| """Unit tests for the positional only argument syntax specified in PEP 570.""" |
| |
| import pickle |
| import unittest |
| |
| from test.support import check_syntax_error |
| |
| |
| def global_pos_only_f(a, b, /): |
| return a, b |
| |
| def global_pos_only_and_normal(a, /, b): |
| return a, b |
| |
| def global_pos_only_defaults(a=1, /, b=2): |
| return a, b |
| |
| |
| class PositionalOnlyTestCase(unittest.TestCase): |
| |
| def assertRaisesSyntaxError(self, codestr, regex="invalid syntax"): |
| with self.assertRaisesRegex(SyntaxError, regex): |
| compile(codestr + "\n", "<test>", "single") |
| |
| def test_invalid_syntax_errors(self): |
| check_syntax_error(self, "def f(a, b = 5, /, c): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "def f(a = 5, b, /, c): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "def f(a = 5, b=1, /, c, *, d=2): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "def f(a = 5, b, /): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "def f(*args, /): pass") |
| check_syntax_error(self, "def f(*args, a, /): pass") |
| check_syntax_error(self, "def f(**kwargs, /): pass") |
| check_syntax_error(self, "def f(/, a = 1): pass") |
| check_syntax_error(self, "def f(/, a): pass") |
| check_syntax_error(self, "def f(/): pass") |
| check_syntax_error(self, "def f(*, a, /): pass") |
| check_syntax_error(self, "def f(*, /, a): pass") |
| check_syntax_error(self, "def f(a, /, a): pass", "duplicate argument 'a' in function definition") |
| check_syntax_error(self, "def f(a, /, *, a): pass", "duplicate argument 'a' in function definition") |
| check_syntax_error(self, "def f(a, b/2, c): pass") |
| check_syntax_error(self, "def f(a, /, c, /): pass") |
| check_syntax_error(self, "def f(a, /, c, /, d): pass") |
| check_syntax_error(self, "def f(a, /, c, /, d, *, e): pass") |
| check_syntax_error(self, "def f(a, *, c, /, d, e): pass") |
| |
| def test_invalid_syntax_errors_async(self): |
| check_syntax_error(self, "async def f(a, b = 5, /, c): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "async def f(a = 5, b, /, c): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "async def f(a = 5, b=1, /, c, d=2): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "async def f(a = 5, b, /): pass", "non-default argument follows default argument") |
| check_syntax_error(self, "async def f(*args, /): pass") |
| check_syntax_error(self, "async def f(*args, a, /): pass") |
| check_syntax_error(self, "async def f(**kwargs, /): pass") |
| check_syntax_error(self, "async def f(/, a = 1): pass") |
| check_syntax_error(self, "async def f(/, a): pass") |
| check_syntax_error(self, "async def f(/): pass") |
| check_syntax_error(self, "async def f(*, a, /): pass") |
| check_syntax_error(self, "async def f(*, /, a): pass") |
| check_syntax_error(self, "async def f(a, /, a): pass", "duplicate argument 'a' in function definition") |
| check_syntax_error(self, "async def f(a, /, *, a): pass", "duplicate argument 'a' in function definition") |
| check_syntax_error(self, "async def f(a, b/2, c): pass") |
| check_syntax_error(self, "async def f(a, /, c, /): pass") |
| check_syntax_error(self, "async def f(a, /, c, /, d): pass") |
| check_syntax_error(self, "async def f(a, /, c, /, d, *, e): pass") |
| check_syntax_error(self, "async def f(a, *, c, /, d, e): pass") |
| |
| def test_optional_positional_only_args(self): |
| def f(a, b=10, /, c=100): |
| return a + b + c |
| |
| self.assertEqual(f(1, 2, 3), 6) |
| self.assertEqual(f(1, 2, c=3), 6) |
| with self.assertRaisesRegex(TypeError, r"f\(\) got some positional-only arguments passed as keyword arguments: 'b'"): |
| f(1, b=2, c=3) |
| |
| self.assertEqual(f(1, 2), 103) |
| with self.assertRaisesRegex(TypeError, r"f\(\) got some positional-only arguments passed as keyword arguments: 'b'"): |
| f(1, b=2) |
| self.assertEqual(f(1, c=2), 13) |
| |
| def f(a=1, b=10, /, c=100): |
| return a + b + c |
| |
| self.assertEqual(f(1, 2, 3), 6) |
| self.assertEqual(f(1, 2, c=3), 6) |
| with self.assertRaisesRegex(TypeError, r"f\(\) got some positional-only arguments passed as keyword arguments: 'b'"): |
| f(1, b=2, c=3) |
| |
| self.assertEqual(f(1, 2), 103) |
| with self.assertRaisesRegex(TypeError, r"f\(\) got some positional-only arguments passed as keyword arguments: 'b'"): |
| f(1, b=2) |
| self.assertEqual(f(1, c=2), 13) |
| |
| def test_syntax_for_many_positional_only(self): |
| # more than 255 positional only arguments, should compile ok |
| fundef = "def f(%s, /):\n pass\n" % ', '.join('i%d' % i for i in range(300)) |
| compile(fundef, "<test>", "single") |
| |
| def test_pos_only_definition(self): |
| def f(a, b, c, /, d, e=1, *, f, g=2): |
| pass |
| |
| self.assertEqual(5, f.__code__.co_argcount) # 3 posonly + 2 "standard args" |
| self.assertEqual(3, f.__code__.co_posonlyargcount) |
| self.assertEqual((1,), f.__defaults__) |
| |
| def f(a, b, c=1, /, d=2, e=3, *, f, g=4): |
| pass |
| |
| self.assertEqual(5, f.__code__.co_argcount) # 3 posonly + 2 "standard args" |
| self.assertEqual(3, f.__code__.co_posonlyargcount) |
| self.assertEqual((1, 2, 3), f.__defaults__) |
| |
| def test_pos_only_call_via_unpacking(self): |
| def f(a, b, /): |
| return a + b |
| |
| self.assertEqual(f(*[1, 2]), 3) |
| |
| def test_use_positional_as_keyword(self): |
| def f(a, /): |
| pass |
| expected = r"f\(\) got some positional-only arguments passed as keyword arguments: 'a'" |
| with self.assertRaisesRegex(TypeError, expected): |
| f(a=1) |
| |
| def f(a, /, b): |
| pass |
| expected = r"f\(\) got some positional-only arguments passed as keyword arguments: 'a'" |
| with self.assertRaisesRegex(TypeError, expected): |
| f(a=1, b=2) |
| |
| def f(a, b, /): |
| pass |
| expected = r"f\(\) got some positional-only arguments passed as keyword arguments: 'a, b'" |
| with self.assertRaisesRegex(TypeError, expected): |
| f(a=1, b=2) |
| |
| def test_positional_only_and_arg_invalid_calls(self): |
| def f(a, b, /, c): |
| pass |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 1 required positional argument: 'c'"): |
| f(1, 2) |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 2 required positional arguments: 'b' and 'c'"): |
| f(1) |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 3 required positional arguments: 'a', 'b', and 'c'"): |
| f() |
| with self.assertRaisesRegex(TypeError, r"f\(\) takes 3 positional arguments but 4 were given"): |
| f(1, 2, 3, 4) |
| |
| def test_positional_only_and_optional_arg_invalid_calls(self): |
| def f(a, b, /, c=3): |
| pass |
| f(1, 2) # does not raise |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 1 required positional argument: 'b'"): |
| f(1) |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 2 required positional arguments: 'a' and 'b'"): |
| f() |
| with self.assertRaisesRegex(TypeError, r"f\(\) takes from 2 to 3 positional arguments but 4 were given"): |
| f(1, 2, 3, 4) |
| |
| def test_positional_only_and_kwonlyargs_invalid_calls(self): |
| def f(a, b, /, c, *, d, e): |
| pass |
| f(1, 2, 3, d=1, e=2) # does not raise |
| with self.assertRaisesRegex(TypeError, r"missing 1 required keyword-only argument: 'd'"): |
| f(1, 2, 3, e=2) |
| with self.assertRaisesRegex(TypeError, r"missing 2 required keyword-only arguments: 'd' and 'e'"): |
| f(1, 2, 3) |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 1 required positional argument: 'c'"): |
| f(1, 2) |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 2 required positional arguments: 'b' and 'c'"): |
| f(1) |
| with self.assertRaisesRegex(TypeError, r" missing 3 required positional arguments: 'a', 'b', and 'c'"): |
| f() |
| with self.assertRaisesRegex(TypeError, r"f\(\) takes 3 positional arguments but 6 positional arguments " |
| r"\(and 2 keyword-only arguments\) were given"): |
| f(1, 2, 3, 4, 5, 6, d=7, e=8) |
| with self.assertRaisesRegex(TypeError, r"f\(\) got an unexpected keyword argument 'f'"): |
| f(1, 2, 3, d=1, e=4, f=56) |
| |
| def test_positional_only_invalid_calls(self): |
| def f(a, b, /): |
| pass |
| f(1, 2) # does not raise |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 1 required positional argument: 'b'"): |
| f(1) |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 2 required positional arguments: 'a' and 'b'"): |
| f() |
| with self.assertRaisesRegex(TypeError, r"f\(\) takes 2 positional arguments but 3 were given"): |
| f(1, 2, 3) |
| |
| def test_positional_only_with_optional_invalid_calls(self): |
| def f(a, b=2, /): |
| pass |
| f(1) # does not raise |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 1 required positional argument: 'a'"): |
| f() |
| |
| with self.assertRaisesRegex(TypeError, r"f\(\) takes from 1 to 2 positional arguments but 3 were given"): |
| f(1, 2, 3) |
| |
| def test_no_standard_args_usage(self): |
| def f(a, b, /, *, c): |
| pass |
| |
| f(1, 2, c=3) |
| with self.assertRaises(TypeError): |
| f(1, b=2, c=3) |
| |
| def test_change_default_pos_only(self): |
| def f(a, b=2, /, c=3): |
| return a + b + c |
| |
| self.assertEqual((2,3), f.__defaults__) |
| f.__defaults__ = (1, 2, 3) |
| self.assertEqual(f(1, 2, 3), 6) |
| |
| def test_lambdas(self): |
| x = lambda a, /, b: a + b |
| self.assertEqual(x(1,2), 3) |
| self.assertEqual(x(1,b=2), 3) |
| |
| x = lambda a, /, b=2: a + b |
| self.assertEqual(x(1), 3) |
| |
| x = lambda a, b, /: a + b |
| self.assertEqual(x(1, 2), 3) |
| |
| x = lambda a, b, /, : a + b |
| self.assertEqual(x(1, 2), 3) |
| |
| def test_invalid_syntax_lambda(self): |
| check_syntax_error(self, "lambda a, b = 5, /, c: None", "non-default argument follows default argument") |
| check_syntax_error(self, "lambda a = 5, b, /, c: None", "non-default argument follows default argument") |
| check_syntax_error(self, "lambda a = 5, b, /: None", "non-default argument follows default argument") |
| check_syntax_error(self, "lambda *args, /: None") |
| check_syntax_error(self, "lambda *args, a, /: None") |
| check_syntax_error(self, "lambda **kwargs, /: None") |
| check_syntax_error(self, "lambda /, a = 1: None") |
| check_syntax_error(self, "lambda /, a: None") |
| check_syntax_error(self, "lambda /: None") |
| check_syntax_error(self, "lambda *, a, /: None") |
| check_syntax_error(self, "lambda *, /, a: None") |
| check_syntax_error(self, "lambda a, /, a: None", "duplicate argument 'a' in function definition") |
| check_syntax_error(self, "lambda a, /, *, a: None", "duplicate argument 'a' in function definition") |
| check_syntax_error(self, "lambda a, /, b, /: None") |
| check_syntax_error(self, "lambda a, /, b, /, c: None") |
| check_syntax_error(self, "lambda a, /, b, /, c, *, d: None") |
| check_syntax_error(self, "lambda a, *, b, /, c: None") |
| |
| def test_posonly_methods(self): |
| class Example: |
| def f(self, a, b, /): |
| return a, b |
| |
| self.assertEqual(Example().f(1, 2), (1, 2)) |
| self.assertEqual(Example.f(Example(), 1, 2), (1, 2)) |
| self.assertRaises(TypeError, Example.f, 1, 2) |
| expected = r"f\(\) got some positional-only arguments passed as keyword arguments: 'b'" |
| with self.assertRaisesRegex(TypeError, expected): |
| Example().f(1, b=2) |
| |
| def test_mangling(self): |
| class X: |
| def f(self, *, __a=42): |
| return __a |
| self.assertEqual(X().f(), 42) |
| |
| def test_module_function(self): |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 2 required positional arguments: 'a' and 'b'"): |
| global_pos_only_f() |
| |
| |
| def test_closures(self): |
| def f(x,y): |
| def g(x2,/,y2): |
| return x + y + x2 + y2 |
| return g |
| |
| self.assertEqual(f(1,2)(3,4), 10) |
| with self.assertRaisesRegex(TypeError, r"g\(\) missing 1 required positional argument: 'y2'"): |
| f(1,2)(3) |
| with self.assertRaisesRegex(TypeError, r"g\(\) takes 2 positional arguments but 3 were given"): |
| f(1,2)(3,4,5) |
| |
| def f(x,/,y): |
| def g(x2,y2): |
| return x + y + x2 + y2 |
| return g |
| |
| self.assertEqual(f(1,2)(3,4), 10) |
| |
| def f(x,/,y): |
| def g(x2,/,y2): |
| return x + y + x2 + y2 |
| return g |
| |
| self.assertEqual(f(1,2)(3,4), 10) |
| with self.assertRaisesRegex(TypeError, r"g\(\) missing 1 required positional argument: 'y2'"): |
| f(1,2)(3) |
| with self.assertRaisesRegex(TypeError, r"g\(\) takes 2 positional arguments but 3 were given"): |
| f(1,2)(3,4,5) |
| |
| def test_same_keyword_as_positional_with_kwargs(self): |
| def f(something,/,**kwargs): |
| return (something, kwargs) |
| |
| self.assertEqual(f(42, something=42), (42, {'something': 42})) |
| |
| with self.assertRaisesRegex(TypeError, r"f\(\) missing 1 required positional argument: 'something'"): |
| f(something=42) |
| |
| self.assertEqual(f(42), (42, {})) |
| |
| def test_mangling(self): |
| class X: |
| def f(self, __a=42, /): |
| return __a |
| |
| def f2(self, __a=42, /, __b=43): |
| return (__a, __b) |
| |
| def f3(self, __a=42, /, __b=43, *, __c=44): |
| return (__a, __b, __c) |
| |
| self.assertEqual(X().f(), 42) |
| self.assertEqual(X().f2(), (42, 43)) |
| self.assertEqual(X().f3(), (42, 43, 44)) |
| |
| def test_too_many_arguments(self): |
| # more than 255 positional-only arguments, should compile ok |
| fundef = "def f(%s, /):\n pass\n" % ', '.join('i%d' % i for i in range(300)) |
| compile(fundef, "<test>", "single") |
| |
| def test_serialization(self): |
| pickled_posonly = pickle.dumps(global_pos_only_f) |
| pickled_optional = pickle.dumps(global_pos_only_and_normal) |
| pickled_defaults = pickle.dumps(global_pos_only_defaults) |
| |
| unpickled_posonly = pickle.loads(pickled_posonly) |
| unpickled_optional = pickle.loads(pickled_optional) |
| unpickled_defaults = pickle.loads(pickled_defaults) |
| |
| self.assertEqual(unpickled_posonly(1,2), (1,2)) |
| expected = r"global_pos_only_f\(\) got some positional-only arguments "\ |
| r"passed as keyword arguments: 'a, b'" |
| with self.assertRaisesRegex(TypeError, expected): |
| unpickled_posonly(a=1,b=2) |
| |
| self.assertEqual(unpickled_optional(1,2), (1,2)) |
| expected = r"global_pos_only_and_normal\(\) got some positional-only arguments "\ |
| r"passed as keyword arguments: 'a'" |
| with self.assertRaisesRegex(TypeError, expected): |
| unpickled_optional(a=1,b=2) |
| |
| self.assertEqual(unpickled_defaults(), (1,2)) |
| expected = r"global_pos_only_defaults\(\) got some positional-only arguments "\ |
| r"passed as keyword arguments: 'a'" |
| with self.assertRaisesRegex(TypeError, expected): |
| unpickled_defaults(a=1,b=2) |
| |
| def test_async(self): |
| |
| async def f(a=1, /, b=2): |
| return a, b |
| |
| with self.assertRaisesRegex(TypeError, r"f\(\) got some positional-only arguments passed as keyword arguments: 'a'"): |
| f(a=1, b=2) |
| |
| def _check_call(*args, **kwargs): |
| try: |
| coro = f(*args, **kwargs) |
| coro.send(None) |
| except StopIteration as e: |
| result = e.value |
| self.assertEqual(result, (1, 2)) |
| |
| _check_call(1, 2) |
| _check_call(1, b=2) |
| _check_call(1) |
| _check_call() |
| |
| def test_generator(self): |
| |
| def f(a=1, /, b=2): |
| yield a, b |
| |
| with self.assertRaisesRegex(TypeError, r"f\(\) got some positional-only arguments passed as keyword arguments: 'a'"): |
| f(a=1, b=2) |
| |
| gen = f(1, 2) |
| self.assertEqual(next(gen), (1, 2)) |
| gen = f(1, b=2) |
| self.assertEqual(next(gen), (1, 2)) |
| gen = f(1) |
| self.assertEqual(next(gen), (1, 2)) |
| gen = f() |
| self.assertEqual(next(gen), (1, 2)) |
| |
| def test_super(self): |
| |
| sentinel = object() |
| |
| class A: |
| def method(self): |
| return sentinel |
| |
| class C(A): |
| def method(self, /): |
| return super().method() |
| |
| self.assertEqual(C().method(), sentinel) |
| |
| |
| if __name__ == "__main__": |
| unittest.main() |