GKScene extension for framework-local GameplayKit scene assets

GKScene+Frameworks.swift

/// Adds a convenience initializer for loading scenes from framework targets.
public extension GKScene {

    /// Loads the bundle-specific SpriteKit scene file, creating a GKScene object containing the SpriteKit scene and associated GameplayKit objects.
    /// - Parameters:
    ///     - filename: The name of a scene file in the given bundle.
    ///     - bundle: The bundle containing the scene file.
    ///
    /// - Returns: A new GameplayKit scene.
    ///
    /// Use this initializer to load SpriteKit scenes (.sks files) that are not local to your application's main bundle.
    convenience init?(fileNamed filename: String, in bundle: Bundle) {
        guard
            let main = Bundle.main.resourcePath,
            let full = bundle.url(forResource: filename, withExtension: "sks")?.path
        else {
            return nil
        }

        let relative = full.replacingOccurrences(of: "\(main)/", with: "")
        self.init(fileNamed: relative)
    }
}

Currently this only works on real devices.