GDScript: Fix object iterator opcodes

modules/gdscript/tests/scripts/runtime/features/object_iterators.gd

@@ -0,0 +1,49 @@
+class MyIterator:
+	var count: int
+
+	func _init(p_count: int) -> void:
+		count = p_count
+
+	func _iter_init(arg: Array) -> bool:
+		prints("_iter_init", arg)
+		arg[0] = 0
+		return arg[0] < count
+
+	func _iter_next(arg: Array) -> bool:
+		prints("_iter_next", arg)
+		arg[0] += 1
+		return arg[0] < count
+
+	func _iter_get(arg: Variant) -> Variant:
+		prints("_iter_get", arg)
+		return arg
+
+func test():
+	var container := PackedDataContainer.new()
+	var _err := container.pack([{
+		id = 123,
+		node_path = ^"/some/path",
+		data = PackedByteArray(),
+	}])
+
+	for ref: PackedDataContainerRef in container:
+		for key: String in ref:
+			print(key)
+
+	print("===")
+
+	for ref: Variant in container:
+		for key: String in ref:
+			print(key)
+
+	print("===")
+
+	var hard_custom := MyIterator.new(3)
+	for x in hard_custom:
+		print(x)
+
+	print("===")
+
+	var weak_custom: Variant = MyIterator.new(3)
+	for x in weak_custom:
+		print(x)