From 9df1e4b11e0d2d0fbf938cedae2da130d40cca89 Mon Sep 17 00:00:00 2001
From: LexManos <LexManos@gmail.com>
Date: Mon, 23 May 2016 15:30:20 -0700
Subject: [PATCH] Take capabilities into account when comparing ItemStack
 NBT's. Closes #2726

---
 .../net/minecraft/item/ItemStack.java.patch   | 42 +++++++++++++++++--
 .../capabilities/CapabilityDispatcher.java    |  7 ++++
 2 files changed, 45 insertions(+), 4 deletions(-)

diff --git a/patches/minecraft/net/minecraft/item/ItemStack.java.patch b/patches/minecraft/net/minecraft/item/ItemStack.java.patch
index 39a3c359c6..8d9ed7a16a 100644
--- a/patches/minecraft/net/minecraft/item/ItemStack.java.patch
+++ b/patches/minecraft/net/minecraft/item/ItemStack.java.patch
@@ -164,7 +164,41 @@
  
          if (this.field_77990_d != null)
          {
-@@ -762,6 +768,7 @@
+@@ -352,7 +358,19 @@
+ 
+     public static boolean func_77970_a(@Nullable ItemStack p_77970_0_, @Nullable ItemStack p_77970_1_)
+     {
+-        return p_77970_0_ == null && p_77970_1_ == null ? true : (p_77970_0_ != null && p_77970_1_ != null ? (p_77970_0_.field_77990_d == null && p_77970_1_.field_77990_d != null ? false : p_77970_0_.field_77990_d == null || p_77970_0_.field_77990_d.equals(p_77970_1_.field_77990_d)) : false);
++        if (p_77970_0_ == null && p_77970_1_ == null) return true;
++        if (p_77970_0_ == null && p_77970_1_ != null) return false;
++        if (p_77970_0_ != null && p_77970_1_ == null) return false;
++        if (p_77970_0_.field_77990_d == null && p_77970_1_.field_77990_d != null) return false;
++        if (p_77970_0_.field_77990_d != null && p_77970_1_.field_77990_d == null) return false;
++        if (p_77970_0_.field_77990_d != null && !p_77970_0_.field_77990_d.equals(p_77970_1_.field_77990_d)) return false;
++        if (p_77970_0_.capabilities != null || p_77970_1_.capabilities != null)
++        {
++            boolean ret = p_77970_0_.capabilities != null ? p_77970_0_.capabilities.areCompatible(p_77970_1_.capabilities) : p_77970_1_.capabilities.areCompatible(null);
++            if (!ret) return false;
++        }
++
++        return true;
+     }
+ 
+     public static boolean func_77989_b(@Nullable ItemStack p_77989_0_, @Nullable ItemStack p_77989_1_)
+@@ -362,7 +380,11 @@
+ 
+     private boolean func_77959_d(ItemStack p_77959_1_)
+     {
+-        return this.field_77994_a != p_77959_1_.field_77994_a ? false : (this.field_151002_e != p_77959_1_.field_151002_e ? false : (this.field_77991_e != p_77959_1_.field_77991_e ? false : (this.field_77990_d == null && p_77959_1_.field_77990_d != null ? false : this.field_77990_d == null || this.field_77990_d.equals(p_77959_1_.field_77990_d))));
++        if (this.field_77994_a != p_77959_1_.field_77994_a) return false;
++        if (this.field_151002_e != p_77959_1_.field_151002_e) return false;
++        if (this.field_77991_e != p_77959_1_.field_77991_e) return false;
++        if (!ItemStack.func_77970_a(this, p_77959_1_)) return false;
++        return true;
+     }
+ 
+     public static boolean func_179545_c(@Nullable ItemStack p_179545_0_, @Nullable ItemStack p_179545_1_)
+@@ -762,6 +784,7 @@
              }
          }
  
@@ -172,7 +206,7 @@
          return list;
      }
  
-@@ -873,7 +880,7 @@
+@@ -873,7 +896,7 @@
          }
          else
          {
@@ -181,7 +215,7 @@
          }
  
          return multimap;
-@@ -906,6 +913,18 @@
+@@ -906,6 +929,18 @@
      @Deprecated
      public void func_150996_a(Item p_150996_1_)
      {
@@ -200,7 +234,7 @@
          this.field_151002_e = p_150996_1_;
      }
  
-@@ -991,4 +1010,26 @@
+@@ -991,4 +1026,26 @@
              return false;
          }
      }
diff --git a/src/main/java/net/minecraftforge/common/capabilities/CapabilityDispatcher.java b/src/main/java/net/minecraftforge/common/capabilities/CapabilityDispatcher.java
index 145378db28..ae36f7f8f3 100644
--- a/src/main/java/net/minecraftforge/common/capabilities/CapabilityDispatcher.java
+++ b/src/main/java/net/minecraftforge/common/capabilities/CapabilityDispatcher.java
@@ -114,4 +114,11 @@ public final class CapabilityDispatcher implements INBTSerializable<NBTTagCompou
             }
         }
     }
+
+    public boolean areCompatible(CapabilityDispatcher other) //Called from ItemStack to compare equality.
+    {                                                        // Only compares serializeable caps.
+        if (other == null) return this.writers.length == 0;  // Done this way so we can do some pre-checks before doing the costly NBT serialization and compare
+        if (this.writers.length == 0) return other.writers.length == 0;
+        return this.serializeNBT().equals(other.serializeNBT());
+    }
 }