Test failures with Pygments 2.1

[Ryan J Ollos]

The automated tests that ran when committing the fix for #12325 revealed some test case failures. Pygments 2.1 was released on 2016-01-17. Test failures were not seen with Pygments 2.0.2.

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FAIL: test_extra_mimetypes (trac.mimeview.tests.pygments.PygmentsRendererTestCase)
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Traceback (most recent call last):
  File "/Users/rjollos/Documents/Workspace/trac-dev/teo-rjollos.git/trac/mimeview/tests/pygments.py", line 123, in test_extra_mimetypes
    mimeview.get_mimetype('file.ini'))
AssertionError: 'text/x-ini; charset=utf-8' != u'text/inf; charset=utf-8'

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FAIL: test_python_hello (trac.mimeview.tests.pygments.PygmentsRendererTestCase)
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Traceback (most recent call last):
  File "/Users/rjollos/Documents/Workspace/trac-dev/teo-rjollos.git/trac/mimeview/tests/pygments.py", line 74, in test_python_hello
    self._test('python_hello', result)
  File "/Users/rjollos/Documents/Workspace/trac-dev/teo-rjollos.git/trac/mimeview/tests/pygments.py", line 62, in _test
    self.assertEqual(exp, res)
AssertionError: '        <span class="k">return</span> <span class="s">"Hello World!"</span>' != '        <span class="k">return</span> <span class="s2">"Hello World!"</span>'

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FAIL: test_python_hello_mimeview (trac.mimeview.tests.pygments.PygmentsRendererTestCase)
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Traceback (most recent call last):
  File "/Users/rjollos/Documents/Workspace/trac-dev/teo-rjollos.git/trac/mimeview/tests/pygments.py", line 85, in test_python_hello_mimeview
    self._test('python_hello_mimeview', result)
  File "/Users/rjollos/Documents/Workspace/trac-dev/teo-rjollos.git/trac/mimeview/tests/pygments.py", line 62, in _test
    self.assertEqual(exp, res)
AssertionError: '        <span class="k">return</span> <span class="s">"Hello World!"</span>' != '        <span class="k">return</span> <span class="s2">"Hello World!"</span>'

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Ran 1795 tests in 108.513s

FAILED (failures=3)
make: *** [unit-test] Error 1