#!/usr/bin/env python3
"""Guard _PyMem_GetCurrentAllocatorName C89 local placement and comparisons."""

import re
import sys
from pathlib import Path

source = Path(sys.argv[1]).read_text()
match = re.search(
    r"_PyMem_GetCurrentAllocatorName\s*\([^)]*\)\s*\{(?P<body>.*?)\n\}",
    source,
    re.S,
)
assert match, "_PyMem_GetCurrentAllocatorName definition not found"
body = match.group("body")

expected_declarations = [
    "PyMemAllocatorEx malloc_alloc = MALLOC_ALLOC;",
    "PyMemAllocatorEx pymalloc = PYMALLOC_ALLOC;",
    "PyMemAllocatorEx dbg_raw = PYDBGRAW_ALLOC;",
    "PyMemAllocatorEx dbg_mem = PYDBGMEM_ALLOC;",
    "PyMemAllocatorEx dbg_obj = PYDBGOBJ_ALLOC;",
]
positions = [body.find(declaration) for declaration in expected_declarations]
assert all(position >= 0 for position in positions), "allocator snapshot declarations must remain present"
first_check = body.find("if (pymemallocator_eq")
assert first_check >= 0 and positions == sorted(positions) and positions[-1] < first_check, (
    "all allocator snapshots must be initialized before the first statement for C89"
)
assert body.count("if (pymemallocator_eq(&_PyMem_Raw, &malloc_alloc)") == 2, (
    "preserve the malloc and pymalloc base-allocator comparisons"
)
assert body.count("if (pymemallocator_eq(&_PyMem_Debug.raw.alloc, &malloc_alloc) &&") == 2, (
    "preserve malloc_debug and pymalloc_debug allocator comparisons"
)
assert "pymemallocator_eq(&_PyMem_Raw, &dbg_raw)" in body
assert "pymemallocator_eq(&_PyMem, &dbg_mem)" in body
assert "pymemallocator_eq(&_PyObject, &dbg_obj)" in body
assert body.index("/* Debug hooks installed */") < body.index('return "malloc_debug";')
assert body.index('return "malloc_debug";') < body.index('return "pymalloc_debug";')
assert body.index('return "pymalloc_debug";') < body.index("return NULL;")
print("obmalloc allocator-name C89 declarations and allocator classification order: PASS")