def test_vending_machine_errors_on_bad_arguments():
"""
Negative tests for better developer feedback
"""
with pytest.raises(expected_exception=Exception):
vendmach.VendingMachine(itemrequest='AAA')
with pytest.raises(expected_exception=Exception):
vendmach.VendingMachine(itemrequest='AAA', coins=1)
with pytest.raises(expected_exception=vendmach.BadCoinError):
vendmach.VendingMachine(itemrequest='AAA', coins=';lkj')
def test_vendingmachine_knows_if_coins_are_enough():
choice = list(vendmach.config.VALID_ITEMS)[0]
machine = vendmach.VendingMachine(itemrequest=choice, coins=[10])
assert not machine.is_paid
machine.coins = [50, 50, 50, 50]
assert machine.is_paid
def test_can_not_update_coins_with_not_configured_coins():
machine = vendmach.VendingMachine(
itemrequest='nuke license',
coins=[],
)
with pytest.raises(expected_exception=vendmach.BadCoinError):
machine.coins = [123451]
def test_if_item_is_not_paid_for_item_attr_is_none():
choice = list(vendmach.config.VALID_ITEMS)[0]
mchine = vendmach.VendingMachine(itemrequest=choice, coins=[10])
assert not mchine.is_paid
assert mchine.item is None
mchine.coins = [50, 50, 50, 50]
assert mchine.is_paid
assert mchine.item == choice
def test_functionality_example():
# The item's name we want
itemname = 'renderfarm time'
# The budget
budget = []
machine = vendmach.VendingMachine(
itemrequest=itemname,
coins=budget,
)
assert machine.item is None
# budget is not enough
assert not machine.is_paid
budget += [-1]
# The budget contains coins not configured
# for the vending machine
with pytest.raises(expected_exception=vendmach.BadCoinError):
machine.coins = budget
assert machine.item is None
# budget is not enough
assert not machine.is_paid
budget = [10]
machine.coins = budget
# budget is still not enough
assert machine.item is None
assert not machine.is_paid
budget = [10, 10, 50]
machine.coins = budget
# budget is just enough, we get the item. The machine's state
# is paid. There's no change.
assert machine.item == itemname
assert machine.is_paid
assert not machine.change
# adding more to the budget, maybe we get another item (not implemented...)
machine.coins += [20, 50]
# we get the item(s), the machine is paid and we get change back.
# we get back what we added as extra, the item was precisely paid
# for the last time.
assert machine.item == itemname
assert machine.is_paid
assert machine.change == [50, 20]
# we have a bigger budget this time
machine.coins = [50, 50]
# we get the item and get change back
assert machine.item == itemname
assert machine.is_paid
assert machine.change == [20, 10]
# we can get an empty machine and ask it for stuff later
# when we made up our mind.
machine = vendmach.VendingMachine()
# we don't get our item of course
assert not machine.item
assert not machine.is_paid
# if we set the bidget, but don't choose yet we don't get an item
machine.coins = [50, 50, 50, 50, 50]
assert machine.item is None
assert machine.is_paid is None
def test_can_instantiate_machine_without_arguments_for_later_use():
machine = vendmach.VendingMachine()
assert isinstance(machine, vendmach.VendingMachine)
def test_vendingmachine_returns_change_if_overpaid(budget, expected):
machine = vendmach.VendingMachine(itemrequest='nuke license', coins=budget)
assert machine.change == expected
def test_can_init_vendingmachine_w_item_and_coins():
choice = list(vendmach.config.VALID_ITEMS)[0]
vendmach.VendingMachine(itemrequest=choice, coins=[10])