Tools/scripts/methfix.py

   1 #! /usr/bin/env python
   2
   3 # Fix Python source files to avoid using
   4 #       def method(self, (arg1, ..., argn)):
   5 # instead of the more rational
   6 #       def method(self, arg1, ..., argn):
   7 #
   8 # Command line arguments are files or directories to be processed.
   9 # Directories are searched recursively for files whose name looks
  10 # like a python module.
  11 # Symbolic links are always ignored (except as explicit directory
  12 # arguments).  Of course, the original file is kept as a back-up
  13 # (with a "~" attached to its name).
  14 # It complains about binaries (files containing null bytes)
  15 # and about files that are ostensibly not Python files: if the first
  16 # line starts with '#!' and does not contain the string 'python'.
  17 #
  18 # Changes made are reported to stdout in a diff-like format.
  19 #
  20 # Undoubtedly you can do this using find and sed or perl, but this is
  21 # a nice example of Python code that recurses down a directory tree
  22 # and uses regular expressions.  Also note several subtleties like
  23 # preserving the file's mode and avoiding to even write a temp file
  24 # when no changes are needed for a file.
  25 #
  26 # NB: by changing only the function fixline() you can turn this
  27 # into a program for a different change to Python programs...
  28
  29 import sys
  30 import regex
  31 import os
  32 from stat import *
  33 import string
  34
  35 err = sys.stderr.write
  36 dbg = err
  37 rep = sys.stdout.write
  38
  39 def main():
  40         bad = 0
  41         if not sys.argv[1:]: # No arguments
  42                 err('usage: ' + sys.argv[0] + ' file-or-directory ...\n')
  43                 sys.exit(2)
  44         for arg in sys.argv[1:]:
  45                 if os.path.isdir(arg):
  46                         if recursedown(arg): bad = 1
  47                 elif os.path.islink(arg):
  48                         err(arg + ': will not process symbolic links\n')
  49                         bad = 1
  50                 else:
  51                         if fix(arg): bad = 1
  52         sys.exit(bad)
  53
  54 ispythonprog = regex.compile('^[a-zA-Z0-9_]+\.py$')
  55 def ispython(name):
  56         return ispythonprog.match(name) >= 0
  57
  58 def recursedown(dirname):
  59         dbg('recursedown(' + `dirname` + ')\n')
  60         bad = 0
  61         try:
  62                 names = os.listdir(dirname)
  63         except os.error, msg:
  64                 err(dirname + ': cannot list directory: ' + `msg` + '\n')
  65                 return 1
  66         names.sort()
  67         subdirs = []
  68         for name in names:
  69                 if name in (os.curdir, os.pardir): continue
  70                 fullname = os.path.join(dirname, name)
  71                 if os.path.islink(fullname): pass
  72                 elif os.path.isdir(fullname):
  73                         subdirs.append(fullname)
  74                 elif ispython(name):
  75                         if fix(fullname): bad = 1
  76         for fullname in subdirs:
  77                 if recursedown(fullname): bad = 1
  78         return bad
  79
  80 def fix(filename):
  81 ##      dbg('fix(' + `filename` + ')\n')
  82         try:
  83                 f = open(filename, 'r')
  84         except IOError, msg:
  85                 err(filename + ': cannot open: ' + `msg` + '\n')
  86                 return 1
  87         head, tail = os.path.split(filename)
  88         tempname = os.path.join(head, '@' + tail)
  89         g = None
  90         # If we find a match, we rewind the file and start over but
  91         # now copy everything to a temp file.
  92         lineno = 0
  93         while 1:
  94                 line = f.readline()
  95                 if not line: break
  96                 lineno = lineno + 1
  97                 if g is None and '\0' in line:
  98                         # Check for binary files
  99                         err(filename + ': contains null bytes; not fixed\n')
 100                         f.close()
 101                         return 1
 102                 if lineno == 1 and g is None and line[:2] == '#!':
 103                         # Check for non-Python scripts
 104                         words = string.split(line[2:])
 105                         if words and regex.search('[pP]ython', words[0]) < 0:
 106                                 msg = filename + ': ' + words[0]
 107                                 msg = msg + ' script; not fixed\n'
 108                                 err(msg)
 109                                 f.close()
 110                                 return 1
 111                 while line[-2:] == '\\\n':
 112                         nextline = f.readline()
 113                         if not nextline: break
 114                         line = line + nextline
 115                         lineno = lineno + 1
 116                 newline = fixline(line)
 117                 if newline != line:
 118                         if g is None:
 119                                 try:
 120                                         g = open(tempname, 'w')
 121                                 except IOError, msg:
 122                                         f.close()
 123                                         err(tempname+': cannot create: '+\
 124                                             `msg`+'\n')
 125                                         return 1
 126                                 f.seek(0)
 127                                 lineno = 0
 128                                 rep(filename + ':\n')
 129                                 continue # restart from the beginning
 130                         rep(`lineno` + '\n')
 131                         rep('< ' + line)
 132                         rep('> ' + newline)
 133                 if g is not None:
 134                         g.write(newline)
 135
 136         # End of file
 137         f.close()
 138         if not g: return 0 # No changes
 139
 140         # Finishing touch -- move files
 141
 142         # First copy the file's mode to the temp file
 143         try:
 144                 statbuf = os.stat(filename)
 145                 os.chmod(tempname, statbuf[ST_MODE] & 07777)
 146         except os.error, msg:
 147                 err(tempname + ': warning: chmod failed (' + `msg` + ')\n')
 148         # Then make a backup of the original file as filename~
 149         try:
 150                 os.rename(filename, filename + '~')
 151         except os.error, msg:
 152                 err(filename + ': warning: backup failed (' + `msg` + ')\n')
 153         # Now move the temp file to the original file
 154         try:
 155                 os.rename(tempname, filename)
 156         except os.error, msg:
 157                 err(filename + ': rename failed (' + `msg` + ')\n')
 158                 return 1
 159         # Return succes
 160         return 0
 161
 162
 163 fixpat = '^[ \t]+def +[a-zA-Z0-9_]+ *( *self *, *\(( *\(.*\) *)\) *) *:'
 164 fixprog = regex.compile(fixpat)
 165
 166 def fixline(line):
 167         if fixprog.match(line) >= 0:
 168                 (a, b), (c, d) = fixprog.regs[1:3]
 169                 line = line[:a] + line[c:d] + line[b:]
 170         return line
 171
 172
 173 main()