ninjasort.py

#!/usr/bin/env python

import os
import re
import sys


def main():
  for root, _, files in os.walk(sys.argv[1]):
    for file_name in files:
      if file_name.endswith('.ninja'):
        sortFile(os.path.join(root, file_name))


def sortFile(path):
  lines = open(path).readlines()
  targets = {}
  out = ''
  for line in lines:
    if not line.startswith('build '):
      out += line
      continue
    (cmd, deps) = line.split(':', 1)
    cmd_deps = ''
    for dep in sorted(deps.split()):
      cmd_deps += '  ' + dep + '\n'
    targets[cmd] = cmd_deps
  for (cmd, deps) in sorted(targets.iteritems()):
    out += cmd + ':\n' + deps + '\n'

  with open(path + '.new', 'w') as ofile:
    ofile.write(out)
  os.rename(path + '.new', path)

if __name__ == '__main__':
  main()