def test_only_lower_bound_implies_same_upper_bound(self):
def func(self_, arg1, arg2, arg3):
pass
decorator = arity(3)
self.assertRaises(UsageError, decorator(func), (self, 1, 2))
decorator(func)(self, 1, 2, 3) # Does not raise
self.assertRaises(UsageError, decorator(func), (self, 1, 2, 3, 4))
def test_different_upper_and_lower_bounds(self):
def func(self_, arg1, arg2, arg3):
pass
decorator = arity(2, 3)
self.assertRaises(UsageError, decorator(func), (self, 1))
decorator(func)(self, 1, 2) # Does not raise
decorator(func)(self, 1, 2, 3) # Does not raise
self.assertRaises(UsageError, decorator(func), (self, 1, 2, 3, 4))
def test_decorator_forwards_arguments(self):
def func(self_, arg1):
self.assertEqual(self_, self)
self.assertEqual(arg1, "foo")
called[0] = True
called = [False]
decorator = arity(1)
decorator(func)(self, "foo")
self.assertTrue(called[0])
def test_missing_arguments_are_set_to_None(self):
def func(self_, arg1, arg2, arg3):
self.assertEqual(arg1, 1)
self.assertTrue(arg2 is None)
self.assertTrue(arg3 is None)
called[0] = True
called = [False]
decorator = arity(1, 3)
decorator(func)(self, 1)
self.assertTrue(called[0])
def test_usage_error_messages(self):
def func(self_):
pass
with self.assertRaisesRegexp(UsageError,
"subcommand expects 0 arguments"):
arity(0)(func)(self, 1)
with self.assertRaisesRegexp(UsageError,
"subcommand expects 1 argument"):
arity(1)(func)(self, 1, 2)
with self.assertRaisesRegexp(UsageError,
"subcommand expects 2 arguments"):
arity(2)(func)(self, 1, 2, 3)
with self.assertRaisesRegexp(
UsageError, "subcommand expects between 1 and 2 arguments"):
arity(1, 2)(func)(self, 1, 2, 3)