PaperMC/patches/server/0827-Fix-sticky-pistons-and-BlockPistonRetractEvent.patch
Nassim Jahnke 1358d1e914
Updated Upstream (CraftBukkit/Spigot) (#7580)
Upstream has released updates that appear to apply and compile correctly.
This update has not been tested by PaperMC and as with ANY update, please do your own testing

Bukkit Changes:
881e06e5 PR-725: Add Item Unlimited Lifetime APIs

CraftBukkit Changes:
74c08312 SPIGOT-6962: Call EntityChangeBlockEvent when when FallingBlockEntity starts to fall
64db5126 SPIGOT-6959: Make /loot command ignore empty items for spawn
2d760831 Increase outdated build delay
9ed7e4fb SPIGOT-6138, SPIGOT-6415: Don't call CreatureSpawnEvent after cross-dimensional travel
fc4ad813 SPIGOT-6895: Trees grown with applyBoneMeal() don't fire the StructureGrowthEvent
59733a2e SPIGOT-6961: Actually return a copy of the ItemMeta

Spigot Changes:
ffceeae3 SPIGOT-6956: Drop unload queue patch as attempt at fixing stop issue
e19ddabd PR-1011: Add Item Unlimited Lifetime APIs
34d40b0e SPIGOT-2942: give command fires PlayerDropItemEvent, cancelling it causes Item Duplication
2022-03-13 08:47:54 +01:00

85 lines
5.3 KiB
Diff

From 0000000000000000000000000000000000000000 Mon Sep 17 00:00:00 2001
From: Jake Potrebic <jake.m.potrebic@gmail.com>
Date: Wed, 22 Dec 2021 09:51:48 -0800
Subject: [PATCH] Fix sticky pistons and BlockPistonRetractEvent
There is an explicit check in the handling code for empty pistons that
prevents sticky pistons from firing the event. However when we look back
at the history we see that this check was originally added so that ONLY
sticky pistons would fire the retract event. I'm not sure why.
https://hub.spigotmc.org/stash/projects/SPIGOT/repos/craftbukkit/commits/1092acbddf07edfa4100bc6824504ac75088e913
Over the course of several updates, the meaning of that field appears to
have changed from "is NOT sticky" to "is sticky". So now its having the
opposite effect. Only normal pistons fire the retraction event. And like
all things in CB, it's just been carried around since.
If we are to believe the history, the correct fix for this issue is to
flip it so it only fires for sticky pistons, but that puts us in a
bind. It's already firing for non-sticky pistons, changing it now would
likely result in breakage. Furthermore, there is little documentation as
to WHY that was ever intended to be the case.
Instead we opt to remove the check entirely so that the event fires for
all piston types.
Co-authored-by: Zach Brown <zach@zachbr.io>
Co-authored-by: Madeline Miller <mnmiller1@me.com>
diff --git a/src/main/java/net/minecraft/world/level/block/piston/PistonBaseBlock.java b/src/main/java/net/minecraft/world/level/block/piston/PistonBaseBlock.java
index 322b3119682fbab5e790ce9255e96a519f03143d..2e5803035a46f890e8bfc59908c0040f9a960703 100644
--- a/src/main/java/net/minecraft/world/level/block/piston/PistonBaseBlock.java
+++ b/src/main/java/net/minecraft/world/level/block/piston/PistonBaseBlock.java
@@ -145,15 +145,15 @@ public class PistonBaseBlock extends DirectionalBlock {
}
// CraftBukkit start
- if (!this.isSticky) {
- org.bukkit.block.Block block = world.getWorld().getBlockAt(pos.getX(), pos.getY(), pos.getZ());
- BlockPistonRetractEvent event = new BlockPistonRetractEvent(block, ImmutableList.<org.bukkit.block.Block>of(), CraftBlock.notchToBlockFace(enumdirection));
- world.getCraftServer().getPluginManager().callEvent(event);
-
- if (event.isCancelled()) {
- return;
- }
- }
+ // if (!this.isSticky) { // Paper - Move further down
+ // org.bukkit.block.Block block = world.getWorld().getBlockAt(pos.getX(), pos.getY(), pos.getZ());
+ // BlockPistonRetractEvent event = new BlockPistonRetractEvent(block, ImmutableList.<org.bukkit.block.Block>of(), CraftBlock.notchToBlockFace(enumdirection));
+ // world.getCraftServer().getPluginManager().callEvent(event);
+ //
+ // if (event.isCancelled()) {
+ // return;
+ // }
+ // }
// PAIL: checkME - what happened to setTypeAndData?
// CraftBukkit end
world.blockEvent(pos, this, b0, enumdirection.get3DDataValue());
@@ -235,6 +235,13 @@ public class PistonBaseBlock extends DirectionalBlock {
BlockState iblockdata1 = (BlockState) ((BlockState) Blocks.MOVING_PISTON.defaultBlockState().setValue(MovingPistonBlock.FACING, enumdirection)).setValue(MovingPistonBlock.TYPE, this.isSticky ? PistonType.STICKY : PistonType.DEFAULT);
+ // Paper start - Move empty piston retract call to fix multiple event fires
+ if (!this.isSticky) {
+ if (!new BlockPistonRetractEvent(CraftBlock.at(world, pos), java.util.Collections.emptyList(), CraftBlock.notchToBlockFace(enumdirection)).callEvent()) {
+ return false;
+ }
+ }
+ // Paper end
world.setBlock(pos, iblockdata1, 20);
world.setBlockEntity(MovingPistonBlock.newMovingBlockEntity(pos, iblockdata1, (BlockState) this.defaultBlockState().setValue(PistonBaseBlock.FACING, Direction.from3DDataValue(data & 7)), enumdirection, false, true)); // Paper - diff on change
world.blockUpdated(pos, iblockdata1.getBlock());
@@ -261,6 +268,13 @@ public class PistonBaseBlock extends DirectionalBlock {
if (type == 1 && !iblockdata2.isAir() && PistonBaseBlock.isPushable(iblockdata2, world, blockposition1, enumdirection.getOpposite(), false, enumdirection) && (iblockdata2.getPistonPushReaction() == PushReaction.NORMAL || iblockdata2.is(Blocks.PISTON) || iblockdata2.is(Blocks.STICKY_PISTON))) {
this.moveBlocks(world, pos, enumdirection, false);
} else {
+ // Paper start - fire BlockPistonRetractEvent for sticky pistons retracting nothing (air)
+ if (type == TRIGGER_CONTRACT && iblockdata2.isAir()) {
+ if (!new BlockPistonRetractEvent(CraftBlock.at(world, pos), java.util.Collections.emptyList(), CraftBlock.notchToBlockFace(enumdirection)).callEvent()) {
+ return false;
+ }
+ }
+ // Paper end
world.removeBlock(pos.relative(enumdirection), false);
}
}