Inside Bitcoin

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
32from io import StringIO
33
34
35def main():
36    parser = argparse.ArgumentParser(
37        description=__doc__.format(clang_format_diff="%(prog)s"),
38        formatter_class=argparse.RawDescriptionHelpFormatter,
39    )
40    parser.add_argument(
41        "-i",
42        action="store_true",
43        default=False,
44        help="apply edits to files instead of displaying a diff",
45    )
46    parser.add_argument(
47        "-p",
48        metavar="NUM",
49        default=0,
50        help="strip the smallest prefix containing P slashes",
51    )
52    parser.add_argument(
53        "-regex",
54        metavar="PATTERN",
55        default=None,
56        help="custom pattern selecting file paths to reformat "
57        "(case sensitive, overrides -iregex)",
58    )
59    parser.add_argument(
60        "-iregex",
61        metavar="PATTERN",
62        default=r".*\.(?:cpp|cc|c\+\+|cxx|cppm|ccm|cxxm|c\+\+m|c|cl|h|hh|hpp"
63        r"|hxx|m|mm|inc|js|ts|proto|protodevel|java|cs|json|s?vh?)",
64        help="custom pattern selecting file paths to reformat "
65        "(case insensitive, overridden by -regex)",
66    )
67    parser.add_argument(
68        "-sort-includes",
69        action="store_true",
70        default=False,
71        help="let clang-format sort include blocks",
72    )
73    parser.add_argument(
74        "-v",
75        "--verbose",
76        action="store_true",
77        help="be more verbose, ineffective without -i",
78    )
79    parser.add_argument(
80        "-style",
81        help="formatting style to apply (LLVM, GNU, Google, Chromium, "
82        "Microsoft, Mozilla, WebKit)",
83    )
84    parser.add_argument(
85        "-fallback-style",
86        help="The name of the predefined style used as a"
87        "fallback in case clang-format is invoked with"
88        "-style=file, but can not find the .clang-format"
89        "file to use.",
90    )
91    parser.add_argument(
92        "-binary",
93        default="clang-format",
94        help="location of binary to use for clang-format",
95    )
96    args = parser.parse_args()
97
98    # Extract changed lines for each file.
99    filename = None
100    lines_by_file = {}
101    for line in sys.stdin:
102        match = re.search(r"^\+\+\+\ (.*?/){%s}(\S*)" % args.p, line)
103        if match:
104            filename = match.group(2)
105        if filename is None:
106            continue
107
108        if args.regex is not None:
109            if not re.match("^%s$" % args.regex, filename):
110                continue
111        else:
112            if not re.match("^%s$" % args.iregex, filename, re.IGNORECASE):
113                continue
114
115        match = re.search(r"^@@.*\+(\d+)(?:,(\d+))?", line)
116        if match:
117            start_line = int(match.group(1))
118            line_count = 1
119            if match.group(2):
120                line_count = int(match.group(2))
121                # The input is something like
122                #
123                # @@ -1, +0,0 @@
124                #
125                # which means no lines were added.
126                if line_count == 0:
127                    continue
128            # Also format lines range if line_count is 0 in case of deleting
129            # surrounding statements.
130            end_line = start_line
131            if line_count != 0:
132                end_line += line_count - 1
133            lines_by_file.setdefault(filename, []).extend(
134                ["-lines", str(start_line) + ":" + str(end_line)]
135            )
136
137    # Reformat files containing changes in place.
138    for filename, lines in lines_by_file.items():
139        if args.i and args.verbose:
140            print("Formatting {}".format(filename))
141        command = [args.binary, filename]
142        if args.i:
143            command.append("-i")
144        if args.sort_includes:
145            command.append("-sort-includes")
146        command.extend(lines)
147        if args.style:
148            command.extend(["-style", args.style])
149        if args.fallback_style:
150            command.extend(["-fallback-style", args.fallback_style])
151
152        try:
153            p = subprocess.Popen(
154                command,
155                stdout=subprocess.PIPE,
156                stderr=None,
157                stdin=subprocess.PIPE,
158                universal_newlines=True,
159            )
160        except OSError as e:
161            # Give the user more context when clang-format isn't
162            # found/isn't executable, etc.
163            raise RuntimeError(
164                'Failed to run "%s" - %s"' % (" ".join(command), e.strerror)
165            )
166
167        stdout, _stderr = p.communicate()
168        if p.returncode != 0:
169            sys.exit(p.returncode)
170
171        if not args.i:
172            with open(filename) as f:
173                code = f.readlines()
174            formatted_code = StringIO(stdout).readlines()
175            diff = difflib.unified_diff(
176                code,
177                formatted_code,
178                filename,
179                filename,
180                "(before formatting)",
181                "(after formatting)",
182            )
183            diff_string = "".join(diff)
184            if len(diff_string) > 0:
185                sys.stdout.write(diff_string)
186                sys.exit(1)
187
188
189if __name__ == "__main__":
190    main()
191