def test_empty_keep(self):
inp = [2, 4, 6, 8, 10]
out = []
self.assertEqual(out, keep(inp, lambda x: x % 2 == 1))
def test_keep_plus_discard(self):
inp = ['1,2,3', 'one', 'almost!', 'love']
out = ['one', 'love', '1,2,3', 'almost!']
self.assertEqual(out, keep(inp, str.isalpha) + discard(inp, str.isalpha))
def test_empty_sequence(self):
self.assertEqual([], keep([], lambda x: x % 2 == 0))
def test_keep_z(self):
inp = ['zebra', 'arizona', 'apple', 'google', 'mozilla']
out = ['zebra', 'arizona', 'mozilla']
self.assertEqual(out, keep(inp, lambda x: 'z' in x))
def test_keep_discard(self):
inp = ['1,2,3', 'one', 'almost!', 'love']
self.assertEqual([], discard(keep(inp, str.isalpha), str.isalpha))
def test_empty_keep(self):
inp = [2, 4, 6, 8, 10]
out = []
self.assertEqual(out, keep(inp, lambda x: x % 2 == 1))
def test_keep_everything(self):
inp = [2, 4, 6, 8, 10]
self.assertEqual(inp, keep(inp, lambda x: x % 2 == 0))
def test_empty_sequence(self):
self.assertEqual([], keep([], lambda x: x % 2 == 0))
def test_keep_plus_discard(self):
inp = ['1,2,3', 'one', 'almost!', 'love']
out = ['one', 'love', '1,2,3', 'almost!']
self.assertEqual(out,
keep(inp, str.isalpha) + discard(inp, str.isalpha))
def test_keep_discard(self):
inp = ['1,2,3', 'one', 'almost!', 'love']
self.assertEqual([], discard(keep(inp, str.isalpha), str.isalpha))
def test_keep_z(self):
inp = ['zebra', 'arizona', 'apple', 'google', 'mozilla']
out = ['zebra', 'arizona', 'mozilla']
self.assertEqual(out, keep(inp, lambda x: 'z' in x))
def test_keep_everything(self):
inp = [2, 4, 6, 8, 10]
self.assertEqual(inp, keep(inp, lambda x: x % 2 == 0))
