Fixed concurrent modification exception when using the ice spell. #90

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/IceSpell.java

@@ -1,5 +1,7 @@
 package com.minelittlepony.unicopia.ability.magic.spell.effect;
 
+import java.util.List;
+
 import com.minelittlepony.unicopia.ability.magic.Caster;
 import com.minelittlepony.unicopia.ability.magic.spell.Situation;
 import com.minelittlepony.unicopia.ability.magic.spell.trait.SpellTraits;
@@ -70,10 +72,13 @@ public class IceSpell extends AbstractSpell {
     }
 
     protected boolean applyEntities(Caster<?> source, Vec3d pos) {
-        return !VecHelper.findInRange(source.asEntity(), source.asWorld(), pos, 3, i -> applyEntitySingle(source, i)).isEmpty();
+        List<Entity> entities = VecHelper.findInRange(source.asEntity(), source.asWorld(), pos, 3);
+        entities.forEach(entity -> applyEntitySingle(source, entity));
+        return !entities.isEmpty();
+
     }
 
-    protected boolean applyEntitySingle(Caster<?> source, Entity e) {
+    protected void applyEntitySingle(Caster<?> source, Entity e) {
         if (e instanceof TntEntity) {
             e.remove(RemovalReason.DISCARDED);
             e.getEntityWorld().setBlockState(e.getBlockPos(), Blocks.TNT.getDefaultState());
@@ -82,8 +87,6 @@ public class IceSpell extends AbstractSpell {
         } else {
             e.damage(MagicalDamageSource.create("cold", source.getMaster()), 2);
         }
-
-        return true;
     }
 
     private boolean applyBlockSingle(Entity owner, World world, BlockPos pos, Situation situation) {

src/main/java/com/minelittlepony/unicopia/ability/magic/spell/effect/SiphoningSpell.java

@@ -1,6 +1,7 @@
 package com.minelittlepony.unicopia.ability.magic.spell.effect;
 
 import java.util.List;
+import java.util.function.Predicate;
 import java.util.stream.Collectors;
 import java.util.stream.Stream;
 
@@ -20,6 +21,7 @@ import com.minelittlepony.unicopia.util.MagicalDamageSource;
 import com.minelittlepony.unicopia.util.VecHelper;
 import com.minelittlepony.unicopia.util.shape.Sphere;
 
+import net.minecraft.entity.Entity;
 import net.minecraft.entity.LivingEntity;
 import net.minecraft.entity.damage.DamageSource;
 import net.minecraft.entity.player.PlayerEntity;
@@ -33,6 +35,7 @@ import net.minecraft.util.math.Vec3d;
  * A spell that pulls health from other entities and delivers it to the caster.
  */
 public class SiphoningSpell extends AbstractAreaEffectSpell {
+    static final Predicate<Entity> TARGET_PREDICATE = EntityPredicates.EXCEPT_CREATIVE_OR_SPECTATOR.and(EntityPredicates.VALID_LIVING_ENTITY);
 
     private int ticksUpset;
 
@@ -80,9 +83,7 @@ public class SiphoningSpell extends AbstractAreaEffectSpell {
     }
 
     private Stream<LivingEntity> getTargets(Caster<?> source) {
-        return VecHelper.findInRange(null, source.asWorld(), source.getOriginVector(), 4 + source.getLevel().getScaled(6), EntityPredicates.EXCEPT_CREATIVE_OR_SPECTATOR.and(e -> e instanceof LivingEntity))
-                .stream()
-                .map(e -> (LivingEntity)e);
+        return VecHelper.findInRange(null, source.asWorld(), source.getOriginVector(), 4 + source.getLevel().getScaled(6), TARGET_PREDICATE).stream().map(e -> (LivingEntity)e);
     }
 
     private void distributeHealth(Caster<?> source) {

src/main/java/com/minelittlepony/unicopia/item/CrystalHeartItem.java

@@ -1,6 +1,7 @@
 package com.minelittlepony.unicopia.item;
 
 import java.util.*;
+import java.util.function.Predicate;
 import java.util.function.Supplier;
 
 import com.google.common.base.Suppliers;
@@ -31,6 +32,7 @@ import net.minecraft.util.math.Vec3d;
 import net.minecraft.world.World;
 
 public class CrystalHeartItem extends Item implements FloatingArtefactEntity.Artifact {
+    static final Predicate<Entity> TARGET_PREDICATE = EntityPredicates.EXCEPT_CREATIVE_OR_SPECTATOR.and(EntityPredicates.VALID_ENTITY).and(e -> (e instanceof PlayerEntity || e instanceof MobEntity));
     private static final Supplier<Map<Item, Item>> ITEM_MAP = Suppliers.memoize(() -> {
         return Map.of(
                 Items.BUCKET, UItems.LOVE_BUCKET,
@@ -115,7 +117,7 @@ public class CrystalHeartItem extends Item implements FloatingArtefactEntity.Art
                 List<LivingEntity> outputs = new ArrayList<>();
                 List<ItemEntity> containers = new ArrayList<>();
 
-                VecHelper.findInRange(entity, entity.world, entity.getPos(), 20, EntityPredicates.EXCEPT_CREATIVE_OR_SPECTATOR.and(e -> !e.isRemoved() && (e instanceof PlayerEntity || e instanceof MobEntity))).forEach(e -> {
+                VecHelper.findInRange(entity, entity.world, entity.getPos(), 20, TARGET_PREDICATE).forEach(e -> {
                     LivingEntity living = (LivingEntity)e;
 
                     if (e instanceof PlayerEntity

src/main/java/com/minelittlepony/unicopia/util/VecHelper.java

@@ -32,4 +32,9 @@ public interface VecHelper {
         double diameter = radius * 2;
         return w.getOtherEntities(origin, Box.of(pos, diameter, diameter, diameter), predicate == null ? inRange(pos, radius) : inRange(pos, radius).and(predicate));
     }
+
+    static List<Entity> findInRange(@Nullable Entity origin, EntityView w, Vec3d pos, double radius) {
+        double diameter = radius * 2;
+        return w.getOtherEntities(origin, Box.of(pos, diameter, diameter, diameter), inRange(pos, radius));
+    }
 }