How to use SKScene's didBegin to detect when Sprite Node hits enclosure?

Question

How to use SKScene's didBegin to detect when Sprite Node hits enclosure?

I have 100% success when using contactTestBitMask to detect contact between 2 sibling Sprite Nodes .. but cannot solve when a Sprite Node contacts its enclosure:

this works!

myBall = SKSpriteNode(imageNamed: ballImg)
myBall.name = "ball"
myBall.physicsBody?.categoryBitMask    = ballCategory
myBall.physicsBody?.collisionBitMask   = noCollision
myBall.physicsBody?.contactTestBitMask = playerCategory   // Ball hit by Player

NOT so much =

myRoom = SKSpriteNode(imageNamed: roomImg)
myRoom.name = "room"
myRoom.physicsBody?.categoryBitMask    = roomCategory
myRoom.physicsBody?.collisionBitMask   = noCollision
myRoom.physicsBody?.contactTestBitMask = ballCategory   // Room wall hit by Ball

Here's my SKScene's didBegin() code:

func didBegin(_ contact: SKPhysicsContact) {
                                            
     let bodyAName = contact.bodyA.node?.name   // e.g., = player
     let bodyBName = contact.bodyB.node?.name   // e.g., = ball

     let playerHitsBall = ((bodyBName == myPlayer.name) && (bodyAName == myBall.name))  ||
                          ((bodyAName == myPlayer.name) && (bodyBName == myBall.name))
        
     let ballHitsWall   = ((bodyBName == myBall.name) && (bodyAName == myRoom.name))    ||
                          ((bodyAName == myBall.name) && (bodyBName == myRoom.name))

     if playerHitsBall {
         print("works!")
         itsGameViewController.moveBall(dx: dBallX, dy: dBallX)
     }

     if ballHitsWall {
         print("does NOT show")
         itsGameViewController.moveBallIfBallHitsWall()
     }

}

Please note I can generate code to test for contacting the frame of the enclosure outside didBegin - but that adds a ton of overhead.

My real goal is to do it within didBegin if possible.

Based on history, I am probably doing something, although basic, is wrong ... but I can't seem to find it.

Thanks in advance.