ObjectDisposeBag.swift

import Foundation
import Combine

@available(iOS 13.0, *)
extension NSObject {
    private struct AssociatedKeys {
        static var disposeBag: UInt8 = 0
    }

    /// Stores a Combine AnyCancellable with the current object's disposeBag.
    func addToDisposeBag(_ cancellable: AnyCancellable) {
        synchronized {
            var bag = objc_getAssociatedObject(self, &AssociatedKeys.disposeBag) as? [AnyCancellable] ?? []
            bag.append(cancellable)
            objc_setAssociatedObject(self, &AssociatedKeys.disposeBag, bag, .OBJC_ASSOCIATION_RETAIN_NONATOMIC)
        }
    }
}