gh-144957: Add test for lazy imports with __getattr__

[gourijain029-del]

Adds a regression test for lazy imports working with modules that use __getattr__.

The issue reported that lazy from typing import Match would fail since Match is provided by typing.__getattr__ rather than being in the module dict. Testing shows this works correctly in current main - the existing code in register_lazy_on_parent() already checks for __getattr__ and skips adding lazy import objects to those modules.

This test documents the expected behavior and prevents future regressions.

• Issue: PEP 810 lazy from imports ignore module __getattr__ when reifying #144957

[bedevere-app]

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[johnslavik]

Testing shows this works correctly in current main - the existing code in register_lazy_on_parent() already checks for __getattr__ and skips adding lazy import objects to those modules.

Your test doesn't pass locally for me:

❯ ./python.exe-munittestLib.test.test_import.test_lazy_imports
....................................................F............BAR_MODULE_LOADED
...........................
======================================================================FAIL: test_lazy_import_with_getattr (Lib.test.test_import.test_lazy_imports.LazyImportTests.test_lazy_import_with_getattr)
Lazyimportsworkwithmodule__getattr__ (gh-144957).
----------------------------------------------------------------------Traceback (mostrecentcalllast):
File"/Users/bartosz.slawecki/Python/cpython/Lib/test/test_import/test_lazy_imports.py", line101, intest_lazy_import_with_getattrself.assertEqual(result.returncode, 0, result.stderr)
~~~~~~~~~~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^AssertionError: 1!=0 : Traceback (mostrecentcalllast):
File"<string>", line4, in<module>ImportError: deferredimportof'typing.Match'raisedanexceptionduringresolutionTheaboveexceptionwasthedirectcauseofthefollowingexception:
Traceback (mostrecentcalllast):
File"<string>", line5, in<module>print(Match)
^^^^^ImportError: cannotimportname'Match'from'typing' (/Users/bartosz.slawecki/Python/cpython/Lib/typing.py)

Presumably there's something with CI, needs investigation.
EDIT: See #145334.

[johnslavik]

Less prone to false positives:

Suggested change

	code=textwrap.dedent("""
	importsys
	sys.set_lazy_imports("normal")
	lazyfromtest.test_import.data.lazy_imports.module_with_getattrimportdynamic_attr
	assertdynamic_attr=="from_getattr"
	print("OK")
	""")
	result=subprocess.run(
	[sys.executable, "-c", code],
	capture_output=True,
	text=True
	)
	self.assertEqual(result.returncode, 0, result.stderr)
	self.assertIn("OK", result.stdout)
	code=textwrap.dedent("""
	importsys
	sys.set_lazy_imports("normal")
	lazyfromtest.test_lazy_import.data.module_with_getattrimportdynamic_attr
	print(repr(dynamic_attr))
	""")
	result=subprocess.run(
	[sys.executable, "-c", code],
	capture_output=True,
	text=True
	)
	self.assertEqual(result.returncode, 0, result.stderr)
	self.assertIn("'from_getattr'", result.stdout)

[pablogsal]

This user is creating a lot of AI generated PRs see #145276