diff --git a/Lib/test/test_pep695_aug.py b/Lib/test/test_pep695_aug.py new file mode 100644 index 0000000..672f17a --- /dev/null +++ b/Lib/test/test_pep695_aug.py @@ -0,0 +1,356 @@ +import ast +import keyword +import pathlib +import textwrap +import types +import typing +import unittest + + +CPYTHON_ROOT = pathlib.Path(__file__).resolve().parents[2] + + +def run_source(source, namespace=None): + ns = {} if namespace is None else dict(namespace) + exec(textwrap.dedent(source), ns) + return ns + + +class TypeParameterSyntaxAugmentedTests(unittest.TestCase): + def test_ast_unparse_preserves_all_type_parameter_forms(self): + cases = [ + ("class Box[T]:\n pass", "class Box[T]:"), + ("def ident[T](x: T) -> T:\n return x", "def ident[T]"), + ("async def coro[T]():\n pass", "async def coro[T]"), + ("class Array[*Shape]:\n pass", "class Array[*Shape]:"), + ("def deco[**P]():\n pass", "def deco[**P]"), + ("type Vec[T] = list[T]", "type Vec[T] = list[T]"), + ] + + for source, expected in cases: + with self.subTest(source=source): + rendered = ast.unparse(ast.parse(source)) + self.assertIn(expected, rendered) + self.assertNotIn("alias Vec", rendered) + self.assertNotIn("Box(T)", rendered) + + def test_source_distribution_keeps_type_parameter_grammar_and_soft_keyword(self): + grammar = (CPYTHON_ROOT / "Grammar" / "python.gram").read_text() + keyword_source = (CPYTHON_ROOT / "Lib" / "keyword.py").read_text() + + self.assertIn("type_params[asdl_typeparam_seq*]", grammar) + self.assertIn("'*' a=NAME", grammar) + self.assertIn("'**' a=NAME", grammar) + self.assertIn('"type" n=NAME t=[type_params]', grammar) + self.assertIn("'type'", keyword_source) + self.assertTrue(keyword.issoftkeyword("type")) + + def test_typing_forward_union_and_invalid_variadic_specialization(self): + compile("class NeedsPEP695[T]:\n pass", "", "exec") + + t = typing.TypeVar("T") + union = t | "Later" + self.assertEqual(typing.get_args(union)[0], t) + self.assertIn("Later", repr(union)) + + ts = typing.TypeVarTuple("Ts") + us = typing.TypeVarTuple("Us") + alias = tuple[typing.Unpack[ts], typing.Unpack[us]] + with self.assertRaises(TypeError): + alias[int, str] + + p = typing.ParamSpec("P") + callback = typing.Callable[p, int] + with self.assertRaises(TypeError): + callback[()] + + def test_implicit_type_parameters_expose_variance_and_exact_runtime_tuple(self): + ns = run_source( + """ + class Box[T, *Ts, **P]: + pass + + def func[S, **Q](): + pass + + type Alias[*As] = tuple[*As] + """ + ) + + t, ts, p = ns["Box"].__type_params__ + self.assertEqual([param.__name__ for param in (t, ts, p)], ["T", "Ts", "P"]) + self.assertTrue(t.__infer_variance__) + self.assertTrue(p.__infer_variance__) + self.assertIsInstance(ts, typing.TypeVarTuple) + self.assertEqual(ns["Alias"].__type_params__, (ns["Alias"].__type_params__[0],)) + self.assertIsInstance(ns["Alias"].__type_params__[0], typing.TypeVarTuple) + self.assertEqual(ns["Box"].__parameters__, (t, ts, p)) + self.assertEqual( + types.get_original_bases(ns["Box"]), + (typing.Generic[t, typing.Unpack[ts], p],), + ) + + s, q = ns["func"].__type_params__ + self.assertEqual((s.__name__, q.__name__), ("S", "Q")) + self.assertTrue(s.__infer_variance__) + self.assertTrue(q.__infer_variance__) + + def test_public_type_parameter_constructors_reject_invalid_combinations(self): + with self.assertRaises(ValueError): + typing.TypeVar("T", infer_variance=True, covariant=True) + with self.assertRaises(ValueError): + typing.ParamSpec("P", infer_variance=True, contravariant=True) + with self.assertRaises(TypeError): + typing.TypeVar("SingleConstraint", int) + with self.assertRaises(TypeError): + typing.TypeVar("BoundAndConstraints", int, str, bound=object) + + tv = typing.TypeVar("T") + with self.assertRaises(TypeError): + typing.TypeAliasType("Alias", list[tv], type_params=[tv]) + + def test_lazy_bounds_constraints_and_alias_values_are_cached(self): + ns = run_source( + """ + events = [] + def mark(value): + events.append(value) + return value + + class BoundBox[T: mark(int)]: + pass + + class ConstraintBox[T: (mark(str), bytes)]: + pass + + type Alias = mark(float) + """ + ) + + (bound_t,) = ns["BoundBox"].__type_params__ + self.assertEqual(ns["events"], []) + self.assertIs(bound_t.__bound__, int) + self.assertIs(bound_t.__bound__, int) + self.assertEqual(ns["events"], [int]) + + (constraint_t,) = ns["ConstraintBox"].__type_params__ + self.assertEqual(constraint_t.__constraints__, (str, bytes)) + self.assertEqual(constraint_t.__constraints__, (str, bytes)) + self.assertEqual(ns["events"], [int, str]) + + self.assertIs(ns["Alias"].__value__, float) + self.assertIs(ns["Alias"].__value__, float) + self.assertEqual(ns["events"], [int, str, float]) + + def test_type_alias_public_runtime_contract(self): + ns = run_source( + """ + type NonGeneric = int + type Variadic[*Ts] = tuple[*Ts] + type Plain = int + """ + ) + + non_generic = ns["NonGeneric"] + variadic = ns["Variadic"] + plain = ns["Plain"] + + with self.assertRaises(TypeError): + non_generic[str] + + (ts,) = variadic.__type_params__ + self.assertIsInstance(ts, typing.TypeVarTuple) + self.assertEqual(variadic.__parameters__, (*ts,)) + self.assertIs(plain.__value__, int) + + union = plain | str + self.assertIsInstance(union, types.UnionType) + self.assertEqual(typing.get_args(union), (plain, str)) + + def test_bounds_constraints_and_empty_type_params_are_classified_correctly(self): + ns = run_source( + """ + class Bounds[T: int, S: (str, bytes)]: + pass + + class Pair[T, U]: + pass + + class Plain: + pass + + def plain_func(): + pass + """ + ) + + t, s = ns["Bounds"].__type_params__ + self.assertIs(t.__bound__, int) + self.assertEqual(t.__constraints__, None) + self.assertIs(s.__bound__, None) + self.assertEqual(s.__constraints__, (str, bytes)) + + self.assertEqual([p.__name__ for p in ns["Pair"].__type_params__], ["T", "U"]) + self.assertEqual(ns["Plain"].__type_params__, ()) + self.assertEqual(ns["plain_func"].__type_params__, ()) + + def test_type_parameter_scopes_and_prohibited_expressions(self): + bad_sources = [ + "class C[T, T]:\n pass", + "class C[T]:\n def m():\n nonlocal T", + "type Alias = (x := int)", + "class C[T := int]:\n pass", + "class C[T: (x := int)]:\n pass", + ] + for source in bad_sources: + with self.subTest(source=source): + with self.assertRaises(SyntaxError): + compile(source, "", "exec") + + ns = run_source( + """ + class Outer: + Bound = int + class Inner[T: Bound]: + pass + """ + ) + (inner_t,) = ns["Outer"].Inner.__type_params__ + self.assertIs(inner_t.__bound__, int) + + def test_manual_ast_type_parameter_nodes_compile_and_validate(self): + module = ast.Module( + body=[ + ast.FunctionDef( + name="identity", + args=ast.arguments( + posonlyargs=[], + args=[ast.arg("value")], + kwonlyargs=[], + kw_defaults=[], + defaults=[], + ), + body=[ast.Return(ast.Name("value", ast.Load()))], + decorator_list=[], + returns=None, + typeparams=[ + ast.TypeVar("T", bound=ast.Name("int", ast.Load())), + ], + ), + ast.AsyncFunctionDef( + name="async_identity", + args=ast.arguments( + posonlyargs=[], + args=[ast.arg("value")], + kwonlyargs=[], + kw_defaults=[], + defaults=[], + ), + body=[ast.Return(ast.Name("value", ast.Load()))], + decorator_list=[], + returns=None, + typeparams=[ast.ParamSpec("P")], + ), + ast.ClassDef( + name="Array", + bases=[], + keywords=[], + body=[ast.Pass()], + decorator_list=[], + typeparams=[ast.TypeVarTuple("Shape")], + ), + ast.TypeAlias( + name=ast.Name("Alias", ast.Store()), + typeparams=[ast.TypeVar("A")], + value=ast.Name("list", ast.Load()), + ), + ], + type_ignores=[], + ) + ast.fix_missing_locations(module) + namespace = {} + exec(compile(module, "", "exec"), namespace) + + (func_t,) = namespace["identity"].__type_params__ + self.assertIs(func_t.__bound__, int) + (async_p,) = namespace["async_identity"].__type_params__ + self.assertIsInstance(async_p, typing.ParamSpec) + (shape,) = namespace["Array"].__type_params__ + self.assertIsInstance(shape, typing.TypeVarTuple) + (alias_a,) = namespace["Alias"].__type_params__ + self.assertEqual(alias_a.__name__, "A") + self.assertIs(namespace["Alias"].__value__, list) + + def test_typing_runtime_dunder_and_paramspec_attr_contracts(self): + compile("class NeedsPEP695[T]:\n pass", "", "exec") + + t = typing.TypeVar("T") + p = typing.ParamSpec("P") + ts = typing.TypeVarTuple("Ts") + + self.assertEqual(t.__reduce__(), "T") + self.assertEqual(p.__reduce__(), "P") + self.assertEqual(ts.__reduce__(), "Ts") + self.assertEqual(repr(p.args), "P.args") + self.assertEqual(repr(p.kwargs), "P.kwargs") + self.assertIs(p.args.__origin__, p) + self.assertIs(p.kwargs.__origin__, p) + self.assertEqual(p.args, p.args) + self.assertNotEqual(p.args, p.kwargs) + + with self.assertRaisesRegex(TypeError, "Cannot subclass"): + class BadTypeVar(t): + pass + + with self.assertRaisesRegex(TypeError, "Cannot subclass"): + class BadParamSpec(p): + pass + + with self.assertRaisesRegex(TypeError, "Cannot subclass"): + class BadTypeVarTuple(ts): + pass + + self.assertEqual( + typing.Callable[p, int][[str, bytes]], + typing.Callable[[str, bytes], int], + ) + self.assertEqual(tuple[typing.Unpack[ts]][int, str].__args__, (int, str)) + + def test_regenerated_parser_keeps_broad_public_grammar_paths(self): + compile("class NeedsPEP695[T]:\n pass", "", "exec") + + valid_sources = [ + "value = (lambda a, b=1, *args, c=2, **kw: (a, b, args, c, kw))(0)", + "items = [x * y for x in range(3) for y in range(2) if x != y]", + "mapping = {k: v for k, v in [('a', 1), ('b', 2)] if v}", + "result = (x for x in range(4) if x % 2)", + "def f(a, /, b: int = 1, *args, c, d=2, **kw) -> tuple:\n return a, b, args, c, d, kw", + "async def afunc(x):\n async with manager() as value:\n async for item in value:\n yield item", + "try:\n raise ExceptionGroup('x', [ValueError()])\nexcept* ValueError as exc:\n handled = exc\nelse:\n handled = None\nfinally:\n done = True", + "match {'kind': 'point', 'x': 1, 'y': 2}:\n case {'kind': 'point', 'x': x, 'y': y} if x < y:\n result = (x, y)\n case _:\n result = None", + "text = f'{1 + 2 = !r:>10}'", + "with (nullcontext(1) as first, nullcontext(2) as second):\n pair = first, second", + "type Alias[T] = tuple[T, list[T]]", + "class Derived[T](Base[T], keyword=True):\n attr: T\n def method[U](self, value: U) -> tuple[T, U]:\n return self.attr, value", + ] + for source in valid_sources: + with self.subTest(source=source): + compile(source, "", "exec") + + invalid_sources = [ + "lambda a=1, b: a", + "def bad(a=1, b):\n pass", + "class Bad[T, T]:\n pass", + "type Alias = (x := int)", + "f'{value!}'", + "try:\n pass\nexcept* ValueError:\n pass\nexcept Exception:\n pass", + "match value:\n case [x, *x]:\n pass", + ] + for source in invalid_sources: + with self.subTest(source=source): + with self.assertRaises(SyntaxError): + compile(source, "", "exec") + + +if __name__ == "__main__": + unittest.main() diff --git a/Lib/test/test_pep695_stability_aug.py b/Lib/test/test_pep695_stability_aug.py new file mode 100644 index 0000000..2efe04a --- /dev/null +++ b/Lib/test/test_pep695_stability_aug.py @@ -0,0 +1,44 @@ +import string +import sys +import unittest + + +class TypeParameterSyntaxStabilityAugmentedTests(unittest.TestCase): + def test_regular_class_and_function_execution_are_stable(self): + class Accumulator: + def __init__(self, initial=0): + self.total = initial + + def add(self, *values): + for value in values: + self.total += value + return self.total + + acc = Accumulator(5) + self.assertEqual(acc.add(1, 2, 3), 11) + self.assertEqual([x * x for x in range(5)], [0, 1, 4, 9, 16]) + + def test_string_template_and_formatter_are_stable(self): + template = string.Template("$name scored ${points} points") + self.assertEqual( + template.substitute(name="Ada", points=42), + "Ada scored 42 points", + ) + self.assertEqual("{name}:{value:04d}".format(name="id", value=7), "id:0007") + + def test_numeric_literal_and_float_roundtrip_behaviour_is_stable(self): + self.assertEqual(int("1_000_000"), 1000000) + self.assertEqual(int("ff", 16), 255) + value = float.fromhex("0x1.8p+2") + self.assertEqual(value.hex(), "0x1.8000000000000p+2") + + def test_sys_frame_metadata_for_regular_calls_is_stable(self): + def inner(): + frame = sys._getframe() + return frame.f_code.co_name, frame.f_globals["__name__"] + + self.assertEqual(inner(), ("inner", __name__)) + + +if __name__ == "__main__": + unittest.main()