/Demo/scripts/update.py
http://unladen-swallow.googlecode.com/ · Python · 92 lines · 78 code · 8 blank · 6 comment · 22 complexity · 2e0371f5730d92ac4d3812dc112e504e MD5 · raw file
- #! /usr/bin/env python
- # Update a bunch of files according to a script.
- # The input file contains lines of the form <filename>:<lineno>:<text>,
- # meaning that the given line of the given file is to be replaced
- # by the given text. This is useful for performing global substitutions
- # on grep output:
- import os
- import sys
- import re
- pat = '^([^: \t\n]+):([1-9][0-9]*):'
- prog = re.compile(pat)
- class FileObj:
- def __init__(self, filename):
- self.filename = filename
- self.changed = 0
- try:
- self.lines = open(filename, 'r').readlines()
- except IOError, msg:
- print '*** Can\'t open "%s":' % filename, msg
- self.lines = None
- return
- print 'diffing', self.filename
- def finish(self):
- if not self.changed:
- print 'no changes to', self.filename
- return
- try:
- os.rename(self.filename, self.filename + '~')
- fp = open(self.filename, 'w')
- except (os.error, IOError), msg:
- print '*** Can\'t rewrite "%s":' % self.filename, msg
- return
- print 'writing', self.filename
- for line in self.lines:
- fp.write(line)
- fp.close()
- self.changed = 0
- def process(self, lineno, rest):
- if self.lines is None:
- print '(not processed): %s:%s:%s' % (
- self.filename, lineno, rest),
- return
- i = eval(lineno) - 1
- if not 0 <= i < len(self.lines):
- print '*** Line number out of range: %s:%s:%s' % (
- self.filename, lineno, rest),
- return
- if self.lines[i] == rest:
- print '(no change): %s:%s:%s' % (
- self.filename, lineno, rest),
- return
- if not self.changed:
- self.changed = 1
- print '%sc%s' % (lineno, lineno)
- print '<', self.lines[i],
- print '---'
- self.lines[i] = rest
- print '>', self.lines[i],
- def main():
- if sys.argv[1:]:
- try:
- fp = open(sys.argv[1], 'r')
- except IOError, msg:
- print 'Can\'t open "%s":' % sys.argv[1], msg
- sys.exit(1)
- else:
- fp = sys.stdin
- curfile = None
- while 1:
- line = fp.readline()
- if not line:
- if curfile: curfile.finish()
- break
- n = prog.match(line)
- if n < 0:
- print 'Funny line:', line,
- continue
- filename, lineno = prog.group(1, 2)
- if not curfile or filename <> curfile.filename:
- if curfile: curfile.finish()
- curfile = FileObj(filename)
- curfile.process(lineno, line[n:])
- if __name__ == "__main__":
- main()