def test_exceptions():
# Random product doesn't work with empty iterables
with pytest.raises(IndexError):
iteration_utilities.random_product([])
# There is no element 10 in the tee object so this will raise the
# Exception.
t1, t2 = tee([1, 2, 3, 4, 5])
with pytest.raises(IndexError):
iteration_utilities.tee_lookahead(t1, 10)
# Missing idx or start/stop in replace/remove/getitem
with pytest.raises(TypeError):
iteration_utilities.replace([1, 2, 3], 5)
with pytest.raises(TypeError):
iteration_utilities.remove([1, 2, 3])
with pytest.raises(TypeError):
iteration_utilities.getitem([1, 2, 3])
# Stop smaller than start in replace/remove
with pytest.raises(ValueError):
iteration_utilities.replace(range(10), 5, start=7, stop=5)
with pytest.raises(ValueError):
iteration_utilities.remove(range(10), start=7, stop=5)
# idx smaller than -1 in getitem
with pytest.raises(ValueError):
iteration_utilities.getitem(range(10), (4, 2, -3, 9))
with pytest.raises(ValueError):
iteration_utilities.nth_combination([1], r=-1, index=0)
with pytest.raises(ValueError):
iteration_utilities.nth_combination([1], r=2, index=0)
with pytest.raises(IndexError):
iteration_utilities.nth_combination([1, 2, 3, 4], r=2, index=-20)
with pytest.raises(IndexError):
iteration_utilities.nth_combination([1, 2, 3, 4], r=2, index=20)
def test_exceptions():
# old-style classes don't have the subclasses special member.
if iteration_utilities.EQ_PY2:
class A:
pass
with pytest.raises(TypeError):
list(iteration_utilities.itersubclasses(A))
# Random product doesn't work with empty iterables
with pytest.raises(IndexError):
iteration_utilities.random_product([])
# There is no element 10 in the tee object so this will raise the
# Exception.
t1, t2 = tee([1, 2, 3, 4, 5])
with pytest.raises(IndexError):
iteration_utilities.tee_lookahead(t1, 10)
# Missing idx or start/stop in replace/remove/getitem
with pytest.raises(TypeError):
iteration_utilities.replace([1, 2, 3], 5)
with pytest.raises(TypeError):
iteration_utilities.remove([1, 2, 3])
with pytest.raises(TypeError):
iteration_utilities.getitem([1, 2, 3])
# Stop smaller than start in replace/remove
with pytest.raises(ValueError):
iteration_utilities.replace(range(10), 5, start=7, stop=5)
with pytest.raises(ValueError):
iteration_utilities.remove(range(10), start=7, stop=5)
# idx smaller than -1 in getitem
with pytest.raises(ValueError):
iteration_utilities.getitem(range(10), (4, 2, -3, 9))
def test_empty_input():
empty = []
assert list(iteration_utilities.combinations_from_relations({}, 1)) == []
assert list(
iteration_utilities.combinations_from_relations({'a': [1, 2, 3]},
2)) == []
assert iteration_utilities.consume(empty, 2) is None
assert list(iteration_utilities.flatten(empty)) == []
assert list(iteration_utilities.getitem(range(10), empty)) == []
x, y = iteration_utilities.ipartition(empty, lambda x: x)
assert list(x) == [] and list(y) == []
# no need to test iter_subclasses here
assert list(iteration_utilities.ncycles(empty, 10)) == []
assert list(iteration_utilities.powerset(empty)) == [()]
assert iteration_utilities.random_combination(empty, 0) == ()
assert iteration_utilities.random_combination(empty, 0, True) == ()
assert iteration_utilities.random_permutation(empty, 0) == ()
assert list(iteration_utilities.remove(range(10),
empty)) == list(range(10))
assert list(iteration_utilities.replace(range(10), 20,
empty)) == list(range(10))
# no need to test repeatfunc here
# no need to test tabulate here
assert list(iteration_utilities.tail(empty, 2)) == []
def test_applyfunc_failure1():
with pytest.raises(TypeError):
list(getitem(applyfunc(lambda x: x**T(2), T('a')), stop=3))
def test_applyfunc_normal2():
assert list(getitem(applyfunc(lambda x: x, T(2)),
stop=3)) == [T(2), T(2), T(2)]
def test_applyfunc_normal1():
assert list(getitem(applyfunc(lambda x: x**T(2), T(2)),
stop=3)) == [T(4), T(16), T(256)]
def test_tabulate_normal2():
assert list(getitem(tabulate(T), stop=5)) == [T(0), T(1), T(2), T(3), T(4)]
def test_tabulate_normal1():
assert list(getitem(tabulate(lambda x: x, T2(0)),
stop=5)) == [T2(0), T2(1),
T2(2), T2(3),
T2(4)]