[Editor] Prevent deferred tooltip update crash

[AThousandShips]

Caused by TreeItems being accessed after clearing the tree on reset.

Can largely confirm this at least on 4.3, though without debug symbols I'm not sure if it is the same issue, can't reliably on 4.2, but hard to tell exactly why. I can reliably trigger it on debug builds, and with a few scenes in 4.4.beta3

Considered using ObjectID but I think this is a case where things should be solved by catching the problem at the source. This might still occur in edge cases where the timer fires during other updates, but this at least solves the issue reliably for me.

To trigger this bug:

• Open several scenes
• Edit the editor description of one of the root nodes
• Switch quickly between the tabs

The editor should crash, caused by various errors of memory access related to TreeItem nodes, this would be because the deferred tooltip update holding a reference to a now freed TreeItem, relevant code is:

godot/editor/gui/scene_tree_editor.cpp

Lines 642 to 650 in 261e7d3

	void SceneTreeEditor::_queue_update_node_tooltip(Node *p_node, TreeItem *p_item) {
	Callable update_tooltip = callable_mp(this, &SceneTreeEditor::_update_node_tooltip);
	if (update_node_tooltip_delay->is_connected("timeout", update_tooltip)) {
	update_node_tooltip_delay->disconnect("timeout", update_tooltip);
	}
	update_node_tooltip_delay->connect("timeout", update_tooltip.bind(p_node, p_item));
	update_node_tooltip_delay->start();
	}

Where the timer set up, and:

godot/editor/gui/scene_tree_editor.cpp

Lines 657 to 667 in 261e7d3

	if (p_node == get_scene_node() && p_node->get_scene_inherited_state().is_valid()) {
	if (p_item->get_button_by_id(0, BUTTON_SUBSCENE) == -1) {
	p_item->add_button(0, get_editor_theme_icon(SNAME("InstanceOptions")), BUTTON_SUBSCENE, false, TTR("Open in Editor"));
	}
	tooltip += String("\n" + TTR("Inherits:") + " " + p_node->get_scene_inherited_state()->get_path());
	} else if (p_node != get_scene_node() && !p_node->get_scene_file_path().is_empty() && can_open_instance) {
	if (p_item->get_button_by_id(0, BUTTON_SUBSCENE) == -1) {
	p_item->add_button(0, get_editor_theme_icon(SNAME("InstanceOptions")), BUTTON_SUBSCENE, false, TTR("Open in Editor"));
	}
	tooltip += String("\n" + TTR("Instance:") + " " + p_node->get_scene_file_path());
	}

Where the crash is triggered, due to accessing internal data of a freed node

Ability to trigger this might vary based on hardware and general performance as this is a timing issue

[akien-mga]

Makes sense.

[Repiteo]

Thanks!

[AThousandShips]

Thank you!