#! /usr/bin/env python # This script is obsolete -- it is kept for historical purposes only.## Fix Python source files to use the new class definition syntax, i.e.,# the syntax used in Python versions before 0.9.8:#       class C() = base(), base(), ...: ...# is changed to the current syntax:#       class C(base, base, ...): ...## The script uses heuristics to find class definitions that usually# work but occasionally can fail; carefully check the output!## Command line arguments are files or directories to be processed.# Directories are searched recursively for files whose name looks# like a python module.# Symbolic links are always ignored (except as explicit directory# arguments).  Of course, the original file is kept as a back-up# (with a "~" attached to its name).## Changes made are reported to stdout in a diff-like format.## Undoubtedly you can do this using find and sed or perl, but this is# a nice example of Python code that recurses down a directory tree# and uses regular expressions.  Also note several subtleties like# preserving the file's mode and avoiding to even write a temp file# when no changes are needed for a file.## NB: by changing only the function fixline() you can turn this# into a program for a different change to Python programs... import sysimport reimport osfrom stat import * err = sys.stderr.writedbg = errrep = sys.stdout.write def main():    bad = 0    if not sys.argv[1:]: # No arguments        err('usage: ' + sys.argv[0] + ' file-or-directory ...\n')        sys.exit(2)    for arg in sys.argv[1:]:        if os.path.isdir(arg):            if recursedown(arg): bad = 1        elif os.path.islink(arg):            err(arg + ': will not process symbolic links\n')            bad = 1        else:            if fix(arg): bad = 1    sys.exit(bad) ispythonprog = re.compile('^[a-zA-Z0-9_]+\.py$')def ispython(name):    return ispythonprog.match(name) >= 0 def recursedown(dirname):    dbg('recursedown(%r)\n' % (dirname,))    bad = 0    try:        names = os.listdir(dirname)    except os.error, msg:        err('%s: cannot list directory: %r\n' % (dirname, msg))        return 1    names.sort()    subdirs = []    for name in names:        if name in (os.curdir, os.pardir): continue        fullname = os.path.join(dirname, name)        if os.path.islink(fullname): pass        elif os.path.isdir(fullname):            subdirs.append(fullname)        elif ispython(name):            if fix(fullname): bad = 1    for fullname in subdirs:        if recursedown(fullname): bad = 1    return bad def fix(filename):##  dbg('fix(%r)\n' % (filename,))    try:        f = open(filename, 'r')    except IOError, msg:        err('%s: cannot open: %r\n' % (filename, msg))        return 1    head, tail = os.path.split(filename)    tempname = os.path.join(head, '@' + tail)    g = None    # If we find a match, we rewind the file and start over but    # now copy everything to a temp file.    lineno = 0    while 1:        line = f.readline()        if not line: break        lineno = lineno + 1        while line[-2:] == '\\\n':            nextline = f.readline()            if not nextline: break            line = line + nextline            lineno = lineno + 1        newline = fixline(line)        if newline != line:            if g is None:                try:                    g = open(tempname, 'w')                except IOError, msg:                    f.close()                    err('%s: cannot create: %r\n' % (tempname, msg))                    return 1                f.seek(0)                lineno = 0                rep(filename + ':\n')                continue # restart from the beginning            rep(repr(lineno) + '\n')            rep('< ' + line)            rep('> ' + newline)        if g is not None:            g.write(newline)     # End of file    f.close()    if not g: return 0 # No changes     # Finishing touch -- move files     # First copy the file's mode to the temp file    try:        statbuf = os.stat(filename)        os.chmod(tempname, statbuf[ST_MODE] & 07777)    except os.error, msg:        err('%s: warning: chmod failed (%r)\n' % (tempname, msg))    # Then make a backup of the original file as filename~    try:        os.rename(filename, filename + '~')    except os.error, msg:        err('%s: warning: backup failed (%r)\n' % (filename, msg))    # Now move the temp file to the original file    try:        os.rename(tempname, filename)    except os.error, msg:        err('%s: rename failed (%r)\n' % (filename, msg))        return 1    # Return succes    return 0 # This expression doesn't catch *all* class definition headers,# but it's pretty darn close.classexpr = '^([ \t]*class +[a-zA-Z0-9_]+) *( *) *((=.*)?):'classprog = re.compile(classexpr) # Expressions for finding base class expressions.baseexpr = '^ *(.*) *( *) *$'baseprog = re.compile(baseexpr) def fixline(line):    if classprog.match(line) < 0: # No 'class' keyword -- no change        return line     (a0, b0), (a1, b1), (a2, b2) = classprog.regs[:3]    # a0, b0 = Whole match (up to ':')    # a1, b1 = First subexpression (up to classname)    # a2, b2 = Second subexpression (=.*)    head = line[:b1]    tail = line[b0:] # Unmatched rest of line     if a2 == b2: # No base classes -- easy case        return head + ':' + tail     # Get rid of leading '='    basepart = line[a2+1:b2]     # Extract list of base expressions    bases = basepart.split(',')     # Strip trailing '()' from each base expression    for i in range(len(bases)):        if baseprog.match(bases[i]) >= 0:            x1, y1 = baseprog.regs[1]            bases[i] = bases[i][x1:y1]     # Join the bases back again and build the new line    basepart = ', '.join(bases)     return head + '(' + basepart + '):' + tail if __name__ == '__main__':    main()