#!/usr/bin/env python3
"""Check only structseq_repr's name_utf8 declaration and evaluation order."""
import re
import sys
from pathlib import Path

source = Path(sys.argv[1] if len(sys.argv) > 1 else "cpython/Objects/structseq.c")
match = re.search(
    r"static PyObject \*\nstructseq_repr\(PyStructSequence \*obj\)\n\{(.*?)\n\}",
    source.read_text(),
    re.S,
)
assert match, "structseq_repr definition not found"
body = match.group(1)
assert re.search(
    r"for \(i=0; i < VISIBLE_SIZE\(obj\); i\+\+\) \{"
    r"\s*const char \*name_utf8;\s*PyObject \*name;\s*if \(i > 0\)",
    body,
), "structseq_repr: VC6 requires name_utf8 declared before loop-body statements"
assert len(re.findall(r"const char \*name_utf8\b", body)) == 1, (
    "declare name_utf8 exactly once"
)
assert re.search(
    r'if \(i > 0\) \{\s*/\* Write ", " \*/\s*'
    r'if \(_PyUnicodeWriter_WriteASCIIString\(&writer, ", ", 2\) < 0\) '
    r'\{\s*goto error;\s*\}\s*\}\s*'
    r'/\* Write "name=repr" \*/\s*'
    r'name_utf8 = typ->tp_members\[i\].name;\s*'
    r'if \(name_utf8 == NULL\) \{\s*'
    r'PyErr_Format\(PyExc_SystemError, "In structseq_repr\(\), member %zd name is NULL"'
    r'\s*" for type %.500s", i, typ->tp_name\);\s*goto error;\s*\}\s*'
    r'name = PyUnicode_DecodeUTF8\(name_utf8, strlen\(name_utf8\), NULL\);',
    body,
), "preserve separator/error handling before member lookup, NULL check, and decoding"
assert len(re.findall(r"\bname_utf8\s*=", body)) == 2, (
    "preserve the single assignment and NULL comparison"
)
print("structseq_repr name_utf8 C89 declaration and evaluation order: PASS")