aboutsummaryrefslogtreecommitdiffstatshomepage
path: root/tools/clang-format.py
blob: 2f64a5e8e4d087bf877ddbbc3304555126dcbf01 (plain) (blame)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
#!/usr/bin/env python3

# Copyright (c) 2020 Egor Tensin <Egor.Tensin@gmail.com>
# This file is part of the "cmake-common" project.
# For details, see https://github.com/egor-tensin/cmake-common.
# Distributed under the MIT License.

'''Feed C/C++ files in the repository to clang-format

This script runs clang-format on every C/C++ file in the repository, either
printing a unified diff between the original and the formatted versions, or
formatting the files in-place.
'''

import argparse
from contextlib import contextmanager
import difflib
import logging
import os.path
import subprocess
import sys


@contextmanager
def _setup_logging():
    logging.basicConfig(
        format='%(asctime)s | %(levelname)s | %(message)s',
        datefmt='%Y-%m-%d %H:%M:%S',
        level=logging.INFO)
    try:
        yield
    except Exception as e:
        logging.exception(e)
        raise


def _run_executable(cmd_line):
    logging.debug('Running executable: %s', cmd_line)
    try:
        return subprocess.run(cmd_line, check=True, universal_newlines=True,
                              stderr=subprocess.STDOUT, stdout=subprocess.PIPE)
    except subprocess.CalledProcessError as e:
        logging.error('Process finished with exit code %d: %s', e.returncode, cmd_line)
        logging.error('Its output was:\n%s', e.output)
        raise


def _read_file(path):
    with open(path) as file:
        return file.read()


class ClangFormat:
    def __init__(self, path, style):
        self.path = path
        self.style = style

    def _get_command_line(self, paths, in_place=False):
        cmd_line = [self.path, f'-style={self.style}']
        if in_place:
            cmd_line.append('-i')
        cmd_line.append('--')
        cmd_line += list(paths)
        return cmd_line

    def format_in_place(self, paths):
        _run_executable(self._get_command_line(paths, in_place=True))

    @staticmethod
    def _show_diff(path, formatted):
        original = _read_file(path).split('\n')
        formatted = formatted.split('\n')
        original_lbl = f'{path} (original)'
        formatted_lbl = f'{path} (formatted)'

        diff = difflib.unified_diff(original, formatted, fromfile=original_lbl,
                                    tofile=formatted_lbl, lineterm='')

        clean = True
        for line in diff:
            clean = False
            print(line)
        return clean

    def show_diff(self, paths):
        clean = True
        for path in paths:
            formatted = _run_executable(self._get_command_line([path])).stdout
            clean = self._show_diff(path, formatted) and clean
        return clean


def _list_all_files():
    cmd_line = ['git', 'ls-tree', '-r', '-z', '--name-only', 'HEAD']
    repo_files = _run_executable(cmd_line).stdout
    repo_files = repo_files.split('\0')
    return repo_files


CPP_FILE_EXTENSIONS = {'.c', '.h', '.cc', '.hh', '.cpp', '.hpp', '.cxx', '.hxx', '.cp', '.c++'}


def _list_cpp_files():
    for path in _list_all_files():
        ext = os.path.splitext(path)[1]
        if ext in CPP_FILE_EXTENSIONS:
            yield path


def _process_cpp_files(args):
    clang_format = ClangFormat(args.clang_format, args.style)
    cpp_files = _list_cpp_files()
    if args.in_place:
        clang_format.format_in_place(cpp_files)
    else:
        if not clang_format.show_diff(cpp_files):
            sys.exit(1)


DEFAULT_CLANG_FORMAT = 'clang-format'
DEFAULT_STYLE = 'file'


def _parse_args(argv=None):
    if argv is None:
        argv = sys.argv[1:]

    parser = argparse.ArgumentParser(
        description=__doc__,
        formatter_class=argparse.RawDescriptionHelpFormatter)

    parser.add_argument('-b', '--clang-format', default=DEFAULT_CLANG_FORMAT,
                        help='clang-format executable file path')
    parser.add_argument('-s', '--style', default=DEFAULT_STYLE,
                        help='clang-format -style parameter argument')
    parser.add_argument('-i', '--in-place', action='store_true',
                        help='edit the files in-place')

    return parser.parse_args(argv)


def main(argv=None):
    with _setup_logging():
        args = _parse_args(argv)
        _process_cpp_files(args)


if __name__ == '__main__':
    main()