From 924c2078dae69e73032af04e96200f44187d2c8d Mon Sep 17 00:00:00 2001
From: Zae <zaevi@live.com>
Date: Fri, 22 Oct 2021 19:44:38 +0800
Subject: [PATCH] Fix unexpected crashes in `notification`

---
 scene/2d/collision_polygon_2d.cpp |  1 +
 scene/2d/collision_shape_2d.cpp   |  2 ++
 scene/2d/ray_cast_2d.cpp          |  1 +
 scene/gui/control.cpp             | 12 +++++++++---
 4 files changed, 13 insertions(+), 3 deletions(-)

diff --git a/scene/2d/collision_polygon_2d.cpp b/scene/2d/collision_polygon_2d.cpp
index 271a4da705b..00bfa62449c 100644
--- a/scene/2d/collision_polygon_2d.cpp
+++ b/scene/2d/collision_polygon_2d.cpp
@@ -131,6 +131,7 @@ void CollisionPolygon2D::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_DRAW: {
+			ERR_FAIL_COND(!is_inside_tree());
 			if (!Engine::get_singleton()->is_editor_hint() && !get_tree()->is_debugging_collisions_hint()) {
 				break;
 			}
diff --git a/scene/2d/collision_shape_2d.cpp b/scene/2d/collision_shape_2d.cpp
index 54cb851216b..c7742c7ba57 100644
--- a/scene/2d/collision_shape_2d.cpp
+++ b/scene/2d/collision_shape_2d.cpp
@@ -88,6 +88,8 @@ void CollisionShape2D::_notification(int p_what) {
 
 		} break;
 		case NOTIFICATION_DRAW: {
+			ERR_FAIL_COND(!is_inside_tree());
+
 			if (!Engine::get_singleton()->is_editor_hint() && !get_tree()->is_debugging_collisions_hint()) {
 				break;
 			}
diff --git a/scene/2d/ray_cast_2d.cpp b/scene/2d/ray_cast_2d.cpp
index 3ac2128c2eb..0a8e9e2a58b 100644
--- a/scene/2d/ray_cast_2d.cpp
+++ b/scene/2d/ray_cast_2d.cpp
@@ -157,6 +157,7 @@ void RayCast2D::_notification(int p_what) {
 		} break;
 
 		case NOTIFICATION_DRAW: {
+			ERR_FAIL_COND(!is_inside_tree());
 			if (!Engine::get_singleton()->is_editor_hint() && !get_tree()->is_debugging_collisions_hint()) {
 				break;
 			}
diff --git a/scene/gui/control.cpp b/scene/gui/control.cpp
index 973074397b6..e4048fbf091 100644
--- a/scene/gui/control.cpp
+++ b/scene/gui/control.cpp
@@ -637,7 +637,9 @@ void Control::_notification(int p_notification) {
 				}
 			} else {
 				//is a regular root control or top_level
-				data.RI = get_viewport()->_gui_add_root_control(this);
+				Viewport *viewport = get_viewport();
+				ERR_FAIL_COND(!viewport);
+				data.RI = viewport->_gui_add_root_control(this);
 			}
 
 			data.parent_canvas_item = get_parent_item();
@@ -646,7 +648,9 @@ void Control::_notification(int p_notification) {
 				data.parent_canvas_item->connect("item_rect_changed", callable_mp(this, &Control::_size_changed));
 			} else {
 				//connect viewport
-				get_viewport()->connect("size_changed", callable_mp(this, &Control::_size_changed));
+				Viewport *viewport = get_viewport();
+				ERR_FAIL_COND(!viewport);
+				viewport->connect("size_changed", callable_mp(this, &Control::_size_changed));
 			}
 		} break;
 		case NOTIFICATION_EXIT_CANVAS: {
@@ -655,7 +659,9 @@ void Control::_notification(int p_notification) {
 				data.parent_canvas_item = nullptr;
 			} else if (!is_set_as_top_level()) {
 				//disconnect viewport
-				get_viewport()->disconnect("size_changed", callable_mp(this, &Control::_size_changed));
+				Viewport *viewport = get_viewport();
+				ERR_FAIL_COND(!viewport);
+				viewport->disconnect("size_changed", callable_mp(this, &Control::_size_changed));
 			}
 
 			if (data.RI) {