1#!/usr/bin/env python3 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 --relative HEAD^ | {clang_format_diff} -p1 -i 17 svn diff --diff-cmd=diff -x-U0 | {clang_format_diff} -i 18 19It should be noted that the filename contained in the diff is used unmodified 20to determine the source file to update. Users calling this script directly 21should be careful to ensure that the path in the diff is correct relative to the 22current working directory. 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( 40 description=__doc__.format(clang_format_diff="%(prog)s"), 41 formatter_class=argparse.RawDescriptionHelpFormatter, 42 ) 43 parser.add_argument( 44 "-i", 45 action="store_true", 46 default=False, 47 help="apply edits to files instead of displaying a diff", 48 ) 49 parser.add_argument( 50 "-p", 51 metavar="NUM", 52 default=0, 53 help="strip the smallest prefix containing P slashes", 54 ) 55 parser.add_argument( 56 "-regex", 57 metavar="PATTERN", 58 default=None, 59 help="custom pattern selecting file paths to reformat " 60 "(case sensitive, overrides -iregex)", 61 ) 62 parser.add_argument( 63 "-iregex", 64 metavar="PATTERN", 65 default=r".*\.(?:cpp|cc|c\+\+|cxx|cppm|ccm|cxxm|c\+\+m|c|cl|h|hh|hpp" 66 r"|hxx|m|mm|inc|js|ts|proto|protodevel|java|cs|json|s?vh?)", 67 help="custom pattern selecting file paths to reformat " 68 "(case insensitive, overridden by -regex)", 69 ) 70 parser.add_argument( 71 "-sort-includes", 72 action="store_true", 73 default=False, 74 help="let clang-format sort include blocks", 75 ) 76 parser.add_argument( 77 "-v", 78 "--verbose", 79 action="store_true", 80 help="be more verbose, ineffective without -i", 81 ) 82 parser.add_argument( 83 "-style", 84 help="formatting style to apply (LLVM, GNU, Google, Chromium, " 85 "Microsoft, Mozilla, WebKit)", 86 ) 87 parser.add_argument( 88 "-fallback-style", 89 help="The name of the predefined style used as a" 90 "fallback in case clang-format is invoked with" 91 "-style=file, but can not find the .clang-format" 92 "file to use.", 93 ) 94 parser.add_argument( 95 "-binary", 96 default="clang-format", 97 help="location of binary to use for clang-format", 98 ) 99 args = parser.parse_args() 100 101 # Extract changed lines for each file. 102 filename = None 103 lines_by_file = {} 104 for line in sys.stdin: 105 match = re.search(r"^\+\+\+\ (.*?/){%s}(\S*)" % args.p, line) 106 if match: 107 filename = match.group(2) 108 if filename is None: 109 continue 110 111 if args.regex is not None: 112 if not re.match("^%s$" % args.regex, filename): 113 continue 114 else: 115 if not re.match("^%s$" % args.iregex, filename, re.IGNORECASE): 116 continue 117 118 match = re.search(r"^@@.*\+(\d+)(?:,(\d+))?", line) 119 if match: 120 start_line = int(match.group(1)) 121 line_count = 1 122 if match.group(2): 123 line_count = int(match.group(2)) 124 # The input is something like 125 # 126 # @@ -1, +0,0 @@ 127 # 128 # which means no lines were added. 129 if line_count == 0: 130 continue 131 # Also format lines range if line_count is 0 in case of deleting 132 # surrounding statements. 133 end_line = start_line 134 if line_count != 0: 135 end_line += line_count - 1 136 lines_by_file.setdefault(filename, []).extend( 137 ["--lines", str(start_line) + ":" + str(end_line)] 138 ) 139 140 # Reformat files containing changes in place. 141 has_diff = False 142 for filename, lines in lines_by_file.items(): 143 if args.i and args.verbose: 144 print("Formatting {}".format(filename)) 145 command = [args.binary, filename] 146 if args.i: 147 command.append("-i") 148 if args.sort_includes: 149 command.append("--sort-includes") 150 command.extend(lines) 151 if args.style: 152 command.extend(["--style", args.style]) 153 if args.fallback_style: 154 command.extend(["--fallback-style", args.fallback_style]) 155 156 try: 157 p = subprocess.Popen( 158 command, 159 stdout=subprocess.PIPE, 160 stderr=None, 161 stdin=subprocess.PIPE, 162 universal_newlines=True, 163 ) 164 except OSError as e: 165 # Give the user more context when clang-format isn't 166 # found/isn't executable, etc. 167 raise RuntimeError( 168 'Failed to run "%s" - %s"' % (" ".join(command), e.strerror) 169 ) 170 171 stdout, _stderr = p.communicate() 172 if p.returncode != 0: 173 return p.returncode 174 175 if not args.i: 176 with open(filename) as f: 177 code = f.readlines() 178 formatted_code = StringIO(stdout).readlines() 179 diff = difflib.unified_diff( 180 code, 181 formatted_code, 182 filename, 183 filename, 184 "(before formatting)", 185 "(after formatting)", 186 ) 187 diff_string = "".join(diff) 188 if len(diff_string) > 0: 189 has_diff = True 190 sys.stdout.write(diff_string) 191 192 if has_diff: 193 return 1 194 195 196if __name__ == "__main__": 197 sys.exit(main()) 198