def test_chain(self):
add_one = fun.map(lambda x: x + "1")
upper = fun.map(str.upper)
result = fun.chain(
["a", "b", "c", "d"],
add_one,
upper,
list
)
self.assertEqual(result, ["A1", "B1", "C1", "D1"])
big_transform = [add_one, upper]
result = fun.chain(
["a", "b", "c", "d"],
*big_transform,
list
)
self.assertEqual(result, ["A1", "B1", "C1", "D1"])
result = fun.chain(
["a", "b", "c", "d"],
*big_transform,
fun.filter(lambda x: x < "C1"),
list
)
self.assertEqual(result, ["A1", "B1"])
result = fun.chain(
["a", "b", "c", "d"],
*big_transform,
fun.sort(reverse=True),
list
)
self.assertEqual(result, ["D1", "C1", "B1", "A1"])
side_effects = []
save_value = fun.tap(side_effects.append)
result = fun.chain(
["a", "b", "c", "d"],
save_value,
*big_transform,
save_value,
fun.sort(reverse=True),
list
)
self.assertEqual(result, ["D1", "C1", "B1", "A1"])
self.assertEqual(side_effects, [
["a", "b", "c", "d"],
["A1", "B1", "C1", "D1"]
])
result = fun.chain(
["a", "b", "c", "d"],
*big_transform,
fun.reduce(lambda acc, x: acc + x),
)
self.assertEqual(result, "A1B1C1D1")
def test_sort_with_key(self):
sorter = fun.sort(lambda x: x[1])
result = sorter([(1, "b"), (2, "a"), (3, "c")])
self.assertEqual(list(result), [(2, "a"), (1, "b"), (3, "c")])
def test_sort_in_reverse_with_tuples(self):
sorter = fun.sort(reverse=True)
result = sorter([('key3', 1), ('key1', 2), ('key2', 3)])
self.assertEqual(list(result), [('key3', 1), ('key2', 3), ('key1', 2)])
def test_sort_in_reverse(self):
sorter = fun.sort(reverse=True)
result = sorter([2, 4, 3, 1])
self.assertEqual(list(result), [4, 3, 2, 1])
def test_sort_with_defaults_and_tuples(self):
sorter = fun.sort()
result = sorter([('key3', 1), ('key1', 2), ('key2', 3)])
self.assertEqual(list(result), [('key1', 2), ('key2', 3), ('key3', 1)])
def test_sort_with_defaults(self):
sorter = fun.sort()
result = sorter([2, 4, 3, 1])
self.assertEqual(list(result), [1, 2, 3, 4])