1 files changed, 20 insertions, 5 deletions

diff --git a/lib/testtools/testtools/testsuite.py b/lib/testtools/testtools/testsuite.py
index 18de8b89e1..41eb6f7d3a 100644
--- a/lib/testtools/testtools/testsuite.py
+++ b/lib/testtools/testtools/testsuite.py
@@ -33,7 +33,7 @@ def iterate_tests(test_suite_or_case):
 class ConcurrentTestSuite(unittest.TestSuite):
     """A TestSuite whose run() calls out to a concurrency strategy."""
 
-    def __init__(self, suite, make_tests):
+    def __init__(self, suite, make_tests, wrap_result=None):
         """Create a ConcurrentTestSuite to execute suite.
 
         :param suite: A suite to run concurrently.
@@ -42,9 +42,24 @@ class ConcurrentTestSuite(unittest.TestSuite):
             sub-suites. make_tests must take a suite, and return an iterable
             of TestCase-like object, each of which must have a run(result)
             method.
+        :param wrap_result: An optional function that takes a thread-safe
+            result and a thread number and must return a ``TestResult``
+            object. If not provided, then ``ConcurrentTestSuite`` will just
+            use a ``ThreadsafeForwardingResult`` wrapped around the result
+            passed to ``run()``.
         """
         super(ConcurrentTestSuite, self).__init__([suite])
         self.make_tests = make_tests
+        if wrap_result:
+            self._wrap_result = wrap_result
+
+    def _wrap_result(self, thread_safe_result, thread_number):
+        """Wrap a thread-safe result before sending it test results.
+
+        You can either override this in a subclass or pass your own
+        ``wrap_result`` in to the constructor.  The latter is preferred.
+        """
+        return thread_safe_result
 
     def run(self, result):
         """Run the tests concurrently.
@@ -63,10 +78,10 @@ class ConcurrentTestSuite(unittest.TestSuite):
         try:
             threads = {}
             queue = Queue()
-            result_semaphore = threading.Semaphore(1)
-            for test in tests:
-                process_result = testtools.ThreadsafeForwardingResult(result,
-                    result_semaphore)
+            semaphore = threading.Semaphore(1)
+            for i, test in enumerate(tests):
+                process_result = self._wrap_result(
+                    testtools.ThreadsafeForwardingResult(result, semaphore), i)
                 reader_thread = threading.Thread(
                     target=self._run_test, args=(test, process_result, queue))
                 threads[test] = reader_thread, process_result