SPIGOT-4815: Location.equals() not working

By: md_5 <git@md-5.net>

paper-api/src/main/java/org/bukkit/Location.java

@@ -543,7 +543,9 @@ public class Location implements Cloneable, ConfigurationSerializable {
         }
         final Location other = (Location) obj;
 
-        if (this.world != other.world && (this.world == null || !this.world.equals(other.world))) {
+        World world = (this.world == null) ? null : this.world.get();
+        World otherWorld = (other.world == null) ? null : other.world.get();
+        if (world != otherWorld && (world == null || !world.equals(otherWorld))) {
             return false;
         }
         if (Double.doubleToLongBits(this.x) != Double.doubleToLongBits(other.x)) {
@@ -568,7 +570,7 @@ public class Location implements Cloneable, ConfigurationSerializable {
     public int hashCode() {
         int hash = 3;
 
-        World world = (this.world == null) ? null : getWorld();
+        World world = (this.world == null) ? null : this.world.get();
         hash = 19 * hash + (world != null ? world.hashCode() : 0);
         hash = 19 * hash + (int) (Double.doubleToLongBits(this.x) ^ (Double.doubleToLongBits(this.x) >>> 32));
         hash = 19 * hash + (int) (Double.doubleToLongBits(this.y) ^ (Double.doubleToLongBits(this.y) >>> 32));
@@ -580,7 +582,7 @@ public class Location implements Cloneable, ConfigurationSerializable {
 
     @Override
     public String toString() {
-        World world = (this.world == null) ? null : getWorld();
+        World world = (this.world == null) ? null : this.world.get();
         return "Location{" + "world=" + world + ",x=" + x + ",y=" + y + ",z=" + z + ",pitch=" + pitch + ",yaw=" + yaw + '}';
     }
 

paper-api/src/test/java/org/bukkit/LocationTest.java

@@ -176,12 +176,21 @@ public class LocationTest {
         assertThat(vector.getZ(), is(closeTo(z, delta)));
     }
 
+    @Test
+    public void testEquals() {
+        Location first = getLocation().add(getVector());
+        Location second = getLocation().add(getVector());
+
+        assertThat(first.hashCode(), is(second.hashCode()));
+        assertThat(first, is(second));
+    }
+
     private Vector getVector() {
         return new Vector(x, y, z);
     }
 
     private static Location getEmptyLocation() {
-        return new Location(null, 0, 0, 0);
+        return new Location(TestWorld.INSTANCE, 0, 0, 0);
     }
 
     private Location getLocation() {

paper-api/src/test/java/org/bukkit/TestWorld.java

@@ -0,0 +1,64 @@
+package org.bukkit;
+
+import com.google.common.collect.ImmutableMap;
+import java.lang.reflect.InvocationHandler;
+import java.lang.reflect.Method;
+import java.lang.reflect.Proxy;
+import java.util.Map;
+
+public final class TestWorld implements InvocationHandler {
+
+    private static interface MethodHandler {
+
+        Object handle(TestWorld server, Object[] args);
+    }
+
+    private static final Map<Method, MethodHandler> methods;
+    public static final World INSTANCE;
+
+    static {
+        try {
+            ImmutableMap.Builder<Method, MethodHandler> methodMap = ImmutableMap.builder();
+            methodMap.put(
+                    Object.class.getMethod("equals", Object.class),
+                    new MethodHandler() {
+                        @Override
+                        public Object handle(TestWorld server, Object[] args) {
+                            return this == args[0];
+                        }
+                    }
+                );
+            methodMap.put(
+                    Object.class.getMethod("hashCode"),
+                    new MethodHandler() {
+                        @Override
+                        public Object handle(TestWorld server, Object[] args) {
+                            return this.hashCode();
+                        }
+                    }
+                );
+            methods = methodMap.build();
+
+            TestWorld world = new TestWorld();
+            INSTANCE = Proxy.getProxyClass(World.class.getClassLoader(), World.class).asSubclass(World.class).getConstructor(InvocationHandler.class).newInstance(world);
+        } catch (Throwable t) {
+            throw new Error(t);
+        }
+    }
+
+    private TestWorld() {
+    }
+
+    public static Server getInstance() {
+        return Bukkit.getServer();
+    }
+
+    @Override
+    public Object invoke(Object proxy, Method method, Object[] args) {
+        MethodHandler handler = methods.get(method);
+        if (handler != null) {
+            return handler.handle(this, args);
+        }
+        throw new UnsupportedOperationException(String.valueOf(method));
+    }
+}