From db9e3f257f6f5eebb36db802ac6d9f137cfcb9a4 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Pedro=20J=2E=20Est=C3=A9banez?= <pedrojrulez@gmail.com>
Date: Sun, 21 Feb 2021 03:03:07 +0100
Subject: [PATCH] Rationalize property reversion

---
 editor/editor_inspector.cpp | 131 ++++++++++++++++--------------------
 editor/editor_inspector.h   |   2 +
 2 files changed, 59 insertions(+), 74 deletions(-)

diff --git a/editor/editor_inspector.cpp b/editor/editor_inspector.cpp
index 3db03c02761..4a3413d9efa 100644
--- a/editor/editor_inspector.cpp
+++ b/editor/editor_inspector.cpp
@@ -493,6 +493,7 @@ bool EditorPropertyRevert::is_node_property_different(Node *p_node, const Varian
 
 			if (ss.is_valid()) {
 				found_state = true;
+				break;
 			}
 			if (node == edited_scene) {
 				//just in case
@@ -506,59 +507,71 @@ bool EditorPropertyRevert::is_node_property_different(Node *p_node, const Varian
 		}
 	}
 
-	if (p_current.get_type() == Variant::FLOAT && p_orig.get_type() == Variant::FLOAT) {
-		float a = p_current;
-		float b = p_orig;
-
-		return !Math::is_equal_approx(a, b); //this must be done because, as some scenes save as text, there might be a tiny difference in floats due to numerical error
-	}
-
-	return bool(Variant::evaluate(Variant::OP_NOT_EQUAL, p_current, p_orig));
+	return is_property_value_different(p_current, p_orig);
 }
 
-bool EditorPropertyRevert::can_property_revert(Object *p_object, const StringName &p_property) {
-	bool has_revert = false;
-
-	Node *node = Object::cast_to<Node>(p_object);
-
-	if (node && EditorPropertyRevert::may_node_be_in_instance(node)) {
-		//check for difference including instantiation
-		Variant vorig;
-		if (EditorPropertyRevert::get_instantiated_node_original_property(node, p_property, vorig)) {
-			Variant v = p_object->get(p_property);
-
-			if (EditorPropertyRevert::is_node_property_different(node, v, vorig)) {
-				has_revert = true;
-			}
-		}
+bool EditorPropertyRevert::is_property_value_different(const Variant &p_a, const Variant &p_b) {
+	if (p_a.get_type() == Variant::FLOAT && p_b.get_type() == Variant::FLOAT) {
+		//this must be done because, as some scenes save as text, there might be a tiny difference in floats due to numerical error
+		return !Math::is_equal_approx((float)p_a, (float)p_b);
 	} else {
-		//check for difference against default class value instead
-		Variant default_value = ClassDB::class_get_default_property_value(p_object->get_class_name(), p_property);
-		if (default_value != Variant() && default_value != p_object->get(p_property)) {
-			has_revert = true;
-		}
+		return p_a != p_b;
 	}
+}
 
+Variant EditorPropertyRevert::get_property_revert_value(Object *p_object, const StringName &p_property) {
 	// If the object implements property_can_revert, rely on that completely
 	// (i.e. don't then try to revert to default value - the property_get_revert implementation
 	// can do that if so desired)
-	if (p_object->has_method("property_can_revert")) {
-		has_revert = p_object->call("property_can_revert", p_property).operator bool();
-	} else {
-		if (!has_revert && !p_object->get_script().is_null()) {
-			Ref<Script> scr = p_object->get_script();
-			if (scr.is_valid()) {
-				Variant orig_value;
-				if (scr->get_property_default_value(p_property, orig_value)) {
-					if (orig_value != p_object->get(p_property)) {
-						has_revert = true;
-					}
+	if (p_object->has_method("property_can_revert") && p_object->call("property_can_revert", p_property)) {
+		return p_object->call("property_get_revert", p_property);
+	}
+
+	Ref<Script> scr = p_object->get_script();
+	Node *node = Object::cast_to<Node>(p_object);
+	if (node && EditorPropertyRevert::may_node_be_in_instance(node)) {
+		//if this node is an instance or inherits, but it has a script attached which is unrelated
+		//to the one set for the parent and also has a default value for the property, consider that
+		//has precedence over the value from the parent, because that is an explicit source of defaults
+		//closer in the tree to the current node
+		bool ignore_parent = false;
+		if (scr.is_valid()) {
+			Variant sorig;
+			if (EditorPropertyRevert::get_instantiated_node_original_property(node, "script", sorig) && !scr->inherits_script(sorig)) {
+				Variant dummy;
+				if (scr->get_property_default_value(p_property, dummy)) {
+					ignore_parent = true;
 				}
 			}
 		}
+
+		if (!ignore_parent) {
+			//check for difference including instantiation
+			Variant vorig;
+			if (EditorPropertyRevert::get_instantiated_node_original_property(node, p_property, vorig)) {
+				return vorig;
+			}
+		}
 	}
 
-	return has_revert;
+	if (scr.is_valid()) {
+		Variant orig_value;
+		if (scr->get_property_default_value(p_property, orig_value)) {
+			return orig_value;
+		}
+	}
+
+	//report default class value instead
+	return ClassDB::class_get_default_property_value(p_object->get_class_name(), p_property);
+}
+
+bool EditorPropertyRevert::can_property_revert(Object *p_object, const StringName &p_property) {
+	Variant revert_value = EditorPropertyRevert::get_property_revert_value(p_object, p_property);
+	if (revert_value.get_type() == Variant::NIL) {
+		return false;
+	}
+	Variant current_value = p_object->get(p_property);
+	return EditorPropertyRevert::is_property_value_different(current_value, revert_value);
 }
 
 void EditorProperty::update_reload_status() {
@@ -761,41 +774,11 @@ void EditorProperty::_gui_input(const Ref<InputEvent> &p_event) {
 		}
 
 		if (revert_rect.has_point(mpos)) {
-			Variant vorig;
-
-			Node *node = Object::cast_to<Node>(object);
-			if (node && EditorPropertyRevert::may_node_be_in_instance(node) && EditorPropertyRevert::get_instantiated_node_original_property(node, property, vorig)) {
-				emit_changed(property, vorig.duplicate(true));
-				update_property();
-				return;
-			}
-
-			if (object->call("property_can_revert", property).operator bool()) {
-				Variant rev = object->call("property_get_revert", property);
-				emit_changed(property, rev);
-				update_property();
-				return;
-			}
-
-			if (!object->get_script().is_null()) {
-				Ref<Script> scr = object->get_script();
-				if (scr.is_valid()) {
-					Variant orig_value;
-					if (scr->get_property_default_value(property, orig_value)) {
-						emit_changed(property, orig_value);
-						update_property();
-						return;
-					}
-				}
-			}
-
-			Variant default_value = ClassDB::class_get_default_property_value(object->get_class_name(), property);
-			if (default_value != Variant()) {
-				emit_changed(property, default_value);
-				update_property();
-				return;
-			}
+			Variant revert_value = EditorPropertyRevert::get_property_revert_value(object, property);
+			emit_changed(property, revert_value);
+			update_property();
 		}
+
 		if (check_rect.has_point(mpos)) {
 			checked = !checked;
 			update();
diff --git a/editor/editor_inspector.h b/editor/editor_inspector.h
index ee70bd4397e..2bb856dc81b 100644
--- a/editor/editor_inspector.h
+++ b/editor/editor_inspector.h
@@ -42,6 +42,8 @@ public:
 	static bool may_node_be_in_instance(Node *p_node);
 	static bool get_instantiated_node_original_property(Node *p_node, const StringName &p_prop, Variant &value);
 	static bool is_node_property_different(Node *p_node, const Variant &p_current, const Variant &p_orig);
+	static bool is_property_value_different(const Variant &p_a, const Variant &p_b);
+	static Variant get_property_revert_value(Object *p_object, const StringName &p_property);
 
 	static bool can_property_revert(Object *p_object, const StringName &p_property);
 };