xref: /llvm-project/clang/tools/clang-format/clang-format.py (revision ffaf29a07b0722e436fc37e1659504f03a34413c) 
1# This file is a minimal clang-format vim-integration. To install:
2# - Change 'binary' if clang-format is not on the path (see below).
3# - Add to your .vimrc:
4#
5#   map <C-I> :pyf <path-to-this-file>/clang-format.py<CR>
6#   imap <C-I> <ESC>:pyf <path-to-this-file>/clang-format.py<CR>i
7#
8# The first line enables clang-format for NORMAL and VISUAL mode, the second
9# line adds support for INSERT mode. Change "C-I" to another binding if you
10# need clang-format on a different key (C-I stands for Ctrl+i).
11#
12# With this integration you can press the bound key and clang-format will
13# format the current line in NORMAL and INSERT mode or the selected region in
14# VISUAL mode. The line or region is extended to the next bigger syntactic
15# entity.
16#
17# It operates on the current, potentially unsaved buffer and does not create
18# or save any files. To revert a formatting, just undo.
19
20import difflib
21import json
22import subprocess
23import sys
24import vim
25
26# Change this to the full path if clang-format is not on the path.
27binary = 'clang-format'
28
29# Change this to format according to other formatting styles. See the output of
30# 'clang-format --help' for a list of supported styles. The default looks for
31# a '.clang-format' or '_clang-format' file to indicate the style that should be
32# used.
33style = 'file'
34
35def main():
36  # Get the current text.
37  buf = vim.current.buffer
38  text = '\n'.join(buf)
39
40  # Determine range to format.
41  cursor = int(vim.eval('line2byte(line("."))+col(".")')) - 2
42  lines = '%s:%s' % (vim.current.range.start + 1, vim.current.range.end + 1)
43
44  # Avoid flashing an ugly, ugly cmd prompt on Windows when invoking clang-format.
45  startupinfo = None
46  if sys.platform.startswith('win32'):
47    startupinfo = subprocess.STARTUPINFO()
48    startupinfo.dwFlags |= subprocess.STARTF_USESHOWWINDOW
49    startupinfo.wShowWindow = subprocess.SW_HIDE
50
51  # Call formatter.
52  command = [binary, '-lines', lines, '-style', style, '-cursor', str(cursor)]
53  if vim.current.buffer.name:
54    command.extend(['-assume-filename', vim.current.buffer.name])
55  p = subprocess.Popen(command,
56                       stdout=subprocess.PIPE, stderr=subprocess.PIPE,
57                       stdin=subprocess.PIPE, startupinfo=startupinfo)
58  stdout, stderr = p.communicate(input=text)
59
60  # If successful, replace buffer contents.
61  if stderr:
62    print stderr
63
64  if not stdout:
65    print ('No output from clang-format (crashed?).\n' +
66        'Please report to bugs.llvm.org.')
67  else:
68    lines = stdout.split('\n')
69    output = json.loads(lines[0])
70    lines = lines[1:]
71    sequence = difflib.SequenceMatcher(None, vim.current.buffer, lines)
72    for op in reversed(sequence.get_opcodes()):
73      if op[0] is not 'equal':
74        vim.current.buffer[op[1]:op[2]] = lines[op[3]:op[4]]
75    vim.command('goto %d' % (output['Cursor'] + 1))
76
77main()
78