1# Copyright (c) 2009, Google Inc. All rights reserved. 2# 3# Redistribution and use in source and binary forms, with or without 4# modification, are permitted provided that the following conditions are 5# met: 6# 7# * Redistributions of source code must retain the above copyright 8# notice, this list of conditions and the following disclaimer. 9# * Redistributions in binary form must reproduce the above 10# copyright notice, this list of conditions and the following disclaimer 11# in the documentation and/or other materials provided with the 12# distribution. 13# * Neither the name of Google Inc. nor the names of its 14# contributors may be used to endorse or promote products derived from 15# this software without specific prior written permission. 16# 17# THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 18# "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 19# LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 20# A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 21# OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 22# SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 23# LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 24# DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 25# THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 26# (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 27# OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 28# 29# Class for unittest support. Used for capturing stderr/stdout. 30 31import sys 32from StringIO import StringIO 33 34class OutputCapture(object): 35 def __init__(self): 36 self.saved_outputs = dict() 37 38 def _capture_output_with_name(self, output_name): 39 self.saved_outputs[output_name] = getattr(sys, output_name) 40 setattr(sys, output_name, StringIO()) 41 42 def _restore_output_with_name(self, output_name): 43 captured_output = getattr(sys, output_name).getvalue() 44 setattr(sys, output_name, self.saved_outputs[output_name]) 45 del self.saved_outputs[output_name] 46 return captured_output 47 48 def capture_output(self): 49 self._capture_output_with_name("stdout") 50 self._capture_output_with_name("stderr") 51 52 def restore_output(self): 53 return (self._restore_output_with_name("stdout"), self._restore_output_with_name("stderr")) 54 55 def assert_outputs(self, testcase, function, args=[], kwargs={}, expected_stdout="", expected_stderr=""): 56 self.capture_output() 57 return_value = function(*args, **kwargs) 58 (stdout_string, stderr_string) = self.restore_output() 59 testcase.assertEqual(stdout_string, expected_stdout) 60 testcase.assertEqual(stderr_string, expected_stderr) 61 # This is a little strange, but I don't know where else to return this information. 62 return return_value 63