being properly reloaded in the future which
results in the itemstack losing all of its metadata.
Teleportation should never be processed on dead entities. If you wish
to teleport an entity, do it on a living entity. If you wish to
teleport a player, set their respawn location in PlayerRespawnEvent.
This adds two settings to bukkit.yml, allowing activation and control of
two chunk garbage collection triggering conditions:
chunk-gc/period-in-ticks controls a periodic GC, run once every N ticks
(default is 600); chunk-gc/load-threshold causes the GC to run once
after every N calls to loadChunk() on a given world (this call is an API
call used by plugins, and is distinct from the path taken for routine
player movement-based loading). In both cases, setting to zero will
disable the given GC scheduling strategy.
In either case, the act of doing the GC is simply one of scanning the
loaded chunks, seeing which are NOT being used by one or more players
(due to view-distance) and which are not already queued for unload, and
queueing them for a normal unload. Ultimately, the unload is then
processed the same as if the chunk were unloaded due to leaving the
view-distance range of all players, so the impact on plugins should be
no different (and strategies such as handling the ChunkUnloadEvent in
order to prevent unload will still work).
The initial interval for the periodic GC is randomized on a per-world
basis, in order to avoid all world being GCed at the same time -
minimizing potential lag spikes.
With the persistence api introduced, pets did not have their
persistence flag updated to reflect their persistence. This caused
tame ocelots to not persist under specific conditions.
Slimes and wolves have health that can change based on certain
conditions. So we check if their max health should be updated, and if
it has been customized in any way.
We also scale the wolf's health for their tail
An ItemStack gains the tag name "tag" when the stack is serialized
to NBT, however items don't have a tag *until* they are serialized at
least once. So to solve this, we remove the tag name when loading the
NBT data.
Another problem with NBT are TagLists, when transferring tag lists
between the server and the client the names are lost, and so we
simply don't add a name to the tag.