def test_mismatching_typevariables_raises(self):
with raises(StrictTypeError, 'Expected argument'):
asum = arrow(self.add, A, A, A)
asum(3, 4.0) # <- both should be of the same type
with raises(StrictTypeError, 'Expected argument'):
afloat = arrow(float, A, A) # <- should return float
afloat(1)
def test_compose_left(self):
sum_of_squares = lambda x, y: x**2 + y**2
f = arrow(sum_of_squares, Int, Int, Int)
g = arrow(math.sqrt, Int, Real)
assert (g << f)(3, 4) == 5.0
def test_wrong_arg_types_raises(self, length):
arglist = [Bool, Int, Real]
misfits = [4, 0.7, 1 + 1j]
with raises(StrictTypeError, 'is of wrong type for signature'):
t = arrow(*[self.argcount] + arglist[:length] + [Int])
t(*misfits[:length])
def test_wrong_return_type_raises(self):
with raises(StrictTypeError, 'is of wrong type for signature'):
t = arrow(self.argcount, A, Bool) # <- bool should be Int
t(1)
def test_wrong_arg_count_raises(self):
with raises(StrictTypeError, 'Wrong number of arguments in'):
t = arrow(self.no, A, Bool)
t('one', 'extra') # <-- Expects only one argument
def test_two_args_fun(self):
asum = arrow(self.add, A, A, Int)
args = (1, 2)
assert asum(*args) == self.add(*args)
assert type(asum(*args)) is int
def test_one_arg_fun(self):
ano = arrow(self.no, A, Bool)
val = True
assert ano(val) is not(val)
assert type(ano(val)) is bool
def test_uncallable_fun_raises(self):
uncallable = 5
with raises(StrictTypeError, 'is not callable'):
arrow(uncallable, A, A)
def test_less_than_two_types_raises(self, types):
with raises(TypeError, 'Needs at least two types:'):
args = [int] + types
arrow(*args)
def test_init(self):
t = arrow(Bool, A, Bool, A=Num)
assert t._fun is Bool
assert t.signature == signature(A, Bool, A=Num)
