Translate addUnexpectedSuccess to addFailure instead of addSuccess.

testtools/testresult/real.py

@@ -11,6 +11,7 @@ __all__ = [
     ]
 
 import datetime
+import sys
 import unittest
 
 from testtools.compat import _format_exc_info, str_is_unicode, _u
@@ -432,7 +433,10 @@ class ExtendedToOriginalDecorator(object):
     def addUnexpectedSuccess(self, test, details=None):
         outcome = getattr(self.decorated, 'addUnexpectedSuccess', None)
         if outcome is None:
-            return self.decorated.addSuccess(test)
+            try:
+                test.fail("")
+            except test.failureException:
+                return self.addFailure(test, sys.exc_info())
         if details is not None:
             try:
                 return outcome(test, details=details)

testtools/tests/test_testresult.py

@@ -810,7 +810,7 @@ class TestExtendedToOriginalAddSkip(
         self.make_27_result()
         self.check_outcome_details_to_string(self.outcome)
 
-    def test_outcome_Extended_py27_no_reason(self):
+    def test_outcome_Extended_py27_reason(self):
         self.make_27_result()
         self.check_outcome_details_to_arg(self.outcome, 'foo',
             {'reason': Content(UTF8_TEXT, lambda:['foo'])})
@@ -857,9 +857,38 @@ class TestExtendedToOriginalAddSuccess(
 
 
 class TestExtendedToOriginalAddUnexpectedSuccess(
-    TestExtendedToOriginalAddSuccess):
+    TestExtendedToOriginalResultDecoratorBase):
 
     outcome = 'addUnexpectedSuccess'
+    expected = 'addFailure'
+
+    def test_outcome_Original_py26(self):
+        self.make_26_result()
+        getattr(self.converter, self.outcome)(self)
+        [event] = self.result._events
+        self.assertEqual((self.expected, self), event[:2])
+
+    def test_outcome_Original_py27(self):
+        self.make_27_result()
+        self.check_outcome_nothing(self.outcome)
+
+    def test_outcome_Original_pyextended(self):
+        self.make_extended_result()
+        self.check_outcome_nothing(self.outcome)
+
+    def test_outcome_Extended_py26(self):
+        self.make_26_result()
+        getattr(self.converter, self.outcome)(self)
+        [event] = self.result._events
+        self.assertEqual((self.expected, self), event[:2])
+
+    def test_outcome_Extended_py27(self):
+        self.make_27_result()
+        self.check_outcome_details_to_nothing(self.outcome)
+
+    def test_outcome_Extended_pyextended(self):
+        self.make_extended_result()
+        self.check_outcome_details(self.outcome)
 
 
 class TestExtendedToOriginalResultOtherAttributes(