code.vuplus.com Git - vuplus_webkit/blob - Tools/Scripts/webkitpy/common/system/outputcapture.py

   1 # Copyright (c) 2009, Google Inc. All rights reserved.
   2 #
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   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.
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  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
  31 import sys
  32 import unittest
  33 from StringIO import StringIO
  34
  35
  36 class OutputCapture(object):
  37     def __init__(self):
  38         self.saved_outputs = dict()
  39
  40     def _capture_output_with_name(self, output_name):
  41         self.saved_outputs[output_name] = getattr(sys, output_name)
  42         captured_output = StringIO()
  43         setattr(sys, output_name, captured_output)
  44         return captured_output
  45
  46     def _restore_output_with_name(self, output_name):
  47         captured_output = getattr(sys, output_name).getvalue()
  48         setattr(sys, output_name, self.saved_outputs[output_name])
  49         del self.saved_outputs[output_name]
  50         return captured_output
  51
  52     def capture_output(self):
  53         return (self._capture_output_with_name("stdout"), self._capture_output_with_name("stderr"))
  54
  55     def restore_output(self):
  56         return (self._restore_output_with_name("stdout"), self._restore_output_with_name("stderr"))
  57
  58     def assert_outputs(self, testcase, function, args=[], kwargs={}, expected_stdout="", expected_stderr="", expected_exception=None):
  59         self.capture_output()
  60         if expected_exception:
  61             return_value = testcase.assertRaises(expected_exception, function, *args, **kwargs)
  62         else:
  63             return_value = function(*args, **kwargs)
  64         (stdout_string, stderr_string) = self.restore_output()
  65         testcase.assertEqual(stdout_string, expected_stdout)
  66         testcase.assertEqual(stderr_string, expected_stderr)
  67         # This is a little strange, but I don't know where else to return this information.
  68         return return_value
  69
  70
  71 class OutputCaptureTestCaseBase(unittest.TestCase):
  72     def setUp(self):
  73         unittest.TestCase.setUp(self)
  74         self.output_capture = OutputCapture()
  75         (self.__captured_stdout, self.__captured_stderr) = self.output_capture.capture_output()
  76
  77     def tearDown(self):
  78         del self.__captured_stdout
  79         del self.__captured_stderr
  80         self.output_capture.restore_output()
  81         unittest.TestCase.tearDown(self)
  82
  83     def assertStdout(self, expected_stdout):
  84         self.assertEquals(expected_stdout, self.__captured_stdout.getvalue())
  85
  86     def assertStderr(self, expected_stderr):
  87         self.assertEquals(expected_stderr, self.__captured_stderr.getvalue())