def test_call_bad(self):
"""Grouper call should raise ValueError if NumItems is not an int"""
g_none = Grouper(None)
g_neg = Grouper(-1)
g_zero = Grouper(0)
g_alpha = Grouper('abc')
for g in (g_none, g_neg, g_zero, g_alpha):
iterator = g('abcd')
self.assertRaises(ValueError, list, iterator)
def test_call(self):
"""Grouper should return lists containing correct number of groups"""
empty = []
s3 = 'abc'
s10 = list(range(10))
g1 = Grouper(1)
g2 = Grouper(2)
g5 = Grouper(5)
self.assertEqual(list(g1(empty)), [])
self.assertEqual(list(g2(empty)), [])
self.assertEqual(list(g5(empty)), [])
self.assertEqual(list(g1(s3)), [['a'], ['b'], ['c']])
self.assertEqual(list(g2(s3)), [['a', 'b'], ['c']])
self.assertEqual(list(g5(s3)), [['a', 'b', 'c']])
self.assertEqual(list(g1(s10)), [[i] for i in range(10)])
self.assertEqual(list(g2(s10)),
[[0, 1], [2, 3], [4, 5], [6, 7], [8, 9]])
self.assertEqual(list(g5(s10)), [[0, 1, 2, 3, 4], [5, 6, 7, 8, 9]])