regression-test-project/ReparentingDeleting/ReparentingDeleting.gd

extends Node

var number_of_nodes : int = 0

var collected_nodes : Array = []
var disabled_classes : Array = [
	"NavigationAgent2D", "NavigationAgent3D","GPUParticlesCollisionHeightField",
	"ReflectionProbe", # Cause errors, not sure about it
] # Just add name of any class if cause problems

func collect() -> void:
	var classes : Array = ClassDB.get_class_list()
	classes.sort()
	for name_of_class in classes:
		if ClassDB.is_parent_class(name_of_class,"Node"):
			if name_of_class.find("Editor") != -1: # We don't want to test editor nodes
				continue
			if disabled_classes.has(name_of_class): # Class is disabled
				continue
			if ClassDB.can_instance(name_of_class): # Only instantable nodes can be used
				collected_nodes.append(name_of_class)

func _ready() -> void:
	seed(405)
	collect()
	number_of_nodes = max(collected_nodes.size(),200) # Use at least all nodes, or more if you want(168 is probably number nodes)
	for i in range(number_of_nodes): 
		var index = i
		if i >= collected_nodes.size(): # Wrap values
			index = i % collected_nodes.size()
			
		var child : Node = ClassDB.instance(collected_nodes[index])
		child.set_name("Special Node " + str(i))
		add_child(child)
	
## It is quite easy algorithm to reparent and delete items
# - Add multiple nodes to scene
# - Set name to each
# - In process
#   - Get random node
#   - Remove its parent
#   - Play with a russian roulette
#   - If node will be deleted, be sure to get list of its all children and then 
#     replace all with new nodes(change also name) and old remove with queue_free()  
#   - Get another random node
#   - If nodes are the same, add node to root one(cannot set self as self parent) and repeat steps
#   - If second node is child of first, add first node to root one(prevents from memory leaks due invalid reparenting)
#   - At the end add first random node as child of second

func _process(delta: float) -> void:
	assert(Performance.get_monitor(Performance.OBJECT_ORPHAN_NODE_COUNT) == 0) # Don't work good with running more than 1 this scene
	
	var choosen_node : Node
	var parent_of_node : Node
	for i in range(5):
		var number : String = "Special Node " + str(randi() % number_of_nodes)
		choosen_node = find_node(number,true,false)
		parent_of_node = choosen_node.get_parent()
		
		var random_node = find_node("Special Node " + str(randi() % number_of_nodes),true,false)
		parent_of_node.remove_child(choosen_node)
		
#		if randi() % 6 == 0: # 16% chance to remove node with children
#			var names_to_remove : Array = find_all_special_children_names(choosen_node)
#			for name_to_remove in names_to_remove:
#				var node : Node = ClassDB.instance(collected_nodes[randi() % collected_nodes.size()])
#				node.set_name(name_to_remove)
#				add_child(node)
#			choosen_node.queue_free()
#			continue
		
		
		if choosen_node.find_node(random_node.get_name(),true,false) != null: # Cannot set as node parent one of its child
			add_child(choosen_node)
			continue
		if choosen_node == random_node: # Do not reparent node to self
			add_child(choosen_node)
			continue
		random_node.add_child(choosen_node)

# Finds recusivelly all child nodes which are not internal
func find_all_special_children_names(node : Node) -> Array:
	var array : Array = []
	array.append(node.get_name())
	for child in node.get_children():
		if String(child.get_name()).begins_with("Special Node"):
			array.append_array(find_all_special_children_names(child))
	
	return array