1#!/usr/bin/env python
2#
3#===- clang-format-diff.py - ClangFormat Diff Reformatter ----*- python -*--===#
4#
5# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
6# See https://llvm.org/LICENSE.txt for license information.
7# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
8#
9#===------------------------------------------------------------------------===#
10
11"""
12This script reads input from a unified diff and reformats all the changed
13lines. This is useful to reformat all the lines touched by a specific patch.
14Example usage for git/svn users:
15
16  git diff -U0 --no-color HEAD^ | clang-format-diff.py -p1 -i
17  svn diff --diff-cmd=diff -x-U0 | clang-format-diff.py -i
18
19"""
20from __future__ import absolute_import, division, print_function
21
22import argparse
23import difflib
24import re
25import subprocess
26import sys
27
28if sys.version_info.major >= 3:
29    from io import StringIO
30else:
31    from io import BytesIO as StringIO
32
33
34def main():
35  parser = argparse.ArgumentParser(description=__doc__,
36                                   formatter_class=
37                                           argparse.RawDescriptionHelpFormatter)
38  parser.add_argument('-i', action='store_true', default=False,
39                      help='apply edits to files instead of displaying a diff')
40  parser.add_argument('-p', metavar='NUM', default=0,
41                      help='strip the smallest prefix containing P slashes')
42  parser.add_argument('-regex', metavar='PATTERN', default=None,
43                      help='custom pattern selecting file paths to reformat '
44                      '(case sensitive, overrides -iregex)')
45  parser.add_argument('-iregex', metavar='PATTERN', default=
46                      r'.*\.(cpp|cc|c\+\+|cxx|c|cl|h|hh|hpp|m|mm|inc|js|ts|proto'
47                      r'|protodevel|java|cs)',
48                      help='custom pattern selecting file paths to reformat '
49                      '(case insensitive, overridden by -regex)')
50  parser.add_argument('-sort-includes', action='store_true', default=False,
51                      help='let clang-format sort include blocks')
52  parser.add_argument('-v', '--verbose', action='store_true',
53                      help='be more verbose, ineffective without -i')
54  parser.add_argument('-style',
55                      help='formatting style to apply (LLVM, Google, Chromium, '
56                      'Mozilla, WebKit)')
57  parser.add_argument('-binary', default='clang-format',
58                      help='location of binary to use for clang-format')
59  args = parser.parse_args()
60
61  # Extract changed lines for each file.
62  filename = None
63  lines_by_file = {}
64  for line in sys.stdin:
65    match = re.search(r'^\+\+\+\ (.*?/){%s}(\S*)' % args.p, line)
66    if match:
67      filename = match.group(2)
68    if filename == None:
69      continue
70
71    if args.regex is not None:
72      if not re.match('^%s$' % args.regex, filename):
73        continue
74    else:
75      if not re.match('^%s$' % args.iregex, filename, re.IGNORECASE):
76        continue
77
78    match = re.search(r'^@@.*\+(\d+)(,(\d+))?', line)
79    if match:
80      start_line = int(match.group(1))
81      line_count = 1
82      if match.group(3):
83        line_count = int(match.group(3))
84      if line_count == 0:
85        continue
86      end_line = start_line + line_count - 1
87      lines_by_file.setdefault(filename, []).extend(
88          ['-lines', str(start_line) + ':' + str(end_line)])
89
90  # Reformat files containing changes in place.
91  for filename, lines in lines_by_file.items():
92    if args.i and args.verbose:
93      print('Formatting {}'.format(filename))
94    command = [args.binary, filename]
95    if args.i:
96      command.append('-i')
97    if args.sort_includes:
98      command.append('-sort-includes')
99    command.extend(lines)
100    if args.style:
101      command.extend(['-style', args.style])
102    p = subprocess.Popen(command,
103                         stdout=subprocess.PIPE,
104                         stderr=None,
105                         stdin=subprocess.PIPE,
106                         universal_newlines=True)
107    stdout, stderr = p.communicate()
108    if p.returncode != 0:
109      sys.exit(p.returncode)
110
111    if not args.i:
112      with open(filename) as f:
113        code = f.readlines()
114      formatted_code = StringIO(stdout).readlines()
115      diff = difflib.unified_diff(code, formatted_code,
116                                  filename, filename,
117                                  '(before formatting)', '(after formatting)')
118      diff_string = ''.join(diff)
119      if len(diff_string) > 0:
120        sys.stdout.write(diff_string)
121
122if __name__ == '__main__':
123  main()
124