#!/usr/bin/env python3
"""Regress type_new_slots_impl C89 declaration and assignment timing."""
import re
from pathlib import Path

source = Path("cpython/Objects/typeobject.c").read_text()
match = re.search(
    r"\nstatic int\ntype_new_slots_impl\(type_new_ctx \*ctx, PyObject \*dict\)\n\{(.*?)\n\}",
    source,
    re.S,
)
assert match, "type_new_slots_impl definition missing"
body = re.sub(r"/\*.*?\*/|//[^\n]*", "", match.group(1), flags=re.S)
assert re.match(
    r"\s*PyObject \*new_slots;\s*if \(ctx->nslot > 0 && ctx->base->tp_itemsize != 0\)",
    body,
), "type_new_slots_impl: new_slots must be in the opening declaration block (C89)"
assert re.search(
    r'PyErr_Format\(PyExc_TypeError,\s*'
    r'"nonempty __slots__ not supported for subtype of \'%s\'",\s*'
    r"ctx->base->tp_name\);\s*return -1;\s*\}"
    r"\s*if \(type_new_visit_slots\(ctx\) < 0\) \{\s*return -1;\s*\}"
    r"\s*new_slots = type_new_copy_slots\(ctx, dict\);"
    r"\s*if \(new_slots == NULL\) \{\s*return -1;\s*\}"
    r"\s*assert\(PyTuple_CheckExact\(new_slots\)\);"
    r"\s*Py_XSETREF\(ctx->slots, new_slots\);"
    r"\s*ctx->nslot = PyTuple_GET_SIZE\(new_slots\);"
    r"\s*type_new_slots_bases\(ctx\);\s*return 0;\s*$",
    body,
), "preserve validation, copying, error checks, ownership transfer and secondary-base order"
assert len(re.findall(r"PyObject \*new_slots\b", body)) == 1, "declare new_slots exactly once"
print("type_new_slots_impl C89 declaration and assignment timing: PASS")