diff --git a/Lib/test/test_pep709_aug.py b/Lib/test/test_pep709_aug.py new file mode 100644 --- /dev/null +++ b/Lib/test/test_pep709_aug.py @@ -0,0 +1,305 @@ +import asyncio +import dis +import importlib.util +import opcode +import pathlib +import sys +import symtable +import types +import unittest +import weakref + + +def nested_code_names(code): + names = [] + for const in code.co_consts: + if isinstance(const, types.CodeType): + names.append(const.co_name) + names.extend(nested_code_names(const)) + return names + + +def assert_no_comprehension_code(testcase, func): + testcase.assertFalse( + any(name in {"", "", ""} for name in nested_code_names(func.__code__)), + nested_code_names(func.__code__), + ) + + +class InlinedComprehensionAugmentedTests(unittest.TestCase): + def test_opcode_tables_and_parent_bytecode_show_inlined_comprehensions(self): + def f(values): + return [x + 1 for x in values if x % 2] + + assert_no_comprehension_code(self, f) + instructions = [instr.opname for instr in dis.get_instructions(f)] + self.assertIn("LOAD_FAST_AND_CLEAR", instructions) + self.assertIn("LIST_APPEND", instructions) + self.assertNotIn("MAKE_FUNCTION", instructions) + + load_fast_and_clear = opcode.opmap["LOAD_FAST_AND_CLEAR"] + self.assertIn(load_fast_and_clear, opcode.haslocal) + self.assertEqual(opcode.opname[load_fast_and_clear], "LOAD_FAST_AND_CLEAR") + + def test_inlined_comprehension_locals_are_restored_and_hidden(self): + def f(): + x = "outer" + values = [x for x in range(3)] + after = locals().copy() + return x, values, after + + assert_no_comprehension_code(self, f) + x, values, after = f() + self.assertEqual(x, "outer") + self.assertEqual(values, [0, 1, 2]) + self.assertNotEqual(after.get("x"), 2) + + def no_outer_binding(): + [hidden_name for hidden_name in range(2)] + return locals().copy() + + assert_no_comprehension_code(self, no_outer_binding) + self.assertNotIn("hidden_name", no_outer_binding()) + + def test_traceback_and_profile_do_not_report_comprehension_frames(self): + def failing(): + return [1 // x for x in [0]] + + assert_no_comprehension_code(self, failing) + try: + failing() + except ZeroDivisionError as exc: + names = [] + tb = exc.__traceback__ + while tb is not None: + names.append(tb.tb_frame.f_code.co_name) + tb = tb.tb_next + else: + self.fail("expected ZeroDivisionError") + self.assertNotIn("", names) + + events = [] + + def profiler(frame, event, arg): + if event in {"call", "return"}: + events.append((event, frame.f_code.co_name)) + + def profiled(values): + return {x * 2 for x in values} + + assert_no_comprehension_code(self, profiled) + old_profile = sys.getprofile() + sys.setprofile(profiler) + try: + self.assertEqual(profiled([1, 2]), {2, 4}) + finally: + sys.setprofile(old_profile) + self.assertNotIn(("call", ""), events) + self.assertNotIn(("return", ""), events) + + def test_global_cell_and_freevar_targets_preserve_isolation(self): + global pep709_global_target + pep709_global_target = "global" + + def global_target(): + global pep709_global_target + values = [pep709_global_target for pep709_global_target in range(3)] + return values, pep709_global_target + + assert_no_comprehension_code(self, global_target) + self.assertEqual(global_target(), ([0, 1, 2], "global")) + + def outer(): + cell_target = "cell" + + def reader(): + return cell_target + + values = [cell_target for cell_target in range(2)] + return cell_target, reader(), values + + assert_no_comprehension_code(self, outer) + self.assertEqual(outer(), ("cell", "cell", [0, 1])) + + def test_async_comprehensions_are_inlined_and_use_async_iteration(self): + async def agen(): + for value in range(3): + yield value + + async def f(): + return [x + 10 async for x in agen()], {x async for x in agen()}, { + x: x * 2 async for x in agen() + } + + assert_no_comprehension_code(self, f) + result = asyncio.run(f()) + self.assertEqual(result, ([10, 11, 12], {0, 1, 2}, {0: 0, 1: 2, 2: 4})) + + instructions = [instr.opname for instr in dis.get_instructions(f)] + self.assertIn("GET_AITER", instructions) + self.assertIn("LIST_APPEND", instructions) + self.assertIn("SET_ADD", instructions) + self.assertIn("MAP_ADD", instructions) + + def test_nested_list_and_tuple_subiterators_are_inlined(self): + def f(values): + return [ + (x, y, z) + for x in values + for y in [x + 1] + for z in (y + 1,) + ] + + assert_no_comprehension_code(self, f) + self.assertEqual(f([1, 3]), [(1, 2, 3), (3, 4, 5)]) + + def list_subiterator(values): + return [(x, y) for x in values for y in [x + 1, x + 2]] + + assert_no_comprehension_code(self, list_subiterator) + self.assertEqual(list_subiterator([1, 3]), [(1, 2), (1, 3), (3, 4), (3, 5)]) + + instructions = [instr.opname for instr in dis.get_instructions(f)] + self.assertIn("LOAD_FAST_AND_CLEAR", instructions) + self.assertIn("LIST_APPEND", instructions) + + def test_nested_async_subiterator_is_inlined(self): + async def agen(values): + for value in values: + yield value + + async def f(): + return [ + (x, y) + async for x in agen([1, 2]) + async for y in agen([x + 10]) + ] + + assert_no_comprehension_code(self, f) + self.assertEqual(asyncio.run(f()), [(1, 11), (2, 12)]) + + instructions = [instr.opname for instr in dis.get_instructions(f)] + self.assertIn("GET_AITER", instructions) + self.assertIn("LIST_APPEND", instructions) + + def test_magic_number_marks_new_inlined_comprehension_bytecode(self): + self.assertEqual( + importlib.util.MAGIC_NUMBER[:2], + (3529).to_bytes(2, "little"), + ) + + def test_locals_inside_comprehension_include_outer_values(self): + def f(): + outer_value = "available" + snapshots = [locals().copy() for _ in range(1)] + return snapshots[0] + + assert_no_comprehension_code(self, f) + snapshot = f() + self.assertEqual(snapshot.get("outer_value"), "available") + + def test_module_and_class_scope_locals_hide_temporary_fast_locals(self): + module_source = """ +x = "outer" +snapshots = [locals().copy().get("x") for x in range(2)] +after = locals().copy().get("x") +""" + module_code = compile(module_source, "", "exec") + self.assertNotIn("", nested_code_names(module_code)) + namespace = {} + exec(module_code, namespace) + self.assertEqual(namespace["snapshots"], ["outer", "outer"]) + self.assertEqual(namespace["after"], "outer") + + class_source = """ +class C: + x = "outer" + snapshots = [locals().copy().get("x") for x in range(2)] + after = locals().copy().get("x") +""" + class_code = compile(class_source, "", "exec") + self.assertNotIn("", nested_code_names(class_code)) + class_namespace = {} + exec(class_code, class_namespace) + cls = class_namespace["C"] + self.assertEqual(cls.snapshots, ["outer", "outer"]) + self.assertEqual(cls.after, "outer") + + def test_shadowed_outer_object_is_restored_and_outer_reads_stay_fast(self): + class Watch: + pass + + def restores_object(): + x = Watch() + ref = weakref.ref(x) + values = [x for x in range(2)] + return values, isinstance(x, Watch), ref() is x, ref() is not None + + assert_no_comprehension_code(self, restores_object) + self.assertEqual(restores_object(), ([0, 1], True, True, True)) + + def reads_outer_fast(): + outer = 10 + return [outer + x for x in range(2)] + + assert_no_comprehension_code(self, reads_outer_fast) + self.assertEqual(reads_outer_fast(), [10, 11]) + self.assertEqual(reads_outer_fast.__code__.co_cellvars, ()) + self.assertIn("outer", reads_outer_fast.__code__.co_varnames) + + def test_module_scope_name_is_restored_after_comprehension(self): + source = """ +x = "outer" +values = [x for x in range(2)] +y = x +""" + code = compile(source, "", "exec") + self.assertNotIn("", nested_code_names(code)) + namespace = {} + exec(code, namespace) + self.assertEqual(namespace["values"], [0, 1]) + self.assertEqual(namespace["x"], "outer") + self.assertEqual(namespace["y"], "outer") + + def test_assembler_fasthidden_metadata_hides_fast_local_from_locals(self): + def uses_hidden_local(): + [hidden for hidden in range(3)] + return locals().copy() + + assert_no_comprehension_code(self, uses_hidden_local) + # PEP 709 inlines the comprehension: its iteration variable becomes a + # real, named fast-local slot of the enclosing code object ... + self.assertIn("hidden", uses_hidden_local.__code__.co_varnames) + # ... but that temporary is hidden from the enclosing frame's locals(). + self.assertNotIn("hidden", uses_hidden_local()) + + def test_nested_comprehension_children_are_spliced_into_parent_symtable(self): + source = """ +def f(): + outer = 10 + return [(lambda: outer + x)() for x in range(2)] +""" + table = symtable.symtable(source, "", "exec") + function_table = next(child for child in table.get_children() if child.get_name() == "f") + child_names = [child.get_name() for child in function_table.get_children()] + self.assertEqual(child_names, ["lambda"]) + + def test_cellvar_targets_are_recreated_for_lambdas_inside_comprehensions(self): + def f(): + x = "outer" + funcs = [(lambda: x) for x in range(2)] + return x, [func() for func in funcs] + + assert_no_comprehension_code(self, f) + self.assertEqual(f(), ("outer", [1, 1])) + + def test_debug_opcode_metadata_names_load_fast_and_clear(self): + root = pathlib.Path(__file__).resolve().parents[2] + opcode_header = root / "Include" / "internal" / "pycore_opcode.h" + text = opcode_header.read_text(encoding="utf-8") + self.assertIn("[LOAD_FAST_AND_CLEAR] = LOAD_FAST_AND_CLEAR", text) + self.assertIn('[LOAD_FAST_AND_CLEAR] = "LOAD_FAST_AND_CLEAR"', text) + + +if __name__ == "__main__": + unittest.main() diff --git a/Lib/test/test_pep709_stability_aug.py b/Lib/test/test_pep709_stability_aug.py new file mode 100644 --- /dev/null +++ b/Lib/test/test_pep709_stability_aug.py @@ -0,0 +1,37 @@ +import unittest + + +class InlinedComprehensionStabilityAugmentedTests(unittest.TestCase): + def test_comprehension_results_and_iteration_variable_isolation_are_stable(self): + x = "outer" + values = [x * 2 for x in range(4) if x % 2] + self.assertEqual(values, [2, 6]) + self.assertEqual(x, "outer") + + self.assertEqual({x for x in [1, 1, 2]}, {1, 2}) + self.assertEqual({x: x * x for x in range(3)}, {0: 0, 1: 1, 2: 4}) + + def test_nested_comprehension_semantics_are_stable(self): + pairs = [(x, y) for x in range(3) for y in range(x)] + self.assertEqual(pairs, [(1, 0), (2, 0), (2, 1)]) + + def test_generator_expressions_keep_lazy_behavior(self): + calls = [] + + def source(): + for value in range(3): + calls.append(value) + yield value + + gen = (value * 10 for value in source()) + self.assertEqual(calls, []) + self.assertEqual(next(gen), 0) + self.assertEqual(calls, [0]) + + def test_exception_behavior_inside_comprehension_is_stable(self): + with self.assertRaises(ZeroDivisionError): + [1 // x for x in [1, 0, 2]] + + +if __name__ == "__main__": + unittest.main()