In SceneKit SCNAction hangs when called from completion handler of RunAction

Question

Calling an SCNAction from the completion handler of RunAction seems to hang SceneKit.

A touch event or rotating the device seems to unblock the hang.

To reproduc

Answer 1

Using SCNTransaction with a completionBlock does not suffer from the same problem, so this works fine:

        SCNTransaction.Begin();
        SCNTransaction.AnimationDuration = 3.0f;
        SCNTransaction.SetCompletionBlock(() =>
        {
            Console.WriteLine("DONE ROTATE");
            SCNTransaction.Begin();
            SCNTransaction.AnimationDuration = 3.0f;
            SCNTransaction.SetCompletionBlock(() =>
            {
                Console.WriteLine("DONE MOVEBY");
            });
            ship.Position = new SCNVector3(1.0f, 0.0f, 0.0f);
            SCNTransaction.Commit();
        });
        ship.EulerAngles = new SCNVector3(0.0f, (float)Math.PI / 2, 0.0f);
        SCNTransaction.Commit();

(Also using CABasicAnimation with CAAnimationDelegate to do the callback works OK.)

Since SCNTransaction and CABasicAnimation work, but RunAction doesn't, it really looks like an Apple bug in RunAction.