Added to RollingStockTests.java - please fix code to pass these:

testExcessPassengersNotAllowedToBoard() 
testBoardReturnsZeroIfCarriageNotFull()

Fixed in TrainTests.java (errors):

testDepartingTrain() - removed erroneous "null" in assertNull
testBoardPassengersValidTrainNegative() - Changed "PASSENGERS" (Integer)
to "PASSENGER" (Carriage)
testGetFirstCarriage_MultipleCarriage() - Changed "Freight" to
"GOODS_TYPE"
testNumberOfSeats_MultiplePassengerCar() - Moved all passenger cars to
be added before freight car
testBoardPassengersValidComboTrainPassengerMultiple() - Moved all
passenger cars to be added before freight car
testNumberOfSeats_DualPassengerCars() - Moved all passenger cars to be
added before freight car

Fixed in TrainTests.java (Invalid tests):

testBoardPassengersInvalidTrain() - should not produce exception;
changed to test that "board" returned all 20 passengers
testAddPassengerToLocoFreight() - Changed so that it expects and
exception. Cannot add a passenger car after a freight car

-------------------------------------------------------------------------------------

25/26 tests passed.

testBoardTooManyPassengersValidTrain() DID NOT PASS.

Only 1 didn't pass, despite numberOnBoard() not being implemented
correctly (it's currently trying to get the number of people on board
individual carriages and adding this to the total, however, our program
is not currently adding passengers to individual carriages.

More tests to come to test for these cases.

Naming conventions need some consistency - have emailed Jim about which
conventions to use.