Paper/Spigot-Server-Patches/0305-Vanished-players-don-t-have-rights.patch

From c00e706c2239a7aef32a535ab1433f84706bbb4a 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 89a83548b8..9339b3255d 100644
--- a/src/main/java/net/minecraft/server/Entity.java
+++ b/src/main/java/net/minecraft/server/Entity.java
@@ -94,7 +94,7 @@ public abstract class Entity implements INamableTileEntity, ICommandListener, Ke
     private static int entityCount;
     private final EntityTypes<?> g; public EntityTypes<?> getEntityType() { return g; } // Paper - OBFHELPER
     private int id;
-    public boolean j;
+    public boolean j; public boolean blocksEntitySpawning() { return j; } // Paper - OBFHELPER
     public final List<Entity> passengers;
     protected int k;
     private Entity vehicle;
diff --git a/src/main/java/net/minecraft/server/IBlockData.java b/src/main/java/net/minecraft/server/IBlockData.java
index 24ce9137ae..bf06a90312 100644
--- a/src/main/java/net/minecraft/server/IBlockData.java
+++ b/src/main/java/net/minecraft/server/IBlockData.java
@@ -165,6 +165,7 @@ public interface IBlockData extends IBlockDataHolder<IBlockData> {
         return this.getBlock().a(this, iblockaccess, blockposition);
     }
 
+    default VoxelShape getBlockShape(IBlockAccess iblockaccess, BlockPosition blockposition) { return h(iblockaccess, blockposition); } // Paper - OBFHELPER
     default VoxelShape h(IBlockAccess iblockaccess, BlockPosition blockposition) {
         return this.getBlock().f(this, iblockaccess, blockposition);
     }
diff --git a/src/main/java/net/minecraft/server/ItemBlock.java b/src/main/java/net/minecraft/server/ItemBlock.java
index 1cecccef23..afc881d9af 100644
--- a/src/main/java/net/minecraft/server/ItemBlock.java
+++ b/src/main/java/net/minecraft/server/ItemBlock.java
@@ -70,7 +70,8 @@ public class ItemBlock extends Item {
 
     protected boolean b(BlockActionContext blockactioncontext, IBlockData iblockdata) {
         // CraftBukkit start - store default return
-        boolean defaultReturn = iblockdata.canPlace(blockactioncontext.getWorld(), blockactioncontext.getClickPosition()) && blockactioncontext.getWorld().a(iblockdata, blockactioncontext.getClickPosition());
+        final World world = blockactioncontext.getWorld(); // Paper
+        boolean defaultReturn = iblockdata.canPlace(world, blockactioncontext.getClickPosition()) && world.a(iblockdata, blockactioncontext.getClickPosition()) && world.checkNoVisiblePlayerCollisions(blockactioncontext.getEntity(), iblockdata.getBlockShape(world, blockactioncontext.getClickPosition())); // Paper - Use our entity search
 
         BlockCanBuildEvent event = new BlockCanBuildEvent(CraftBlock.at(blockactioncontext.getWorld(), blockactioncontext.getClickPosition()), CraftBlockData.fromData(iblockdata), defaultReturn);
         blockactioncontext.getWorld().getServer().getPluginManager().callEvent(event);
diff --git a/src/main/java/net/minecraft/server/VoxelShape.java b/src/main/java/net/minecraft/server/VoxelShape.java
index ea8f1c170a..fdfc0d442e 100644
--- a/src/main/java/net/minecraft/server/VoxelShape.java
+++ b/src/main/java/net/minecraft/server/VoxelShape.java
@@ -24,6 +24,7 @@ public abstract class VoxelShape {
         return i <= 0 ? Double.NEGATIVE_INFINITY : this.a(enumdirection$enumaxis, i);
     }
 
+    public AxisAlignedBB getBounds() { return a(); } // Paper - OBFHELPER
     public AxisAlignedBB a() {
         if (this.b()) {
             throw new UnsupportedOperationException("No bounds for empty shape.");
@@ -38,6 +39,7 @@ public abstract class VoxelShape {
 
     protected abstract DoubleList a(EnumDirection.EnumAxis var1);
 
+    public boolean isEmpty() { return b(); } // Paper - OBFHELPER
     public boolean b() {
         return this.a.a();
     }
diff --git a/src/main/java/net/minecraft/server/World.java b/src/main/java/net/minecraft/server/World.java
index caec2807a6..e7576c5c6a 100644
--- a/src/main/java/net/minecraft/server/World.java
+++ b/src/main/java/net/minecraft/server/World.java
@@ -1581,6 +1581,37 @@ public abstract class World implements IEntityAccess, GeneratorAccess, IIBlockAc
         }
     }
 
+    // Paper start - Based on method below
+    /**
+     * @param entity causing the action ex. block placer
+     * @param voxelshape area to search within
+     * @return if there are no visible players colliding
+     */
+    public boolean checkNoVisiblePlayerCollisions(@Nullable Entity entity, VoxelShape voxelshape) {
+        if (voxelshape.isEmpty()) {
+            return true;
+        } else {
+            List list = this.getEntities((Entity) null, voxelshape.getBounds());
+
+            for (int i = 0; i < list.size(); ++i) {
+                Entity entity1 = (Entity) list.get(i);
+
+                if (entity instanceof EntityPlayer && entity1 instanceof EntityPlayer) {
+                    if (!((EntityPlayer) entity).getBukkitEntity().canSee(((EntityPlayer) entity1).getBukkitEntity())) {
+                        continue;
+                    }
+                }
+
+                if (!entity1.dead && entity1.blocksEntitySpawning()) {
+                    return false;
+                }
+            }
+
+            return true;
+        }
+    }
+    // Paper end
+
     public boolean a(@Nullable Entity entity, VoxelShape voxelshape) {
         if (voxelshape.b()) {
             return true;
diff --git a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
index 1cc17c29c9..a61c32a2f3 100644
--- a/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
+++ b/src/main/java/org/bukkit/craftbukkit/event/CraftEventFactory.java
@@ -806,6 +806,14 @@ public class CraftEventFactory {
         Projectile projectile = (Projectile) entity.getBukkitEntity();
         org.bukkit.entity.Entity collided = position.entity.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;
     }
-- 
2.18.0