tools/sort-headers.py

   1 #!/usr/bin/python
   2 # Copyright (c) 2011 The Chromium Authors. All rights reserved.
   3 # Use of this source code is governed by a BSD-style license that can be
   4 # found in the LICENSE file.
   5
   6 """Given a filename as an argument, sort the #include/#imports in that file.
   7
   8 Shows a diff and prompts for confirmation before doing the deed.
   9 """
  10
  11 import optparse
  12 import os
  13 import sys
  14 import termios
  15 import tty
  16
  17 def YesNo(prompt):
  18   """Prompts with a yes/no question, returns True if yes."""
  19   print prompt,
  20   sys.stdout.flush()
  21   # http://code.activestate.com/recipes/134892/
  22   fd = sys.stdin.fileno()
  23   old_settings = termios.tcgetattr(fd)
  24   ch = 'n'
  25   try:
  26     tty.setraw(sys.stdin.fileno())
  27     ch = sys.stdin.read(1)
  28   finally:
  29     termios.tcsetattr(fd, termios.TCSADRAIN, old_settings)
  30   print ch
  31   return ch in ('Y', 'y')
  32
  33
  34 def IncludeCompareKey(line):
  35   """Sorting comparator key used for comparing two #include lines.
  36   Returns the filename without the #include/#import prefix.
  37   """
  38   for prefix in ('#include ', '#import '):
  39     if line.startswith(prefix):
  40       line = line[len(prefix):]
  41       break
  42
  43   # The win32 api has all sorts of implicit include order dependencies :-/
  44   # Give a few headers special sort keys that make sure they appear before all
  45   # other headers.
  46   if line.startswith('<windows.h>'):  # Must be before e.g. shellapi.h
  47     return '0'
  48   if line.startswith('<unknwn.h>'):  # Must be before e.g. intshcut.h
  49     return '1'
  50
  51   return line
  52
  53
  54 def IsInclude(line):
  55   """Returns True if the line is an #include/#import line."""
  56   return line.startswith('#include ') or line.startswith('#import ')
  57
  58
  59 def SortHeader(infile, outfile):
  60   """Sorts the headers in infile, writing the sorted file to outfile."""
  61   for line in infile:
  62     if IsInclude(line):
  63       headerblock = []
  64       while IsInclude(line):
  65         headerblock.append(line)
  66         line = infile.next()
  67       for header in sorted(headerblock, key=IncludeCompareKey):
  68         outfile.write(header)
  69       # Intentionally fall through, to write the line that caused
  70       # the above while loop to exit.
  71     outfile.write(line)
  72
  73
  74 def main():
  75   parser = optparse.OptionParser(usage='%prog filename1 filename2 ...')
  76   opts, args = parser.parse_args()
  77
  78   if len(args) < 1:
  79     parser.print_help()
  80     sys.exit(1)
  81
  82   for filename in args:
  83     fixfilename = filename + '.new'
  84     infile = open(filename, 'r')
  85     outfile = open(fixfilename, 'w')
  86     SortHeader(infile, outfile)
  87     infile.close()
  88     outfile.close()  # Important so the below diff gets the updated contents.
  89
  90     try:
  91       diff = os.system('diff -u %s %s' % (filename, fixfilename))
  92       if diff >> 8 == 0:  # Check exit code.
  93         print '%s: no change' % filename
  94         continue
  95
  96       if YesNo('Use new file (y/N)?'):
  97         os.rename(fixfilename, filename)
  98     finally:
  99       try:
 100         os.remove(fixfilename)
 101       except OSError:
 102         # If the file isn't there, we don't care.
 103         pass
 104
 105
 106 if __name__ == '__main__':
 107   main()