def test_iterator(self):
nums = (n**2 for n in [1, 2, 3, 4])
self.assertEqual(tail(nums, -1), []) # Don't loop for negative n
self.assertEqual(tail(nums, 0), []) # Don't loop for n=0
self.assertEqual(tail(nums, 2), [9, 16]) # Consuming the generator
self.assertEqual(list(nums), []) # The nums generator is now empty
self.assertEqual(tail(nums, 1), []) # n=1 with a now empty generator
def test_zero(self):
self.assertEqual(tail([1, 2], 0), [])
def test_negative_n(self):
nums = [1, 2, 3, 4]
self.assertEqual(tail(nums, -1), [])
self.assertEqual(tail((), -9), [])
def test_tuple(self):
self.assertEqual(tail((1, 2, 3), 3), [1, 2, 3])
def test_string(self):
self.assertEqual(tail('hello', 2), ['l', 'o'])
def test_n_larger_than_iterable_length(self):
nums = [1, 2, 3, 4]
self.assertEqual(tail(nums, 5), [1, 2, 3, 4])
self.assertEqual(tail([], 10), [])
def test_two(self):
self.assertEqual(tail([1, 2], 2), [1, 2])
def test_one(self):
self.assertEqual(tail([1, 2], 1), [2])