Merge pull request #119634 from shiena/android-fix-proxy-equals-infinite-recursion

Android: Fix infinite recursion in proxy equals handler

platform/android/java/lib/src/main/java/org/godotengine/godot/plugin/AndroidRuntimePlugin.kt

@@ -81,7 +81,7 @@ class AndroidRuntimePlugin(godot: Godot) : GodotPlugin(godot) {
 					// We automatically handle 'toString', 'equals' and 'hashCode' to simplify the task of the caller
 					// and provide consistency.
 					"toString" -> "Godot Callable Proxy for $interfaceName"
-					"equals" -> proxy == args[0]
+					"equals" -> proxy === args[0]
 					"hashCode" -> godotCallable.hashCode()
 
 					// Invocation for the interface single abstract method falls here and is dispatched to the
@@ -106,8 +106,8 @@ class AndroidRuntimePlugin(godot: Godot) : GodotPlugin(godot) {
 					// We automatically handle 'toString', 'equals' and 'hashCode' to simplify the task of the caller
 					// and provide consistency.
 					"toString" -> "Godot Object Proxy for ${interfaces.joinToString(",")}"
-					"equals" -> proxy == args[0]
-					"hashCode" -> godotObjectID
+					"equals" -> proxy === args[0]
+					"hashCode" -> godotObjectID.hashCode()
 
 					// Invocation for the remaining interface(s) methods falls here and is dispatched to the
 					// Godot Object.

platform/android/java/lib/src/test/java/org/godotengine/godot/plugin/AndroidRuntimePluginTest.kt

@@ -0,0 +1,131 @@
+/**************************************************************************/
+/*  AndroidRuntimePluginTest.kt                                           */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+package org.godotengine.godot.plugin
+
+import org.godotengine.godot.variant.Callable
+import org.junit.Assert.assertEquals
+import org.junit.Assert.assertFalse
+import org.junit.Assert.assertNotNull
+import org.junit.Assert.assertTrue
+import org.junit.Test
+
+class AndroidRuntimePluginTest {
+
+	private val createProxyFromGodotCallable = AndroidRuntimePlugin::class.java
+		.getDeclaredMethod("createProxyFromGodotCallable", String::class.java, Callable::class.java)
+		.apply { isAccessible = true }
+
+	private val createProxyFromGodotObjectID = AndroidRuntimePlugin::class.java
+		.getDeclaredMethod("createProxyFromGodotObjectID", Long::class.javaPrimitiveType, Array<String>::class.java)
+		.apply { isAccessible = true }
+
+	private fun newCallable(): Callable {
+		val ctor = Callable::class.java.getDeclaredConstructor(Long::class.javaPrimitiveType)
+		ctor.isAccessible = true
+		return ctor.newInstance(0L)
+	}
+
+	private fun callableProxy(): Any {
+		val proxy = createProxyFromGodotCallable.invoke(null, Runnable::class.java.name, newCallable())
+		assertNotNull(proxy)
+		return proxy!!
+	}
+
+	private fun objectIDProxy(godotObjectID: Long = 0L): Any {
+		val proxy = createProxyFromGodotObjectID.invoke(null, godotObjectID, arrayOf(Runnable::class.java.name))
+		assertNotNull(proxy)
+		return proxy!!
+	}
+
+	// Regression tests for the infinite recursion in the proxy equals handler.
+	// Kotlin's `proxy == args[0]` compiles to `proxy.equals(args[0])`, which the
+	// JDK proxy dispatches back through the InvocationHandler — the previous
+	// implementation hit the same branch and recursed into StackOverflowError.
+
+	@Test
+	fun `Given Callable proxy, When equals is invoked with itself, Then returns true without recursion`() {
+		val proxy = callableProxy()
+		assertTrue(proxy.equals(proxy))
+	}
+
+	@Test
+	fun `Given Callable proxy, When equals is invoked with another instance, Then returns false without recursion`() {
+		val proxy = callableProxy()
+		val otherProxy = callableProxy()
+		assertFalse(proxy.equals(otherProxy))
+		assertFalse(proxy.equals(Any()))
+		assertFalse(proxy.equals(null))
+	}
+
+	@Test
+	fun `Given ObjectID proxy, When equals is invoked with itself, Then returns true without recursion`() {
+		val proxy = objectIDProxy()
+		assertTrue(proxy.equals(proxy))
+	}
+
+	@Test
+	fun `Given ObjectID proxy, When equals is invoked with another instance, Then returns false without recursion`() {
+		val proxy = objectIDProxy()
+		val otherProxy = objectIDProxy()
+		assertFalse(proxy.equals(otherProxy))
+		assertFalse(proxy.equals(Any()))
+		assertFalse(proxy.equals(null))
+	}
+
+	// Sanity checks that the proxy's toString / hashCode handlers still operate
+	// as documented and that they do not get caught up in the equals fix.
+
+	@Test
+	fun `Given Callable proxy, When toString is invoked, Then returns the documented label`() {
+		val proxy = callableProxy()
+		assertEquals("Godot Callable Proxy for ${Runnable::class.java.name}", proxy.toString())
+	}
+
+	@Test
+	fun `Given ObjectID proxy, When toString is invoked, Then returns the documented label`() {
+		val proxy = objectIDProxy()
+		assertEquals("Godot Object Proxy for ${Runnable::class.java.name}", proxy.toString())
+	}
+
+	@Test
+	fun `Given Callable proxy, When hashCode is invoked, Then returns the Callable hashCode`() {
+		val callable = newCallable()
+		val proxy = createProxyFromGodotCallable.invoke(null, Runnable::class.java.name, callable)!!
+		assertEquals(callable.hashCode(), proxy.hashCode())
+	}
+
+	@Test
+	fun `Given ObjectID proxy, When hashCode is invoked, Then returns the ObjectID hashCode`() {
+		val godotObjectID = 0x1_0000_002AL
+		val proxy = objectIDProxy(godotObjectID)
+		assertEquals(godotObjectID.hashCode(), proxy.hashCode())
+	}
+}