Clean up ChunkedUpdateDrawingAreaProxy
[WebKit-https.git] / Tools / Scripts / webkitpy / common / system / outputcapture.py
1 # Copyright (c) 2009, Google Inc. All rights reserved.
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6
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15 # this software without specific prior written permission.
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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,
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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 class OutputCapture(object):
36     def __init__(self):
37         self.saved_outputs = dict()
38
39     def _capture_output_with_name(self, output_name):
40         self.saved_outputs[output_name] = getattr(sys, output_name)
41         captured_output = StringIO()
42         setattr(sys, output_name, captured_output)
43         return captured_output
44
45     def _restore_output_with_name(self, output_name):
46         captured_output = getattr(sys, output_name).getvalue()
47         setattr(sys, output_name, self.saved_outputs[output_name])
48         del self.saved_outputs[output_name]
49         return captured_output
50
51     def capture_output(self):
52         return (self._capture_output_with_name("stdout"), self._capture_output_with_name("stderr"))
53
54     def restore_output(self):
55         return (self._restore_output_with_name("stdout"), self._restore_output_with_name("stderr"))
56
57     def assert_outputs(self, testcase, function, args=[], kwargs={}, expected_stdout="", expected_stderr="", expected_exception=None):
58         self.capture_output()
59         if expected_exception:
60             return_value = testcase.assertRaises(expected_exception, function, *args, **kwargs)
61         else:
62             return_value = function(*args, **kwargs)
63         (stdout_string, stderr_string) = self.restore_output()
64         testcase.assertEqual(stdout_string, expected_stdout)
65         testcase.assertEqual(stderr_string, expected_stderr)
66         # This is a little strange, but I don't know where else to return this information.
67         return return_value
68
69
70 class OutputCaptureTestCaseBase(unittest.TestCase):
71     def setUp(self):
72         unittest.TestCase.setUp(self)
73         self.output_capture = OutputCapture()
74         (self.__captured_stdout, self.__captured_stderr) = self.output_capture.capture_output()
75
76     def tearDown(self):
77         del self.__captured_stdout
78         del self.__captured_stderr
79         self.output_capture.restore_output()
80         unittest.TestCase.tearDown(self)
81
82     def assertStdout(self, expected_stdout):
83         self.assertEquals(expected_stdout, self.__captured_stdout.getvalue())
84
85     def assertStderr(self, expected_stderr):
86         self.assertEquals(expected_stderr, self.__captured_stderr.getvalue())