refine unittest support to also work with twisted trial test cases better by

introducing a slightly hackish way to report a failure upstream

_pytest/unittest.py

@@ -33,16 +33,40 @@ class UnitTestCase(pytest.Class):
             meth()
 
 class TestCaseFunction(pytest.Function):
+    _excinfo = None
     def setup(self):
         pass
     def teardown(self):
         pass
     def startTest(self, testcase):
         pass
+
+    def _addexcinfo(self, rawexcinfo):
+        #__tracebackhide__ = True
+        assert rawexcinfo
+        try:
+            self._excinfo = py.code.ExceptionInfo(rawexcinfo)
+        except TypeError:
+            try:
+                try:
+                    l = py.std.traceback.format_exception(*rawexcinfo)
+                    l.insert(0, "NOTE: Incompatible Exception Representation, "
+                        "displaying natively:\n\n")
+                    pytest.fail("".join(l), pytrace=False)
+                except (pytest.fail.Exception, KeyboardInterrupt):
+                    raise
+                except:
+                    pytest.fail("ERROR: Unknown Incompatible Exception "
+                        "representation:\n%r" %(rawexcinfo,), pytrace=False)
+            except pytest.fail.Exception:
+                self._excinfo = py.code.ExceptionInfo()
+            except KeyboardInterrupt:
+                raise
+
     def addError(self, testcase, rawexcinfo):
-        py.builtin._reraise(*rawexcinfo)
+        self._addexcinfo(rawexcinfo)
     def addFailure(self, testcase, rawexcinfo):
-        py.builtin._reraise(*rawexcinfo)
+        self._addexcinfo(rawexcinfo)
     def addSuccess(self, testcase):
         pass
     def stopTest(self, testcase):
@@ -50,3 +74,11 @@ class TestCaseFunction(pytest.Function):
     def runtest(self):
         testcase = self.parent.obj(self.name)
         testcase(result=self)
+
+@pytest.mark.tryfirst
+def pytest_runtest_makereport(item, call):
+    if isinstance(item, TestCaseFunction):
+        if item._excinfo:
+            call.excinfo = item._excinfo
+            item._excinfo = None
+            del call.result