def test_empty(self):
colors = Queue()
assert colors.empty() == 'The queue is empty'
colors.shift('Red')
assert colors.empty() == 'The queue is not empty'
colors.shift('Blue')
assert colors.empty() == 'The queue is not empty'
def test_tail_node(self):
colors = Queue()
assert colors.tail_node() is None
colors.shift('Red')
assert colors.tail_node() == 'Red'
colors.shift('Blue')
assert colors.tail_node() == 'Blue'
def test_head_node(self):
for i in range(0, 800):
colors = Queue()
assert colors.head_node() is None
colors.shift('Red')
assert colors.head_node() == 'Red'
colors.shift('Blue')
assert colors.head_node() == 'Red'
def test_shift(self):
for i in range(0, 800):
colors = Queue()
colors.shift('Red')
assert colors.count() == 1
colors.shift('Blue')
assert colors.count() == 2
def test_pop(self):
for i in range(0, 800):
colors = Queue()
colors.shift('Red')
colors.dump('before blue')
colors.shift('Blue')
colors.dump('after blue')
colors.shift('Yellow')
assert colors.pop() == 'Red'
assert colors.pop() == 'Blue'
assert colors.pop() == 'Yellow'
def test_shift(self):
colors = Queue()
colors.shift('Red')
assert colors.count() == 1
colors.shift('Blue')
assert colors.count() == 2