Add changelog and test for #687

changelog.rst

@@ -21,10 +21,14 @@
   callback function behave like the CPython implementation: the
   exception is printed, and the rest of the callbacks continue
   processing.
-- If a Hub object with active watchers, was destroyed and then another
-  one created for the same thread which itself was then destroyed with
+- If a Hub object with active watchers was destroyed and then another
+  one created for the same thread, which itself was then destroyed with
   ``destroy_loop=True``, the process could crash. Documented in
   :issue:`237` and fix based on :pr:`238`, both by Jan-Philip Gehrcke.
+- Python 3: Initializing gevent's hub for the first time in a native
+  background thread created during import could fail with
+  ``AttributeError`` and ``ImportError``. Reported in :issue:`687` by
+  Gregory Petukhov.
 
 1.1b6 (Oct 17, 2015)
 ====================

gevent/hub.py

@@ -67,6 +67,10 @@ threadlocal = thread._local
 class _threadlocal(threadlocal):
 
     def __init__(self):
+        # Use a class with an initializer so that we can test
+        # for 'is None' instead of catching AttributeError, making
+        # the code cleaner and possibly solving some corner cases
+        # (like #687)
         threadlocal.__init__(self)
         self.Hub = None
         self.loop = None

greentest/test__monkey_hub_in_thread.py

+from gevent.monkey import patch_all
+patch_all(thread=False)
+from threading import Thread
+import time
+
+# The first time we init the hub is in the native
+# thread with time.sleep().
+# See #687
+
+
+def func():
+    time.sleep()
+
+
+def main():
+    threads = []
+    for _ in range(2):
+        th = Thread(target=func)
+        th.start()
+        threads.append(th)
+    for th in threads:
+        th.join()
+
+
+if __name__ == '__main__':
+    main()