Fixed pony data change event being triggered multipled times

src/main/java/com/minelittlepony/api/pony/IPony.java

@@ -1,10 +1,14 @@
 package com.minelittlepony.api.pony;
 
 import net.minecraft.util.Identifier;
+
+import org.jetbrains.annotations.Nullable;
+
+import com.google.common.collect.ComparisonChain;
 import com.minelittlepony.api.pony.meta.Race;
 import com.minelittlepony.client.MineLittlePony;
 
-public interface IPony {
+public interface IPony extends Comparable<IPony> {
 
     /**
      * Gets the global pony manager instance.
@@ -48,4 +52,13 @@ public interface IPony {
      * Gets the metadata associated with this pony's model texture.
      */
     IPonyData metadata();
+
+
+    @Override
+    default int compareTo(@Nullable IPony o) {
+        return o == this ? 0 : o == null ? 1 : ComparisonChain.start()
+                .compare(texture(), o.texture())
+                .compare(metadata(), o.metadata())
+                .result();
+    }
 }

src/main/java/com/minelittlepony/api/pony/IPonyData.java

@@ -1,5 +1,8 @@
 package com.minelittlepony.api.pony;
 
+import org.jetbrains.annotations.Nullable;
+
+import com.google.common.collect.ComparisonChain;
 import com.minelittlepony.api.pony.meta.Gender;
 import com.minelittlepony.api.pony.meta.Race;
 import com.minelittlepony.api.pony.meta.Size;
@@ -7,13 +10,14 @@ import com.minelittlepony.api.pony.meta.TailLength;
 import com.minelittlepony.api.pony.meta.Wearable;
 import com.minelittlepony.common.util.animation.Interpolator;
 
+import java.util.Arrays;
 import java.util.Map;
 import java.util.UUID;
 
 /**
  * Metadata for a pony.
  */
-public interface IPonyData {
+public interface IPonyData extends Comparable<IPonyData> {
     /**
      * Gets this pony's race.
      */
@@ -70,4 +74,16 @@ public interface IPonyData {
      * Gets the trigger pixel values as they appeared in the underlying image.
      */
     Map<String, TriggerPixelType<?>> getTriggerPixels();
+
+    @Override
+    default int compareTo(@Nullable IPonyData o) {
+        return o == this ? 0  : o == null ? 1 : ComparisonChain.start()
+                .compare(getRace(), o.getRace())
+                .compare(getTail(), o.getTail())
+                .compare(getGender(), o.getGender())
+                .compare(getSize().ordinal(), o.getSize().ordinal())
+                .compare(getGlowColor(), o.getGlowColor())
+                .compare(0, Arrays.compare(getGear(), o.getGear()))
+                .result();
+    }
 }

src/main/java/com/minelittlepony/client/mixin/MixinClientPlayerEntity.java

@@ -9,6 +9,8 @@ import net.minecraft.client.network.ClientPlayerEntity;
 import net.minecraft.entity.Entity;
 import net.minecraft.entity.EntityDimensions;
 import net.minecraft.entity.EntityPose;
+
+import org.jetbrains.annotations.Nullable;
 import org.spongepowered.asm.mixin.Mixin;
 import org.spongepowered.asm.mixin.injection.At;
 import org.spongepowered.asm.mixin.injection.Inject;
@@ -19,7 +21,8 @@ import org.spongepowered.asm.mixin.injection.callback.CallbackInfoReturnable;
 abstract class MixinClientPlayerEntity extends AbstractClientPlayerEntity implements Pony.RegistrationHandler {
     public MixinClientPlayerEntity() { super(null, null); }
 
-    private Pony pony;
+    @Nullable
+    private IPony pony;
 
     @Inject(method = "startRiding(Lnet/minecraft/entity/Entity;Z)Z", at = @At("RETURN"))
     private void onStartRiding(Entity entity, boolean bl, CallbackInfoReturnable<Boolean> info) {
@@ -32,9 +35,9 @@ abstract class MixinClientPlayerEntity extends AbstractClientPlayerEntity implem
     }
 
     @Override
-    public boolean shouldUpdateRegistration(Pony pony) {
-        if (this.pony != pony) {
-            this.pony = pony;
+    public boolean shouldUpdateRegistration(IPony pony) {
+        if (this.pony != pony && (this.pony == null || this.pony.metadata().compareTo(pony.metadata()) != 0)) {
+            this.pony = Pony.snapshot(pony);
             return true;
         }
         return false;

src/main/java/com/minelittlepony/client/pony/Pony.java

@@ -69,4 +69,8 @@ public class Pony implements IPony {
     public interface RegistrationHandler {
         boolean shouldUpdateRegistration(IPony pony);
     }
+
+    public static IPony snapshot(IPony pony) {
+        return new Pony(pony.texture(), Memoize.of(new MsgPonyData(pony.metadata(), pony.defaulted())));
+    }
 }