unittest plugin: prune __unittest marked modules from traces

_pytest/unittest.py

@@ -102,6 +102,10 @@ class TestCaseFunction(pytest.Function):
     def runtest(self):
         self._testcase(result=self)
 
+    def _prunetraceback(self, excinfo):
+        pytest.Function._prunetraceback(self, excinfo)
+        excinfo.traceback = excinfo.traceback.filter(lambda x:not x.frame.f_globals.get('__unittest'))
+
 @pytest.mark.tryfirst
 def pytest_runtest_makereport(item, call):
     if isinstance(item, TestCaseFunction):

testing/test_unittest.py

@@ -396,3 +396,15 @@ def test_djangolike_testcase(testdir):
         "*tearDown()*",
         "*_post_teardown()*",
     ])
+
+
+def test_unittest_not_shown_in_traceback(testdir):
+    testdir.makepyfile("""
+        import unittest
+        class t(unittest.TestCase):
+            def test_hello(self):
+                x = 3
+                self.assertEquals(x, 4)
+    """)
+    res = testdir.runpytest()
+    assert "failUnlessEqual" not in res.stdout.str()