1 files changed, 74 insertions, 0 deletions
diff --git a/lib/testtools/testtools/testsuite.py b/lib/testtools/testtools/testsuite.py
new file mode 100644
index 0000000000..26b193799b
--- /dev/null
+++ b/lib/testtools/testtools/testsuite.py
@@ -0,0 +1,74 @@
+# Copyright (c) 2009 Jonathan M. Lange. See LICENSE for details.
+
+"""Test suites and related things."""
+
+__metaclass__ = type
+__all__ = [
+  'ConcurrentTestSuite',
+  ]
+
+try:
+    import Queue
+except ImportError:
+    import queue as Queue
+import threading
+import unittest
+
+import testtools
+
+
+class ConcurrentTestSuite(unittest.TestSuite):
+    """A TestSuite whose run() calls out to a concurrency strategy."""
+
+    def __init__(self, suite, make_tests):
+        """Create a ConcurrentTestSuite to execute suite.
+
+        :param suite: A suite to run concurrently.
+        :param make_tests: A helper function to split the tests in the
+            ConcurrentTestSuite into some number of concurrently executing
+            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.
+        """
+        super(ConcurrentTestSuite, self).__init__([suite])
+        self.make_tests = make_tests
+
+    def run(self, result):
+        """Run the tests concurrently.
+
+        This calls out to the provided make_tests helper, and then serialises
+        the results so that result only sees activity from one TestCase at
+        a time.
+
+        ConcurrentTestSuite provides no special mechanism to stop the tests
+        returned by make_tests, it is up to the make_tests to honour the
+        shouldStop attribute on the result object they are run with, which will
+        be set if an exception is raised in the thread which
+        ConcurrentTestSuite.run is called in.
+        """
+        tests = self.make_tests(self)
+        try:
+            threads = {}
+            queue = Queue.Queue()
+            result_semaphore = threading.Semaphore(1)
+            for test in tests:
+                process_result = testtools.ThreadsafeForwardingResult(result,
+                    result_semaphore)
+                reader_thread = threading.Thread(
+                    target=self._run_test, args=(test, process_result, queue))
+                threads[test] = reader_thread, process_result
+                reader_thread.start()
+            while threads:
+                finished_test = queue.get()
+                threads[finished_test][0].join()
+                del threads[finished_test]
+        except:
+            for thread, process_result in threads.values():
+                process_result.stop()
+            raise
+
+    def _run_test(self, test, process_result, queue):
+        try:
+            test.run(process_result)
+        finally:
+            queue.put(test)