#!/usr/bin/env python3
"""Keep PyType_GetModuleByDef's loop index in opening C89 locals."""
import re
from pathlib import Path

source = Path("cpython/Objects/typeobject.c").read_text()
match = re.search(
    r"\nPyObject \*\nPyType_GetModuleByDef\(PyTypeObject \*type, PyModuleDef \*def\)\n"
    r"\{(.*?)\n\}", source, re.S,
)
assert match, "PyType_GetModuleByDef definition missing"
body = re.sub(r"/\*.*?\*/|//[^\n]*", "", match.group(1), flags=re.S)
assert re.match(r"\s*PyObject \*mro;\s*Py_ssize_t n;\s*Py_ssize_t i;\s*PyHeapTypeObject \*ht;\s*PyObject \*module;\s*assert\(", body), (
    "PyType_GetModuleByDef: i must be declared in the opening declaration block (C89)"
)
assert len(re.findall(r"\bPy_ssize_t\s+i\b", body)) == 1, (
    "PyType_GetModuleByDef: declare i exactly once"
)
expected = """
    PyObject *mro;
    Py_ssize_t n;
    Py_ssize_t i;
    PyHeapTypeObject *ht;
    PyObject *module;
    assert(PyType_Check(type));

    mro = type->tp_mro;
    assert(mro != NULL);
    assert(PyTuple_Check(mro));
    assert(PyTuple_GET_SIZE(mro) >= 1);

    n = PyTuple_GET_SIZE(mro);
    for (i = 0; i < n; i++) {
        PyObject *super = PyTuple_GET_ITEM(mro, i);
        if(!_PyType_HasFeature((PyTypeObject *)super, Py_TPFLAGS_HEAPTYPE)) {
            continue;
        }

        ht = (PyHeapTypeObject*)super;
        module = ht->ht_module;
        if (module && _PyModule_GetDef(module) == def) {
            return module;
        }
    }

    PyErr_Format(
        PyExc_TypeError,
        "PyType_GetModuleByDef: No superclass of '%s' has the given module",
        type->tp_name);
    return NULL;
"""
assert body.split() == expected.split(), (
    "PyType_GetModuleByDef: preserve loop initialization, bound, increment, body, and surrounding "
    "loop, module lookup, and error handling"
)
print("PyType_GetModuleByDef C89 loop index and preserved loop semantics: PASS")