| """Unit tests for the positional only argument syntax specified in PEP 570.""" | |
| import dis | |
| import pickle | |
| import types | |
| 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", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "def f(a = 5, b, /, c): pass", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "def f(a = 5, b=1, /, c, *, d=2): pass", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "def f(a = 5, b, /): pass", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "def f(a, /, b = 5, c): pass", "parameter without a default follows parameter with a default") | |
| 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 parameter 'a' in function definition") | |
| check_syntax_error(self, "def f(a, /, *, a): pass", "duplicate parameter '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", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "async def f(a = 5, b, /, c): pass", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "async def f(a = 5, b=1, /, c, d=2): pass", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "async def f(a = 5, b, /): pass", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "async def f(a, /, b = 5, c): pass", "parameter without a default follows parameter with a default") | |
| 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 parameter 'a' in function definition") | |
| check_syntax_error(self, "async def f(a, /, *, a): pass", "duplicate parameter '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", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "lambda a = 5, b, /, c: None", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "lambda a = 5, b=1, /, c, *, d=2: None", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "lambda a = 5, b, /: None", "parameter without a default follows parameter with a default") | |
| check_syntax_error(self, "lambda a, /, b = 5, c: None", "parameter without a default follows parameter with a default") | |
| 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 parameter 'a' in function definition") | |
| check_syntax_error(self, "lambda a, /, *, a: None", "duplicate parameter '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_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_annotations_in_closures(self): | |
| def inner_has_pos_only(): | |
| def f(x: int, /): ... | |
| return f | |
| assert inner_has_pos_only().__annotations__ == {'x': int} | |
| class Something: | |
| def method(self): | |
| def f(x: int, /): ... | |
| return f | |
| assert Something().method().__annotations__ == {'x': int} | |
| def multiple_levels(): | |
| def inner_has_pos_only(): | |
| def f(x: int, /): ... | |
| return f | |
| return inner_has_pos_only() | |
| assert multiple_levels().__annotations__ == {'x': int} | |
| 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) | |
| def test_annotations_constant_fold(self): | |
| def g(): | |
| def f(x: not (int is int), /): ... | |
| # without constant folding we end up with | |
| # COMPARE_OP(is), IS_OP (0) | |
| # with constant folding we should expect a IS_OP (1) | |
| code_obj = next(const for const in g.__code__.co_consts | |
| if isinstance(const, types.CodeType) and const.co_name == "__annotate__") | |
| codes = [(i.opname, i.argval) for i in dis.get_instructions(code_obj)] | |
| self.assertNotIn(('UNARY_NOT', None), codes) | |
| self.assertIn(('IS_OP', 1), codes) | |
| if __name__ == "__main__": | |
| unittest.main() |