tools/sort-headers.py

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