Patch selectors on Python 3.4. Fixes #591

changelog.rst

@@ -17,7 +17,8 @@ Unreleased
   ``gevent.pool.Group``/``Pool`` and the builtin ``apply`` function.
   This obsoletes the undocumented ``apply_e`` function. Original PR
   #556 by Robert Estelle.
-
+- Monkey-patch the ``selectors`` module from ``patch_all`` and
+  ``patch_select`` on Python 3.4. See #591.
 
 1.1a1 (Jun 29, 2015)
 ====================

gevent/monkey.py

@@ -204,7 +204,8 @@ def patch_ssl():
 def patch_select(aggressive=True):
     """Replace :func:`select.select` with :func:`gevent.select.select`.
 
-    If aggressive is true (the default), also remove other blocking functions the :mod:`select`.
+    If ``aggressive`` is true (the default), also remove other blocking functions from :mod:`select`
+    and (on Python 3.4 and above) :mod:`selectors`.
     """
     patch_module('select')
     if aggressive:
@@ -219,7 +220,8 @@ def patch_select(aggressive=True):
 
     if sys.version_info[:2] >= (3, 4):
         # Python 3 wants to use `select.select` as a member function,
-        # leading to this error in selectors.py
+        # leading to this error in selectors.py (because gevent.select.select is
+        # not a builtin and doesn't get the magic auto-static that they do)
         #    r, w, _ = self._select(self._readers, self._writers, [], timeout)
         #    TypeError: select() takes from 3 to 4 positional arguments but 5 were given
         select = __import__('select')
@@ -229,6 +231,15 @@ def patch_select(aggressive=True):
                 return select.select(*args, **kwargs)
             selectors.SelectSelector._select = _select
 
+        if aggressive:
+            # If `selectors` had already been imported before we removed
+            # select.poll|epoll|kqueue, these may have been defined in terms
+            # of those functions. They'll fail at runtime.
+            remove_item(selectors, 'PollSelector')
+            remove_item(selectors, 'EpollSelector')
+            remove_item(selectors, 'KqueueSelector')
+            selectors.DefaultSelector = selectors.SelectSelector
+
 
 def patch_subprocess():
     patch_module('subprocess')

greentest/3.4/version

+3.4.3

greentest/test___monkey_patching.py

@@ -21,7 +21,8 @@ def get_absolute_pythonpath():
 def TESTRUNNER(tests=None):
     if not os.path.exists(directory):
         return
-    preferred_version = open(os.path.join(directory, 'version')).read().strip()
+    with open(os.path.join(directory, 'version')) as f:
+        preferred_version = f.read().strip()
     if preferred_version != version:
         util.log('WARNING: The tests in %s/ are from version %s and your Python is %s', directory, preferred_version, version)
 

greentest/testrunner.py

@@ -24,7 +24,7 @@ RUN_ALONE = [
 ]
 
 
-def run_many(tests, expected=None, failfast=False):
+def run_many(tests, expected=(), failfast=False):
     global NWORKERS
     start = time.time()
     total = 0