libev follows libuv by not updating the loop time in a timer by default. A...

libev follows libuv by not updating the loop time in a timer by default. A Timeout that we use internally still does this though.

CHANGES.rst

@@ -190,18 +190,19 @@ libuv
     happen in a different order, and timers may easily be off by up to
     half of the supposed 1ms resolution. See :issue:`1057`.
 
-  - Starting timers does not update the loop's time by default. This
-    is because, unlike libev, a timer callback can cause other timer
-    callbacks to be run if they expire because the loop's time
-    updated, without cycling the event loop. See :issue:`1057`.
+  - Starting a ``timer`` watcher does not update the loop's time by
+    default. This is because, unlike libev, a timer callback can cause
+    other timer callbacks to be run if they expire because the loop's
+    time updated, without cycling the event loop. See :issue:`1057`.
 
-    .. note:: libev might be changed to follow this behaviour.
+    libev has also been changed to follow this behaviour.
 
   Again, this is extremely experimental and all of it is subject to
   change.
 
   See :issue:`790` for history and more in-depth discussion.
 
+
 1.2.2 (2017-06-05)
 ==================
 

src/gevent/_ffi/watcher.py

@@ -423,7 +423,7 @@ class IoMixin(object):
 class TimerMixin(object):
     _watcher_type = 'timer'
 
-    update_loop_time_on_start = True
+    update_loop_time_on_start = False
 
     def __init__(self, loop, after=0.0, repeat=0.0, ref=True, priority=None):
         if repeat < 0.0:
@@ -441,7 +441,8 @@ class TimerMixin(object):
             # runs for a very long time without entering the event
             # loop, updating libev's idea of the current time is a
             # good idea."
-            # So do we really need to default to true?
+            # 1.3 changed the default for this to False. Note that
+            # starting Timeout objects internally still sets this to true.
             self._update_now()
         super(TimerMixin, self).start(callback, *args)
 

src/gevent/libev/corecext.ppyx

@@ -893,13 +893,17 @@ cdef public class timer(watcher) [object PyGeventTimerObject, type PyGeventTimer
 
     WATCHER_BASE(timer)
 
-    def start(self, object callback, *args, update=True):
+    update_loop_time_on_start = False
+
+    def start(self, object callback, *args, update=None):
         CHECK_LOOP2(self.loop)
         if callback is None:
             raise TypeError('callback must be callable, not None')
         self.callback = callback
         self.args = args
         LIBEV_UNREF
+        if update is None:
+            update = self.update_loop_time_on_start
         if update:
             libev.ev_now_update(self.loop._ptr)
         libev.ev_timer_start(self.loop._ptr, &self._watcher)

src/gevent/timeout.py

@@ -191,6 +191,7 @@ class Timeout(BaseException):
             return _FakeTimer
         # If we don't update the time here (and the timer watcher doesn't),
         # as under libuv, then certain tests hang, notably the monkey-patched test_telnetlib
+        # in test_read_eager_A. libev does not demonstrate this behaviour.
         return Timeout.start_new(timeout, exception, _update=True)
 
     @property

src/greentest/test__pywsgi.py

@@ -64,9 +64,8 @@ try:
 except ImportError:
     pass
 
-if greentest.PYPY or PY3:
-    from errno import ECONNRESET
-    CONN_ABORTED_ERRORS.append(ECONNRESET)
+from errno import ECONNRESET
+CONN_ABORTED_ERRORS.append(ECONNRESET)
 
 REASONS = {200: 'OK',
            500: 'Internal Server Error'}
@@ -92,7 +91,7 @@ def read_headers(fd):
         except:
             print('Failed to split: %r' % (line, ))
             raise
-        assert key.lower() not in [x.lower() for x in headers.keys()], 'Header %r:%r sent more than once: %r' % (key, value, headers)
+        assert key.lower() not in {x.lower() for x in headers}, 'Header %r:%r sent more than once: %r' % (key, value, headers)
         headers[key] = value
     return response_line, headers
 
@@ -375,12 +374,17 @@ class CommonTests(TestCase):
         fd.write('GET / HTTP/1.1\r\nHost: localhost\r\nConnection: close\r\n\r\n')
         read_http(fd)
         fd.write('GET / HTTP/1.1\r\nHost: localhost\r\n\r\n')
+        # This may either raise, or it may return an empty response,
+        # depend on timing and the Python version.
         try:
             result = fd.readline()
-            assert not result, 'The remote side is expected to close the connection, but it send %r' % (result, )
         except socket.error as ex:
             if ex.args[0] not in CONN_ABORTED_ERRORS:
                 raise
+        else:
+            self.assertFalse(
+                result,
+                'The remote side is expected to close the connection, but it sent %r' % (result,))
 
     def SKIP_test_006_reject_long_urls(self):
         fd = self.makefile()
@@ -1413,16 +1417,16 @@ class Handler(pywsgi.WSGIHandler):
     def read_requestline(self):
         data = self.rfile.read(7)
         if data[0] == b'<'[0]:
-            try:
-                data += self.rfile.read(15)
-                if data.lower() == b'<policy-file-request/>':
-                    self.socket.sendall(b'HELLO')
-                else:
-                    self.log_error('Invalid request: %r', data)
-            finally:
-                self.socket.shutdown(socket.SHUT_WR)
-                self.socket.close()
-                self.socket = None
+            # Returning nothing stops handle_one_request()
+            # Note that closing or even deleting self.socket() here
+            # can lead to the read side throwing Connection Reset By Peer,
+            # depending on the Python version and OS
+            data += self.rfile.read(15)
+            if data.lower() == b'<policy-file-request/>':
+                self.socket.sendall(b'HELLO')
+            else:
+                self.log_error('Invalid request: %r', data)
+            return None
         else:
             return data + self.rfile.readline()
 
@@ -1452,6 +1456,7 @@ class TestHandlerSubclass(TestCase):
         read_http(fd)
 
         fd = self.makefile()
+        # Trigger an error
         fd.write('<policy-file-XXXuest/>\x00')
         fd.flush()
         self.assertEqual(fd.read(), b'')