Fix import errors with ``python -m unittest``.

Running standard unittest on the test suite resulted in 89 ImportErrors
because ``import DocutilsTestSupport was used to set up sys.path()
but the module could not be found on the original sys.path().

git-svn-id: https://svn.code.sf.net/p/docutils/code/trunk@9274 929543f6-e4f2-0310-98a6-ba3bd3dd1d04

1 files changed, 6 insertions, 1 deletions

diff --git a/docutils/test/test_transforms/test_transitions.py b/docutils/test/test_transforms/test_transitions.py
index dd01a2f8a..56bbc4286 100755
--- a/docutils/test/test_transforms/test_transitions.py
+++ b/docutils/test/test_transforms/test_transitions.py
@@ -8,9 +8,14 @@
 Test module for misc.Transitions transform.
 """
 
+from pathlib import Path
+import sys
 import unittest
 
-from test import DocutilsTestSupport  # NoQA: F401
+if __name__ == '__main__':
+    # prepend the "docutils root" to the Python library path
+    # so we import the local `docutils` package.
+    sys.path.insert(0, str(Path(__file__).parents[2]))
 
 from docutils.frontend import get_default_settings
 from docutils.parsers.rst import Parser