The Player abstract superclass. Since this class doesn't have a body for the placeBets, it can't be unit tested directly.

A revised Passenger57 class. This version will be a proper subclass of Player, but still place bets on black until the stake is exhausted. The existing unit test for Passenger57 should continue to work correctly after these changes.

The Martingale subclass of Player.

A unit test class for Martingale. This test should synthesize a fixed list of Outcomes, Bins, and calls a Martingale instance with various sequences of reds and blacks to assure that the bet doubles appropriately on each loss, and is reset on each win.

A revised Game class. This will check the player's playing method before calling placeBets, and do nothing if the player withdraws. It will also call the player's win and lose methods for winning and losing bets.

A unit test class for the revised Game class. Using a non-random generator for Wheel, this should be able to confirm correct operation of the Game for a number of bets.