Fix integration test exception handling

Under 9ec134996a the exception
handling of the test_runners was changed to do a bare
raise of the original test failing exception. This was
done to preserve the original traceback. This had the
unintended side effect of allowing exceptions in the error
handling and log reporting code to be raised as the test
case failing exception.

This commit fixes the exception handling to save off the
exc_info and re-raise the original exception with original
traceback.

Change-Id: I13bcf194bb289749ec289216f2541d4923f5f2bf

integration/tests/integration/int_tests.py

@@ -251,8 +251,10 @@ def run_main(test_importer):
         # Turn off the following "feature" of the unittest module in case
         # we want to start a REPL.
         sys.exit = lambda x: None
+
     print("Integration tests are temporarily disabled")
     return 0
+
     proboscis.TestProgram(argv=nose_args, groups=groups, config=c,
                           testRunner=MAIN_RUNNER).run_and_exit()
     sys.stdout = sys.__stdout__

trove/tests/scenario/runners/test_runners.py

@@ -20,6 +20,7 @@ import netaddr
 import os
 import proboscis
 import six
+import sys
 import time as timer
 import types
 
@@ -249,6 +250,7 @@ class LogOnFail(type):
             except proboscis.SkipTest:
                 raise
             except Exception:
+                (extype, exvalue, extb) = sys.exc_info()
                 msg_prefix = "*** LogOnFail: "
                 if inst_ids:
                     report.log(msg_prefix + "Exception detected, "
@@ -276,7 +278,7 @@ class LogOnFail(type):
 
                 # Only report on the first error that occurs
                 mcs.reset_inst_ids()
-                raise
+                six.reraise(extype, exvalue, extb)
 
         return wrapper