Task.WhenAll and Task.WhenAny Godot 4.0 GDScript 2.0 implementation

task.gd

class_name Task


# Call all tasks and wait for them to complete, even async ones
static func WhenAll(tasks: Array[Callable]) -> void:
	var awaiter := _Awaiter.new()
	await awaiter.wait(tasks, tasks.size())


# Call all tasks and wait for at least one to complete, even async ones
static func WhenAny(tasks: Array[Callable]) -> void:
	var awaiter := _Awaiter.new()
	await awaiter.wait(tasks, 1)


class _Awaiter:
	signal completed

	var _pending := 0

	func wait(tasks: Array[Callable], pending: int) -> void:
		_pending = pending
		for task in tasks:
			_call(task)

		if _pending > 0:
			await completed

	func _call(task: Callable) -> void:
		await task.call()
		_pending -= 1
		if _pending <= 0:
			completed.emit()