def test_zero_items_returns_initial_empty_collection(self):
collection = CollectingSink()
transduce(Transducer,
sending(),
empty_iter(),
init=collection())
self.assertEqual(len(collection), 0)
def test_two_items_causes_completion(self):
singular_sink = SingularSink()
transduce(Transducer,
sending(),
[23, 78],
init=singular_sink())
self.assertTrue(singular_sink.has_value)
def test_two_items_returns_two_element_list(self):
collection = CollectingSink()
transduce(Transducer,
sending(),
[23, 78],
init=collection())
self.assertEqual(list(collection), [23, 78])
def test_mutable_inits(self):
"""Tests that the same mutable init object isn't shared across invocations."""
result = transduce(transducer=mapping(lambda x: x),
reducer=appending(),
iterable=range(3))
self.assertListEqual(result, [0, 1, 2])
result = transduce(transducer=mapping(lambda x: x),
reducer=appending(),
iterable=range(3))
self.assertListEqual(result, [0, 1, 2])
def test_ordering_reverse_with_key(self):
result = transduce(transducer=ordering(key=lambda x: len(x),
reverse=True),
reducer=appending(),
iterable="The quick brown fox jumped".split())
self.assertSequenceEqual(result,
['jumped', 'quick', 'brown', 'The', 'fox'])
def test_ordering_preserves_mutable_sequence_type(self):
result = transduce(transducer=ordering(),
reducer=appending(),
iterable=[4, 2, 6, 10, 8],
init=deque())
self.assertIsInstance(result, deque)
self.assertSequenceEqual(result, deque([2, 4, 6, 8, 10]))
def test_windowing_no_padding(self):
result = transduce(transducer=windowing(3, window_type=list),
reducer=appending(),
iterable=[42, 12, 45, 9, 18, 3, 34, 13])
self.assertListEqual(
result, [[42], [42, 12], [42, 12, 45], [12, 45, 9], [45, 9, 18],
[9, 18, 3], [18, 3, 34], [3, 34, 13], [34, 13], [13]])
def test_ordering_preserves_mutable_sequence_type(self):
result = transduce(transducer=ordering(),
reducer=appending(),
iterable=[4, 2, 6, 10, 8],
init=deque())
self.assertIsInstance(result, deque)
self.assertSequenceEqual(result, deque([2, 4, 6, 8, 10]))
def parse_group(lines):
cmd, path_type, r, g, b = lines[0].split(';')
color = float(r), float(g), float(b)
strokes = transduce(
compose(partitioning(lambda s: s.upper().startswith('MOVETO;')),
filtering(lambda lines: len(lines) > 1),
mapping(parse_path)), appending(), lines[1:])
path = PltmePathGroup(strokes, path_type, color)
return path
def test_chained_transducers(self):
result = transduce(transducer=compose(mapping(lambda x: x * x),
filtering(lambda x: x % 5 != 0),
taking(6),
dropping_while(lambda x: x < 15),
distinct()),
reducer=appending(),
iterable=range(20))
self.assertSequenceEqual(result, [16, 36, 49])
def test_chained_transducers(self):
result = transduce(transducer=compose(
mapping(lambda x: x*x),
filtering(lambda x: x % 5 != 0),
taking(6),
dropping_while(lambda x: x < 15),
distinct()),
reducer=appending(),
iterable=range(20))
self.assertSequenceEqual(result, [16, 36, 49])
def test_completing_with_summing_zero_items_returns_identity(self):
def add(a, b):
return a + b
summing = completing(add, identity=0)
result = transduce(Transducer,
summing,
[])
self.assertEqual(result, 0)
def test_completing_with_summing_four_items(self):
def add(a, b):
return a + b
summing = completing(add, identity=0)
result = transduce(Transducer,
summing,
[4, 2, 1, 9])
self.assertEqual(result, 16)
def test_completing_with_multiplying_zero_items_returns_identity(self):
def multiply(a, b):
return a * b
multiplying = completing(multiply, identity=1)
result = transduce(Transducer,
multiplying,
[])
self.assertEqual(result, 1)
def test_completing_with_multiplying_four_items(self):
def multiply(a, b):
return a * b
multiplying = completing(multiply, identity=1)
result = transduce(Transducer,
multiplying,
[4, 2, 1, 9])
self.assertEqual(result, 72)
def minmax_y(self):
def r(accu, item):
min_y = min(accu[0], item[0])
max_y = max(accu[1], item[1])
return min_y, max_y
minmax_accu = transduce(transducer=pipe(
mapping(lambda p: p.minmax_y()), reducing(r)),
reducer=expecting_single(),
iterable=self.paths)
return minmax_accu
def test_windowing_padding(self):
result = transduce(transducer=windowing(3, padding=0, window_type=list),
reducer=appending(),
iterable=[42, 12, 45, 9, 18, 3, 34, 13])
self.assertListEqual(result,
[[0, 0, 42],
[0, 42, 12],
[42, 12, 45],
[12, 45, 9],
[45, 9, 18],
[9, 18, 3],
[18, 3, 34],
[3, 34, 13],
[34, 13, 0],
[13, 0, 0]])
def parse_pltme(source: str):
def parse_path(lines):
def coords(s):
cmd, x, y = s.split(';')
return float(x), float(y)
coords = [coords(l) for l in lines]
return PltmePath(coords)
def parse_group(lines):
cmd, path_type, r, g, b = lines[0].split(';')
color = float(r), float(g), float(b)
strokes = transduce(
compose(partitioning(lambda s: s.upper().startswith('MOVETO;')),
filtering(lambda lines: len(lines) > 1),
mapping(parse_path)), appending(), lines[1:])
path = PltmePathGroup(strokes, path_type, color)
return path
return transduce(
compose(mapping(lambda s: s.strip()),
partitioning(lambda s: s.upper().startswith('STARTPATH;')),
mapping(parse_group)), appending(), source.splitlines())
def test_reducing_with_init(self):
result = transduce(transducer=reducing(operator.add, 10),
reducer=expecting_single(),
iterable=range(10))
self.assertEqual(result, 55)
def test_scanning(self):
result = transduce(transducer=scanning(operator.add),
reducer=appending(),
iterable=range(5))
self.assertListEqual(result, [0, 1, 3, 6, 10])
def test_taking_validation(self):
with self.assertRaises(ValueError):
transduce(transducer=taking(-3),
reducer=appending(),
iterable=[2, 4, 5, 8, 10])
def test_exactly_one_item(self):
result = transduce(mapping(lambda x: x*x),
expecting_single(),
[42])
self.assertEqual(result, 1764)
def test_two_items_returns_two_element_list(self):
result = transduce(Transducer,
adding(),
[23, 78])
self.assertEqual(result, {23, 78})
def test_conjoining_preserves_initial_sequence_type(self):
result = transduce(Transducer,
conjoining(),
(23, 78),
init=[])
self.assertEqual(result, [23, 78])
def test_two_items_returns_two_element_tuple(self):
result = transduce(Transducer,
conjoining(),
[23, 78])
self.assertEqual(result, (23, 78))
def test_taking_while(self):
result = transduce(transducer=taking_while(lambda x: x < 6),
reducer=appending(),
iterable=[2, 4, 5, 8, 10])
self.assertListEqual(result, [2, 4, 5])
def test_dropping(self):
result = transduce(transducer=dropping(3),
reducer=appending(),
iterable=[2, 4, 5, 8, 10])
self.assertListEqual(result, [8, 10])
def test_dropping_validation(self):
with self.assertRaises(ValueError):
transduce(transducer=dropping(-3),
reducer=appending(),
iterable=[2, 4, 5, 8, 10])
def test_dropping(self):
result = transduce(transducer=dropping(3),
reducer=appending(),
iterable=[2, 4, 5, 8, 10])
self.assertListEqual(result, [8, 10])
def test_taking_while(self):
result = transduce(transducer=taking_while(lambda x: x < 6),
reducer=appending(),
iterable=[2, 4, 5, 8, 10])
self.assertListEqual(result, [2, 4, 5])
def test_appending_to_immutable_sequence_raises_attribute_error(self):
with self.assertRaises(AttributeError):
transduce(Transducer,
appending(),
(23, 78),
init=tuple())
def test_mapcatting(self):
result = transduce(transducer=mapcatting(list),
reducer=appending(),
iterable=['new', 'found', 'land'])
self.assertListEqual(result, list("newfoundland"))
def test_zero_items_returns_initial_empty_tuple(self):
result = transduce(Transducer,
conjoining(),
empty_iter())
self.assertEqual(result, tuple())
def test_sending_to_non_sink_raises_attribute_error(self):
with self.assertRaises(AttributeError):
transduce(Transducer,
sending(),
(23, 78),
init=set())
def test_conjoining_to_non_sequence_raises_type_error(self):
with self.assertRaises(TypeError):
transduce(Transducer,
conjoining(),
(23, 78),
init=set())
def test_enumerating_with_start(self):
result = transduce(transducer=enumerating(start=3),
reducer=appending(),
iterable=[2, 4, 6, 8, 10])
self.assertListEqual(result, [(3, 2), (4, 4), (5, 6), (6, 8), (7, 10)])
def test_zero_items_returns_initial_empty_set(self):
result = transduce(Transducer,
adding(),
empty_iter())
self.assertEqual(result, set())
def test_enumerating(self):
result = transduce(transducer=enumerating(),
reducer=appending(),
iterable=[2, 4, 6, 8, 10])
self.assertListEqual(result, [(0, 2), (1, 4), (2, 6), (3, 8), (4, 10)])
def test_adding_to_non_set_raises_attribute_error(self):
with self.assertRaises(AttributeError):
transduce(Transducer,
adding(),
(23, 78),
init=tuple())
def test_scanning_with_init(self):
result = transduce(transducer=scanning(operator.add, 3),
reducer=appending(),
iterable=range(5))
self.assertListEqual(result, [3, 4, 6, 9, 13])
def test_too_many_items(self):
with self.assertRaises(RuntimeError):
transduce(mapping(lambda x: x*x),
expecting_single(),
[])
def test_mapcatting(self):
result = transduce(transducer=mapcatting(list),
reducer=appending(),
iterable=['new', 'found', 'land'])
self.assertListEqual(result, list("newfoundland"))
