Fix keepinv policies ignoring offhand (#4725)

Essentials/src/main/java/com/earth2me/essentials/EssentialsEntityListener.java

@@ -1,5 +1,6 @@
 package com.earth2me.essentials;
 
+import com.earth2me.essentials.utils.MaterialUtil;
 import com.earth2me.essentials.utils.VersionUtil;
 import net.ess3.api.IEssentials;
 import org.bukkit.Location;
@@ -198,7 +199,7 @@ public class EssentialsEntityListener implements Listener {
             final ISettings.KeepInvPolicy bind = ess.getSettings().getBindingItemsPolicy();
             if (VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_11_2_R01) && (vanish != ISettings.KeepInvPolicy.KEEP || bind != ISettings.KeepInvPolicy.KEEP)) {
                 for (final ItemStack stack : event.getEntity().getInventory()) {
-                    if (stack != null) {
+                    if (stack != null && !MaterialUtil.isAir(stack.getType())) {
                         if (stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE)) {
                             if (vanish == ISettings.KeepInvPolicy.DELETE) {
                                 event.getEntity().getInventory().remove(stack);
@@ -217,10 +218,12 @@ public class EssentialsEntityListener implements Listener {
                         }
                     }
                 }
+
+                // Now check armor
                 final ItemStack[] armor = event.getEntity().getInventory().getArmorContents();
                 for (int i = 0; i < armor.length; i++) {
                     final ItemStack stack = armor[i];
-                    if (stack != null) {
+                    if (stack != null && !MaterialUtil.isAir(stack.getType())) {
                         if (stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE)) {
                             if (vanish == ISettings.KeepInvPolicy.DELETE) {
                                 armor[i] = null;
@@ -244,6 +247,24 @@ public class EssentialsEntityListener implements Listener {
                     }
                 }
                 event.getEntity().getInventory().setArmorContents(armor);
+
+                // Now check offhand
+                if (VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_9_R01)) {
+                    final ItemStack stack = event.getEntity().getInventory().getItemInOffHand();
+                    //noinspection ConstantConditions
+                    if (stack != null && !MaterialUtil.isAir(stack.getType())) {
+                        final boolean isVanish = stack.getEnchantments().containsKey(Enchantment.VANISHING_CURSE);
+                        final boolean isBind = stack.getEnchantments().containsKey(Enchantment.BINDING_CURSE);
+                        if (isVanish || isBind) {
+                            event.getEntity().getInventory().setItemInOffHand(null);
+                            if ((isVanish && vanish == ISettings.KeepInvPolicy.DROP) || (isBind && bind == ISettings.KeepInvPolicy.DROP)) {
+                                if (!event.getDrops().contains(stack)) {
+                                    event.getDrops().add(stack);
+                                }
+                            }
+                        }
+                    }
+                }
             }
         }
     }

Essentials/src/main/java/com/earth2me/essentials/craftbukkit/InventoryWorkaround.java

@@ -1,5 +1,6 @@
 package com.earth2me.essentials.craftbukkit;
 
+import com.earth2me.essentials.utils.VersionUtil;
 import org.bukkit.Bukkit;
 import org.bukkit.Material;
 import org.bukkit.entity.Player;
@@ -15,15 +16,13 @@ import java.util.Map;
 /*
  * This class can be removed when https://github.com/Bukkit/CraftBukkit/pull/193 is accepted to CraftBukkit
  */
-
 public final class InventoryWorkaround {
     /*
     Spigot 1.9, for whatever reason, decided to merge the armor and main player inventories without providing a way
     to access the main inventory. There's lots of ugly code in here to work around that.
      */
     private static final int USABLE_PLAYER_INV_SIZE = 36;
-    // Hot-ish code so cache
+    private static final boolean IS_OFFHAND = VersionUtil.getServerBukkitVersion().isHigherThanOrEqualTo(VersionUtil.v1_9_R01);
-    private static Boolean hasMainHandSupport = null;
 
     private InventoryWorkaround() {
     }
@@ -201,87 +200,45 @@ public final class InventoryWorkaround {
 
     @SuppressWarnings("deprecation")
     public static void setItemInMainHand(final Player p, final ItemStack item) {
-        if (hasMainHandSupport == null) {
+        if (IS_OFFHAND) {
-            try {
-                p.getInventory().setItemInMainHand(item);
-                hasMainHandSupport = true;
-            } catch (final Throwable e) {
-                p.setItemInHand(item);
-                hasMainHandSupport = false;
-            }
-        } else {
-            if (hasMainHandSupport) {
             p.getInventory().setItemInMainHand(item);
         } else {
             p.setItemInHand(item);
         }
     }
-    }
 
     @SuppressWarnings("deprecation")
     public static void setItemInMainHand(final EntityEquipment invent, final ItemStack item) {
-        if (hasMainHandSupport == null) {
+        if (IS_OFFHAND) {
-            try {
-                invent.setItemInMainHand(item);
-                hasMainHandSupport = true;
-            } catch (final Throwable e) {
-                invent.setItemInHand(item);
-                hasMainHandSupport = false;
-            }
-        } else {
-            if (hasMainHandSupport) {
             invent.setItemInMainHand(item);
         } else {
             invent.setItemInHand(item);
         }
     }
-    }
 
     @SuppressWarnings("deprecation")
     public static void setItemInMainHandDropChance(final EntityEquipment invent, final float chance) {
-        if (hasMainHandSupport == null) {
+        if (IS_OFFHAND) {
-            try {
-                invent.setItemInMainHandDropChance(chance);
-                hasMainHandSupport = true;
-            } catch (final Throwable e) {
-                invent.setItemInHandDropChance(chance);
-                hasMainHandSupport = false;
-            }
-        } else {
-            if (hasMainHandSupport) {
             invent.setItemInMainHandDropChance(chance);
         } else {
             invent.setItemInHandDropChance(chance);
         }
     }
-    }
 
     public static void setItemInOffHand(final Player p, final ItemStack item) {
-        // This assumes that all builds that support a main hand also support an off hand.
+        if (IS_OFFHAND) {
-        if (hasMainHandSupport == null || hasMainHandSupport) {
-            try {
             p.getInventory().setItemInOffHand(item);
-                hasMainHandSupport = true;
-            } catch (final Throwable e) {
-                hasMainHandSupport = false;
-            }
         }
     }
 
     public static int clearItemInOffHand(final Player p, final ItemStack item) {
-        // This should be added because if `/clear` itself is not initilized it will return an Error: null.
+        if (IS_OFFHAND) {
-        if (hasMainHandSupport == null || hasMainHandSupport) {
-            try {
             int removedAmount = 0;
             if (p.getInventory().getItemInOffHand().getType().equals(item.getType())) {
                 removedAmount = p.getInventory().getItemInOffHand().getAmount();
                 p.getInventory().setItemInOffHand(null);
             }
-                hasMainHandSupport = true;
             return removedAmount;
-            } catch (final Throwable e) {
-                hasMainHandSupport = false;
-            }
         }
         return 0;
     }