Fix World Capabilities NPE when there are no attached capabilities.

src/main/java/net/minecraftforge/common/util/WorldCapabilityData.java

@@ -26,7 +26,7 @@ public class WorldCapabilityData extends WorldSavedData
     public void readFromNBT(NBTTagCompound nbt)
     {
         this.capNBT = nbt;
-        if(serializable != null)
+        if (serializable != null)
         {
             serializable.deserializeNBT(this.capNBT);
             this.capNBT = null;
@@ -36,7 +36,9 @@ public class WorldCapabilityData extends WorldSavedData
     @Override
     public NBTTagCompound writeToNBT(NBTTagCompound nbt)
     {
-        return nbt = serializable.serializeNBT();
+        if (serializable != null)
+            nbt = serializable.serializeNBT();
+        return nbt;
     }
 
     @Override
@@ -48,7 +50,7 @@ public class WorldCapabilityData extends WorldSavedData
     public void setCapabilities(WorldProvider provider, INBTSerializable<NBTTagCompound> capabilities)
     {
         this.serializable = capabilities;
-        if(this.capNBT != null)
+        if (this.capNBT != null)
         {
             serializable.deserializeNBT(this.capNBT);
             this.capNBT = null;

src/main/java/net/minecraftforge/event/ForgeEventFactory.java

@@ -489,7 +489,7 @@ public class ForgeEventFactory
     {
         MinecraftForge.EVENT_BUS.post(new PotionBrewEvent.Post(brewingItemStacks));
     }
-    
+
     public static void onPlayerBrewedPotion(EntityPlayer player, ItemStack stack)
     {
         MinecraftForge.EVENT_BUS.post(new PlayerBrewedPotionEvent(player, stack));
@@ -525,7 +525,8 @@ public class ForgeEventFactory
         return gatherCapabilities(new AttachCapabilitiesEvent.Item(item, stack), parent);
     }
 
-    public static CapabilityDispatcher gatherCapabilities(World world, ICapabilityProvider parent) {
+    public static CapabilityDispatcher gatherCapabilities(World world, ICapabilityProvider parent)
+    {
         return gatherCapabilities(new AttachCapabilitiesEvent.World(world), parent);
     }
 

src/test/java/net/minecraftforge/test/NoBedSleepingTest.java

@@ -74,8 +74,11 @@ public class NoBedSleepingTest
     public static class EventHandler
     {
         @SubscribeEvent
-        public void onEntityConstruct(AttachCapabilitiesEvent evt)
+        public void onEntityConstruct(AttachCapabilitiesEvent.Entity evt)
         {
+            if (!(evt.getEntity() instanceof EntityPlayer))
+                return;
+
             evt.addCapability(new ResourceLocation(MODID, "IExtraSleeping"), new ICapabilitySerializable<NBTPrimitive>()
             {
                 IExtraSleeping inst = SLEEP_CAP.getDefaultInstance();

src/test/java/net/minecraftforge/test/WorldCapabilityRainTimerTest.java

@@ -1,16 +1,9 @@
 package net.minecraftforge.test;
 
-import java.util.Map;
-import java.util.Set;
-
-import com.google.common.collect.Maps;
-
 import net.minecraft.nbt.NBTBase;
 import net.minecraft.nbt.NBTTagCompound;
-import net.minecraft.nbt.NBTTagIntArray;
 import net.minecraft.util.EnumFacing;
 import net.minecraft.util.ResourceLocation;
-import net.minecraft.world.storage.WorldInfo;
 import net.minecraftforge.common.MinecraftForge;
 import net.minecraftforge.common.capabilities.Capability;
 import net.minecraftforge.common.capabilities.Capability.IStorage;
@@ -44,7 +37,8 @@ public class WorldCapabilityRainTimerTest {
         @SubscribeEvent
         public void attatchTimer(AttachCapabilitiesEvent.World event)
         {
-            event.addCapability(new ResourceLocation(MODID, "rainTimer"), new RainTimerProvider());
+            if (!event.getWorld().isRemote && !event.getWorld().provider.getHasNoSky())
+                event.addCapability(new ResourceLocation(MODID, "rainTimer"), new RainTimerProvider());
         }
 
         @SubscribeEvent
@@ -55,18 +49,22 @@ public class WorldCapabilityRainTimerTest {
 
             IRainTimer timer = event.world.getCapability(TIMER_CAP, null);
 
-            if(event.phase == TickEvent.Phase.END)
+            if (timer == null)
+                return;
+
+            if (event.phase == TickEvent.Phase.END)
                 timer.onTick();
 
-            if(event.phase == TickEvent.Phase.START)
+            if (event.phase == TickEvent.Phase.START)
             {
-                if(!event.world.provider.getHasNoSky() && event.world.isRaining())
+                if(event.world.isRaining())
                 {
-                    if(timer.getDuration() == 0)
+                    if (timer.getDuration() == 0)
                         timer.refreshTimer(1000, 0);
-                    else if(timer.isTimerReachedDuration())
+                    else if (timer.isTimerReachedDuration())
                         event.world.provider.resetRainAndThunder();
-                } else
+                }
+                else
                     timer.refreshTimer(0, 0);
             }
         }