#!/usr/bin/env python3
"""Check NewType's C89 slot assignments and preserve all eight slot pairs."""
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"\n_PyStructSequence_NewType\([^\n]*\)\n\{.*?"
    r"/\* Initialize Slots \*/(.*?)/\* Initialize Spec \*/",
    source.read_text(),
    re.S,
)
assert match, "_PyStructSequence_NewType slots initialization not found"
body = match.group(1)
assert not re.search(r"\(\s*PyType_Slot\s*\)\s*\{", body), (
    "_PyStructSequence_NewType: compound-literal slot initializers are not C89 compatible"
)
pairs = [
    ("Py_tp_dealloc", "(destructor)structseq_dealloc"),
    ("Py_tp_repr", "(reprfunc)structseq_repr"),
    ("Py_tp_doc", "(void *)desc->doc"),
    ("Py_tp_methods", "structseq_methods"),
    ("Py_tp_new", "structseq_new"),
    ("Py_tp_members", "members"),
    ("Py_tp_traverse", "(traverseproc)structseq_traverse"),
    ("0", "0"),
]
expected = "\n".join(
    f"slots[{i}].slot = {slot}; slots[{i}].pfunc = {value};"
    for i, (slot, value) in enumerate(pairs)
)
assert re.sub(r"\s+", "", body) == re.sub(r"\s+", "", expected), (
    "preserve all slot values, ordering, casts, and the zero sentinel"
)
print("_PyStructSequence_NewType C89 slots, values, ordering, casts, and sentinel: PASS")