xref: /aosp_15_r20/tools/repohooks/tools/clang-format.py (revision d68f33bc6fb0cc2476107c2af0573a2f5a63dfc1)
1#!/usr/bin/env python3
2# Copyright 2016 The Android Open Source Project
3#
4# Licensed under the Apache License, Version 2.0 (the "License");
5# you may not use this file except in compliance with the License.
6# You may obtain a copy of the License at
7#
8#      http://www.apache.org/licenses/LICENSE-2.0
9#
10# Unless required by applicable law or agreed to in writing, software
11# distributed under the License is distributed on an "AS IS" BASIS,
12# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13# See the License for the specific language governing permissions and
14# limitations under the License.
15
16"""Wrapper to run git-clang-format and parse its output."""
17
18import argparse
19import os
20import sys
21
22_path = os.path.realpath(__file__ + '/../..')
23if sys.path[0] != _path:
24    sys.path.insert(0, _path)
25del _path
26
27# We have to import our local modules after the sys.path tweak.  We can't use
28# relative imports because this is an executable program, not a module.
29# pylint: disable=wrong-import-position,import-error
30import rh.shell
31import rh.utils
32
33
34# Since we're asking git-clang-format to print a diff, all modified filenames
35# that have formatting errors are printed with this prefix.
36DIFF_MARKER_PREFIX = '+++ b/'
37
38
39def get_parser():
40    """Return a command line parser."""
41    parser = argparse.ArgumentParser(description=__doc__)
42    parser.add_argument('--clang-format', default='clang-format',
43                        help='The path of the clang-format executable.')
44    parser.add_argument('--git-clang-format', default='git-clang-format',
45                        help='The path of the git-clang-format executable.')
46    parser.add_argument('--style', metavar='STYLE', type=str,
47                        help='The style that clang-format will use.')
48    parser.add_argument('--extensions', metavar='EXTENSIONS', type=str,
49                        help='Comma-separated list of file extensions to '
50                             'format.')
51    parser.add_argument('--fix', action='store_true',
52                        help='Fix any formatting errors automatically.')
53
54    scope = parser.add_mutually_exclusive_group(required=True)
55    scope.add_argument('--commit', type=str, default='HEAD',
56                       help='Specify the commit to validate.')
57    scope.add_argument('--working-tree', action='store_true',
58                       help='Validates the files that have changed from '
59                            'HEAD in the working directory.')
60
61    parser.add_argument('files', type=str, nargs='*',
62                        help='If specified, only consider differences in '
63                             'these files.')
64    return parser
65
66
67def main(argv):
68    """The main entry."""
69    parser = get_parser()
70    opts = parser.parse_args(argv)
71
72    cmd = [opts.git_clang_format, '--binary', opts.clang_format, '--diff']
73    if opts.style:
74        cmd.extend(['--style', opts.style])
75    if opts.extensions:
76        cmd.extend(['--extensions', opts.extensions])
77    if not opts.working_tree:
78        cmd.extend([f'{opts.commit}^', opts.commit])
79    cmd.extend(['--'] + opts.files)
80
81    # Fail gracefully if clang-format itself aborts/fails.
82    result = rh.utils.run(cmd, capture_output=True, check=False)
83    # Newer versions of git-clang-format will exit 1 when it worked.  Assume a
84    # real failure is any exit code above 1, or any time stderr is used, or if
85    # it exited 1 and produce useful format diffs to stdout.  If it exited 0,
86    # then assume all is well and we'll attempt to parse its output below.
87    ret_code = None
88    if (result.returncode > 1 or result.stderr or
89        (result.stdout and result.returncode)):
90        # Apply fix if the flag is set and clang-format shows it is fixible.
91        if opts.fix and result.stdout and result.returncode:
92            result = rh.utils.run(['git', 'apply'], input=result.stdout,
93                                   check=False)
94            ret_code = result.returncode
95            if ret_code:
96                print('Error: Unable to automatically fix things.\n'
97                      '  Make sure your checkout is clean first.\n'
98                      '  If you have multiple commits, you might have to '
99                      'manually rebase your tree first.',
100                      file=sys.stderr)
101
102        else:  # Regular clang-format aborts/fails.
103            print(f'clang-format failed:\ncmd: {result.cmdstr}\n'
104                  f'stdout:\n{result.stdout}\n', file=sys.stderr)
105            if result.returncode > 1 or result.stderr:
106                print('\nPlease report this to the clang team.\n',
107                      f'stderr:\n{result.stderr}', file=sys.stderr)
108            ret_code = 1
109
110        return ret_code
111
112    stdout = result.stdout
113    if stdout.rstrip('\n') == 'no modified files to format':
114        # This is always printed when only files that clang-format does not
115        # understand were modified.
116        return 0
117
118    diff_filenames = []
119    for line in stdout.splitlines():
120        if line.startswith(DIFF_MARKER_PREFIX):
121            diff_filenames.append(line[len(DIFF_MARKER_PREFIX):].rstrip())
122
123    if diff_filenames:
124        if opts.fix:
125            result = rh.utils.run(['git', 'apply'], input=stdout, check=False)
126            if result.returncode:
127                print('Error: Unable to automatically fix things.\n'
128                      '  Make sure your checkout is clean first.\n'
129                      '  If you have multiple commits, you might have to '
130                      'manually rebase your tree first.',
131                      file=sys.stderr)
132                return result.returncode
133        else:
134            print('The following files have formatting errors:')
135            for filename in diff_filenames:
136                print(f'\t{filename}')
137            print('You can try to fix this by running:\n'
138                  f'{sys.argv[0]} --fix {rh.shell.cmd_to_str(argv)}')
139            return 1
140
141    return 0
142
143
144if __name__ == '__main__':
145    sys.exit(main(sys.argv[1:]))
146