From cf655db17ece1bd42693e41fc787aca3dd602f52 Mon Sep 17 00:00:00 2001
From: Hugo Manrique <hugmanrique@gmail.com>
Date: Mon, 23 Jul 2018 14:22:26 +0200
Subject: [PATCH] Vanished players don't have rights


diff --git a/src/main/java/net/minecraft/server/Entity.java b/src/main/java/net/minecraft/server/Entity.java
index 56adea9cf4..3397604a8a 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -97,7 +97,7 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, Ke
     private static double e = 1.0D;
     private final EntityTypes<?> f;
     private int id;
-    public boolean i;
+    public boolean i; public final boolean blocksEntitySpawning() { return this.i; } // Paper - OBFHELPER
     public final List<Entity> passengers;
     protected int j;
     private Entity vehicle;
diff --git a/src/main/java/net/minecraft/server/IEntityAccess.java b/src/main/java/net/minecraft/server/IEntityAccess.java
index ee22bb0387..e5a013ffd2 100644
--- a/src/main/java/net/minecraft/server/IEntityAccess.java
+++ b/src/main/java/net/minecraft/server/IEntityAccess.java
@@ -22,9 +22,18 @@ public interface IEntityAccess {
         return this.getEntities(entity, axisalignedbb, IEntitySelector.f);
     }
 
+    // Paper start
     default boolean a(@Nullable Entity entity, VoxelShape voxelshape) {
+        return this.checkEntityCollision(entity, voxelshape, false);
+    }
+    default boolean checkEntityCollision(Entity entity, VoxelShape voxelshape, boolean checkCanSee) {
         return voxelshape.isEmpty() ? true : this.getEntities(entity, voxelshape.getBoundingBox()).stream().filter((entity1) -> {
+            if (entity instanceof EntityPlayer && entity1 instanceof EntityPlayer
+                && !((EntityPlayer)entity).getBukkitEntity().canSee(((EntityPlayer)entity1).getBukkitEntity())) {
+                return false;
+            }
             return !entity1.dead && entity1.i && (entity == null || !entity1.x(entity));
+            // Paper end
         }).noneMatch((entity1) -> {
             return VoxelShapes.c(voxelshape, VoxelShapes.a(entity1.getBoundingBox()), OperatorBoolean.AND);
         });
diff --git a/src/main/java/net/minecraft/server/IWorldReader.java b/src/main/java/net/minecraft/server/IWorldReader.java
index 0930552b1f..c0aa21703f 100644
--- a/src/main/java/net/minecraft/server/IWorldReader.java
+++ b/src/main/java/net/minecraft/server/IWorldReader.java
@@ -95,7 +95,12 @@ public interface IWorldReader extends IIBlockAccess {
         return ChunkStatus.EMPTY;
     }
 
+    // Paper start
     default boolean a(IBlockData iblockdata, BlockPosition blockposition, VoxelShapeCollision voxelshapecollision) {
+        return this.checkEntityCollision(iblockdata, blockposition, voxelshapecollision, false);
+    }
+    default boolean checkEntityCollision(IBlockData iblockdata, BlockPosition blockposition, VoxelShapeCollision voxelshapecollision, boolean checkCanSee) {
+        // Paper end
         VoxelShape voxelshape = iblockdata.b((IBlockAccess) this, blockposition, voxelshapecollision);
 
         return voxelshape.isEmpty() || this.a((Entity) null, voxelshape.a((double) blockposition.getX(), (double) blockposition.getY(), (double) blockposition.getZ()));
diff --git a/src/main/java/net/minecraft/server/ItemBlock.java b/src/main/java/net/minecraft/server/ItemBlock.java
index 59b1e6ce2e..b90cc6652b 100644
--- a/src/main/java/net/minecraft/server/ItemBlock.java
+++ b/src/main/java/net/minecraft/server/ItemBlock.java
@@ -126,7 +126,8 @@ public class ItemBlock extends Item {
         EntityHuman entityhuman = blockactioncontext.getEntity();
         VoxelShapeCollision voxelshapecollision = entityhuman == null ? VoxelShapeCollision.a() : VoxelShapeCollision.a((Entity) entityhuman);
         // CraftBukkit start - store default return
-        boolean defaultReturn = (!this.d() || iblockdata.canPlace(blockactioncontext.getWorld(), blockactioncontext.getClickPosition())) && blockactioncontext.getWorld().a(iblockdata, blockactioncontext.getClickPosition(), voxelshapecollision);
+        final World world = blockactioncontext.getWorld(); // Paper
+        boolean defaultReturn = (!this.d() || iblockdata.canPlace(world, blockactioncontext.getClickPosition())) && world.checkEntityCollision(iblockdata, blockactioncontext.getClickPosition(), voxelshapecollision, true); // Paper
         org.bukkit.entity.Player player = (blockactioncontext.getEntity() instanceof EntityPlayer) ? (org.bukkit.entity.Player) blockactioncontext.getEntity().getBukkitEntity() : null;
 
         BlockCanBuildEvent event = new BlockCanBuildEvent(CraftBlock.at(blockactioncontext.getWorld(), blockactioncontext.getClickPosition()), player, CraftBlockData.fromData(iblockdata), defaultReturn);
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index b570e2778b..b0f827594b 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -1120,6 +1120,14 @@ public class CraftEventFactory {
         Projectile projectile = (Projectile) entity.getBukkitEntity();
         org.bukkit.entity.Entity collided = position.getEntity().getBukkitEntity();
         com.destroystokyo.paper.event.entity.ProjectileCollideEvent event = new com.destroystokyo.paper.event.entity.ProjectileCollideEvent(projectile, collided);
+
+        if (projectile.getShooter() instanceof Player && collided instanceof Player) {
+            if (!((Player) projectile.getShooter()).canSee((Player) collided)) {
+                event.setCancelled(true);
+                return event;
+            }
+        }
+
         Bukkit.getPluginManager().callEvent(event);
         return event;
     }
-- 
2.21.0