xref: /llvm-project/clang/tools/clang-format/clang-format-diff.py (revision f886c03e47092d1fad1998df0ddfcffa9e8c3d48) 
1#!/usr/bin/env python
2#
3#===- clang-format-diff.py - ClangFormat Diff Reformatter ----*- python -*--===#
4#
5#                     The LLVM Compiler Infrastructure
6#
7# This file is distributed under the University of Illinois Open Source
8# License. See LICENSE.TXT for details.
9#
10#===------------------------------------------------------------------------===#
11
12r"""
13ClangFormat Diff Reformatter
14============================
15
16This script reads input from a unified diff and reformats all the changed
17lines. This is useful to reformat all the lines touched by a specific patch.
18Example usage for git/svn users:
19
20  git diff -U0 --no-color HEAD^ | clang-format-diff.py -p1 -i
21  svn diff --diff-cmd=diff -x-U0 | clang-format-diff.py -i
22
23"""
24from __future__ import absolute_import, division, print_function
25
26import argparse
27import difflib
28import re
29import subprocess
30import sys
31
32if sys.version_info.major >= 3:
33    from io import StringIO
34else:
35    from io import BytesIO as StringIO
36
37
38def main():
39  parser = argparse.ArgumentParser(description=
40                                   'Reformat changed lines in diff. Without -i '
41                                   'option just output the diff that would be '
42                                   'introduced.')
43  parser.add_argument('-i', action='store_true', default=False,
44                      help='apply edits to files instead of displaying a diff')
45  parser.add_argument('-p', metavar='NUM', default=0,
46                      help='strip the smallest prefix containing P slashes')
47  parser.add_argument('-regex', metavar='PATTERN', default=None,
48                      help='custom pattern selecting file paths to reformat '
49                      '(case sensitive, overrides -iregex)')
50  parser.add_argument('-iregex', metavar='PATTERN', default=
51                      r'.*\.(cpp|cc|c\+\+|cxx|c|cl|h|hpp|m|mm|inc|js|ts|proto'
52                      r'|protodevel|java)',
53                      help='custom pattern selecting file paths to reformat '
54                      '(case insensitive, overridden by -regex)')
55  parser.add_argument('-sort-includes', action='store_true', default=False,
56                      help='let clang-format sort include blocks')
57  parser.add_argument('-v', '--verbose', action='store_true',
58                      help='be more verbose, ineffective without -i')
59  parser.add_argument('-style',
60                      help='formatting style to apply (LLVM, Google, Chromium, '
61                      'Mozilla, WebKit)')
62  parser.add_argument('-binary', default='clang-format',
63                      help='location of binary to use for clang-format')
64  args = parser.parse_args()
65
66  # Extract changed lines for each file.
67  filename = None
68  lines_by_file = {}
69  for line in sys.stdin:
70    match = re.search('^\+\+\+\ (.*?/){%s}(\S*)' % args.p, line)
71    if match:
72      filename = match.group(2)
73    if filename == None:
74      continue
75
76    if args.regex is not None:
77      if not re.match('^%s$' % args.regex, filename):
78        continue
79    else:
80      if not re.match('^%s$' % args.iregex, filename, re.IGNORECASE):
81        continue
82
83    match = re.search('^@@.*\+(\d+)(,(\d+))?', line)
84    if match:
85      start_line = int(match.group(1))
86      line_count = 1
87      if match.group(3):
88        line_count = int(match.group(3))
89      if line_count == 0:
90        continue
91      end_line = start_line + line_count - 1
92      lines_by_file.setdefault(filename, []).extend(
93          ['-lines', str(start_line) + ':' + str(end_line)])
94
95  # Reformat files containing changes in place.
96  for filename, lines in lines_by_file.items():
97    if args.i and args.verbose:
98      print('Formatting {}'.format(filename))
99    command = [args.binary, filename]
100    if args.i:
101      command.append('-i')
102    if args.sort_includes:
103      command.append('-sort-includes')
104    command.extend(lines)
105    if args.style:
106      command.extend(['-style', args.style])
107    p = subprocess.Popen(command,
108                         stdout=subprocess.PIPE,
109                         stderr=None,
110                         stdin=subprocess.PIPE,
111                         universal_newlines=True)
112    stdout, stderr = p.communicate()
113    if p.returncode != 0:
114      sys.exit(p.returncode)
115
116    if not args.i:
117      with open(filename) as f:
118        code = f.readlines()
119      formatted_code = StringIO(stdout).readlines()
120      diff = difflib.unified_diff(code, formatted_code,
121                                  filename, filename,
122                                  '(before formatting)', '(after formatting)')
123      diff_string = ''.join(diff)
124      if len(diff_string) > 0:
125        sys.stdout.write(diff_string)
126
127if __name__ == '__main__':
128  main()
129