gh-133516: Raise ValueError when constants True, False or None are used as an identifier after NFKC normalization

[TERESH1]

#133516

[python-cla-bot]

All commit authors signed the Contributor License Agreement.

[pablogsal]

LGTM

[ZeroIntensity]

Formatting silliness

[ZeroIntensity]

Actually, wait a minute--@pablogsal, could you reproduce this on main or 3.13? I can't with either the test case or the reproducer provided in the issue. I don't see how this could possibly be platform-dependent.

[pablogsal]

Actually, wait a minute--@pablogsal, could you reproduce this on main or 3.13? I can't with either the test case or the reproducer provided in the issue. I don't see how this could possibly be platform-dependent.

Humm good point. In macOS I am seeing this:

Python 3.14.0a7+ (heads/main-dirty:3dfed230928, May  6 2025, 16:15:52) [Clang 17.0.0 (clang-1700.0.13.3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> compile(source=b'Fal\xc5\xbfe', filename="<test>", mode="exec")
Traceback (most recent call last):
  File "<python-input-0>", line 1, in <module>
    compile(source=b'Fal\xc5\xbfe', filename="<test>", mode="exec")
    ~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: identifier field can't represent 'False' constant

[pablogsal]

Is hitting this assert:

cpython/Python/codegen.c

Line 3187 in a4be3bc

assert(!_PyUnicode_EqualToASCIIString(name, "None") &&

maybe we don't have asserts compiled in? But debug mode should not optimize them away....

[TERESH1]

Actually, wait a minute--@pablogsal, could you reproduce this on main or 3.13? I can't with either the test case or the reproducer provided in the issue. I don't see how this could possibly be platform-dependent.

Humm good point. In macOS I am seeing this:

Python 3.14.0a7+ (heads/main-dirty:3dfed230928, May  6 2025, 16:15:52) [Clang 17.0.0 (clang-1700.0.13.3)] on darwin
Type "help", "copyright", "credits" or "license" for more information.
>>> compile(source=b'Fal\xc5\xbfe', filename="<test>", mode="exec")
Traceback (most recent call last):
  File "<python-input-0>", line 1, in <module>
    compile(source=b'Fal\xc5\xbfe', filename="<test>", mode="exec")
    ~~~~~~~^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
ValueError: identifier field can't represent 'False' constant

Using Py_DEBUG, _PyAST_Validate is called after parsing AST

cpython/Parser/pegen.c

Lines 976 to 986 in 3dfed23

	// test_peg_generator defines _Py_TEST_PEGEN to not call PyAST_Validate()
	#if defined(Py_DEBUG) && !defined(_Py_TEST_PEGEN)
	if (p->start_rule == Py_single_input ||
	p->start_rule == Py_file_input ||
	p->start_rule == Py_eval_input)
	{
	if (!_PyAST_Validate(res)) {
	return NULL;
	}
	}
	#endif

But if only asserts are enabled, then there is no AST validation

[ZeroIntensity]

LGTM as well now

[miss-islington-app]

Thanks @TERESH1 for the PR, and @pablogsal for merging it 🌮🎉.. I'm working now to backport this PR to: 3.13.
🐍🍒⛏🤖

[miss-islington-app]

Sorry, @TERESH1 and @pablogsal, I could not cleanly backport this to 3.13 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker d9b0b07098ec4bdb47151948c77bcbbf3e796a5d 3.13

[miss-islington-app]

Thanks @TERESH1 for the PR, and @pablogsal for merging it 🌮🎉.. I'm working now to backport this PR to: 3.14.
🐍🍒⛏🤖

[bedevere-app]

GH-133596 is a backport of this pull request to the 3.14 branch.

[pablogsal]

Sorry, @TERESH1 and @pablogsal, I could not cleanly backport this to 3.13 due to a conflict.
Please backport using cherry_picker on command line.

cherry_picker d9b0b07098ec4bdb47151948c77bcbbf3e796a5d 3.13

@TERESH1 can you do the backpory following this instruction?

[bedevere-app]

GH-133615 is a backport of this pull request to the 3.13 branch.