From 6f6c2dc53b1139ff47f55219c8f8e6fe2079c1f7 Mon Sep 17 00:00:00 2001
From: A Thousand Ships <96648715+AThousandShips@users.noreply.github.com>
Date: Mon, 8 Jan 2024 19:55:03 +0100
Subject: [PATCH] [GDScript] Fix lifetime of call base object

Ensures that the lifetime of an `Object` outlasts calls to it

Also adds a check to `Object::~Object()` to check for locked state
---
 core/object/object.cpp                        |  4 +++
 modules/gdscript/gdscript_compiler.cpp        | 16 ++++++++++++
 .../runtime/features/ref_counted_lifetime.gd  | 26 +++++++++++++++++++
 .../runtime/features/ref_counted_lifetime.out |  1 +
 4 files changed, 47 insertions(+)
 create mode 100644 modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.gd
 create mode 100644 modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.out

diff --git a/core/object/object.cpp b/core/object/object.cpp
index cbf1da79fde9..60d98e9c0f0b 100644
--- a/core/object/object.cpp
+++ b/core/object/object.cpp
@@ -2105,6 +2105,10 @@ void Object::detach_from_objectdb() {
 }
 
 Object::~Object() {
+#ifdef DEBUG_ENABLED
+	CRASH_COND_MSG(_lock_index.get() != 1, "TODO message for object.");
+#endif // DEBUG_ENABLED
+
 	if (script_instance) {
 		memdelete(script_instance);
 	}
diff --git a/modules/gdscript/gdscript_compiler.cpp b/modules/gdscript/gdscript_compiler.cpp
index 99dedabd847d..cd0fbcb124fd 100644
--- a/modules/gdscript/gdscript_compiler.cpp
+++ b/modules/gdscript/gdscript_compiler.cpp
@@ -708,11 +708,27 @@ GDScriptCodeGenerator::Address GDScriptCompiler::_parse_expression(CodeGen &code
 											gen->write_call_method_bind(result, base, method, arguments);
 										}
 									} else {
+										// Make temporary if member variable and ref-counted.
+										if (ClassDB::is_parent_class(class_name, "RefCounted") && base.mode == GDScriptCodeGenerator::Address::MEMBER) {
+											GDScriptCodeGenerator::Address temp = codegen.add_temporary(base.type);
+											gen->write_assign(temp, base);
+
+											base = temp;
+										}
+
 										gen->write_call(result, base, call->function_name, arguments);
 									}
 								} else if (base.type.has_type && base.type.kind == GDScriptDataType::BUILTIN) {
 									gen->write_call_builtin_type(result, base, base.type.builtin_type, call->function_name, arguments);
 								} else {
+									// Make temporary if member variable.
+									if (base.mode == GDScriptCodeGenerator::Address::MEMBER) {
+										GDScriptCodeGenerator::Address temp = codegen.add_temporary(base.type);
+										gen->write_assign(temp, base);
+
+										base = temp;
+									}
+
 									gen->write_call(result, base, call->function_name, arguments);
 								}
 								if (base.mode == GDScriptCodeGenerator::Address::TEMPORARY) {
diff --git a/modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.gd b/modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.gd
new file mode 100644
index 000000000000..c9d29370d019
--- /dev/null
+++ b/modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.gd
@@ -0,0 +1,26 @@
+# https://github.com/godotengine/godot/issues/86788
+
+extends Node
+
+class MyClassTyped:
+	func enter(outer):
+		outer.my_class_typed = MyClassTyped.new()
+		exit()
+
+	func exit():
+		pass
+
+class MyClassUnTyped:
+	func enter(outer):
+		outer.my_class_untyped = MyClassUnTyped.new()
+		exit()
+
+	func exit():
+		pass
+
+var my_class_typed := MyClassTyped.new()
+var my_class_untyped = MyClassUnTyped.new()
+
+func test():
+	my_class_typed.enter(self)
+	my_class_untyped.enter(self)
diff --git a/modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.out b/modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.out
new file mode 100644
index 000000000000..d73c5eb7cde3
--- /dev/null
+++ b/modules/gdscript/tests/scripts/runtime/features/ref_counted_lifetime.out
@@ -0,0 +1 @@
+GDTEST_OK