format_util.py

#!/usr/bin/env python3

# Copyright Amazon.com, Inc. or its affiliates. All Rights Reserved.
# SPDX-License-Identifier: Apache-2.0.

"""
Utility for formatting generated C++ code using clang-format
"""
import os
import pathlib
import re
import subprocess
from subprocess import list2cmdline, run
from tempfile import NamedTemporaryFile

CLANG_FORMAT_VERSION = '18.1.6'
CLANG_FORMAT_INCLUDE_REGEX = re.compile(r'^.*\.(cpp|h)$')

def format_directories(directory_list):
    """Format C++ files in the given directories using clang-format"""
    cpu_count = os.cpu_count() or 1

    filepaths_files = [NamedTemporaryFile(delete=False) for _ in range(cpu_count)]

    index = 0
    for root_dir in directory_list:
        if os.path.exists(root_dir):
            for dirpath, dirnames, filenames in os.walk(root_dir):
                for filename in filenames:
                    filepath = pathlib.Path(dirpath, filename).as_posix()
                    if CLANG_FORMAT_INCLUDE_REGEX.match(filename):
                        filepaths_files[index % cpu_count].write(f"{filepath}\n".encode())
                        index += 1

    for filepaths_file in filepaths_files:
        filepaths_file.close()

    processes = []
    for filepaths_file in filepaths_files:
        cmd = ['pipx', 'run', f'clang-format=={CLANG_FORMAT_VERSION}',
               f'--files={filepaths_file.name}', '-i', '-style=file:.clang-format']
        p = subprocess.Popen(cmd)
        processes.append(p)
        print(f"Formatting generated files: {list2cmdline(cmd)}")

    for p in processes:
        p.wait()

    # Clean up temp file
    for filepaths_file in filepaths_files:
        os.unlink(filepaths_file.name)