#!/usr/bin/env python3
"""Check only type_new_set_doc's doc_str declaration and conversion timing."""
import re
from pathlib import Path

source = Path("cpython/Objects/typeobject.c").read_text()
match = re.search(
    r"\nstatic int\ntype_new_set_doc\(PyTypeObject \*type\)\n\{(.*?)\n\}",
    source,
    re.S,
)
assert match, "type_new_set_doc definition missing"
body = re.sub(r"/\*.*?\*/|//[^\n]*", "", match.group(1), flags=re.S)
assert re.match(
    r"\s*const char \*doc_str;"
    r"\s*Py_ssize_t size;"
    r"\s*char \*tp_doc;"
    r"\s*PyObject \*doc = PyDict_GetItemWithError"
    r"\(type->tp_dict, &_Py_ID\(__doc__\)\);",
    body,
), "type_new_set_doc: doc_str and size must be in the opening declaration block (C89)"
assert len(re.findall(r"\bconst\s+char\s*\*\s*doc_str\b", body)) == 1, (
    "declare doc_str exactly once"
)
assert len(re.findall(r"\bdoc_str\s*=(?!=)", body)) == 1, (
    "assign doc_str exactly once"
)
expected = """
    const char *doc_str;
    Py_ssize_t size;
    char *tp_doc;
    PyObject *doc = PyDict_GetItemWithError(type->tp_dict, &_Py_ID(__doc__));
    if (doc == NULL) {
        if (PyErr_Occurred()) {
            return -1;
        }
        return 0;
    }
    if (!PyUnicode_Check(doc)) {
        return 0;
    }

    doc_str = PyUnicode_AsUTF8(doc);
    if (doc_str == NULL) {
        return -1;
    }

    size = strlen(doc_str) + 1;
    tp_doc = (char *)PyObject_Malloc(size);
    if (tp_doc == NULL) {
        PyErr_NoMemory();
        return -1;
    }

    memcpy(tp_doc, doc_str, size);
    type->tp_doc = tp_doc;
    return 0;
"""
assert body.split() == expected.split(), (
    "type_new_set_doc: preserve conversion timing, early returns, allocation, "
    "and docstring copy; leave other declarations unchanged"
)
print("type_new_set_doc doc_str C89 declaration and conversion timing: PASS")