#!/usr/bin/python

###
###  Copyright (C) 1998-2010 by the Free Software Foundation, Inc.
###
###  This program is free software; you can redistribute it and/or
###  modify it under the terms of the GNU General Public License
###  as published by the Free Software Foundation; either version 2
###  of the License, or (at your option) any later version.
###
###  This program is distributed in the hope that it will be useful,
###  but WITHOUT ANY WARRANTY; without even the implied warranty of
###  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
###  GNU General Public License for more details.
###
###  You should have received a copy of the GNU General Public License
###  along with this program; if not, write to the Free Software
###  Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
###  02110-1301, USA. http://www.fsf.org/licensing/licenses/gpl.html
###
###  ---------------------------
###
###  This object may be used to capture output that would have gone to
###  STDOUT (or STDERR).  It's based on the fact that (according to
###  Python docs), "stdout and stderr needn't be built-in file
###  objects: any object is acceptable as long as it has a write()
###  method that takes a string argument."
###
###  If you wanted to redirect sys.stdout to nothing, you could do:
###
###  class NullStream:
###      def write(self, text): pass
###  sys.stdout = NullStream()
###
###  But this class allows you to capture what would have otherwise
###  gone to STDOUT into a list, and then retrieve it later for
###  analysis.
###
###  This is useful when doing unit tests because it allows you to
###  capture what would have gone to STDOUT and check it for certain
###  things, without having stuff actually go to STDOUT and mess up
###  the unit test output.
###
###  It can be used like:
###
###  mylist = ListSream()
###  sys.stdout = mylist
###  test_method_that_prints()      # no output!
###  mylist.clear()                 # optional, only if plan to use again
###  sys.stdout = sys.__stdout__    # restore regular output
###  found = False
###  for line in mylist.contents():
###      if (re.search('looking_for', line)):
###          found = True
###          break
###  if (found): print 'looking_for was found in output!'
###
###  Author: Anthony R. Thompson
###  Contact: put @ between art and sigilservices.com
###  Created: Nov 2009
###

class ListStream:
    def __init__(self): self.mysavelist = []
    def write(self, text): self.mysavelist.append(text)
    def clear(self): self.mysavelist = []
    def contents(self): return self.mysavelist
    def readlines(self): return self.mysavelist

if __name__ == '__main__':
    pass