#165 more accurate asyncio.CancelledError handling

CHANGES.rst

@@ -10,6 +10,12 @@ Changelog
 - Improve log message when client cache is out of sync with server.
   See `issue 142 <https://github.com/zopefoundation/ZEO/issues/142>`_.
 
+- Add support for Python 3.8 and Python 3.9.
+
+- Add more accurate error handling for ``asyncio.CancelledError``.
+  See `issue 165 <https://github.com/zopefoundation/ZEO/issues/165>`_.
+
+
 5.2.2 (2020-08-11)
 ------------------
 

setup.py

@@ -48,6 +48,8 @@ Programming Language :: Python :: 3
 Programming Language :: Python :: 3.5
 Programming Language :: Python :: 3.6
 Programming Language :: Python :: 3.7
+Programming Language :: Python :: 3.8
+Programming Language :: Python :: 3.9
 Programming Language :: Python :: Implementation :: CPython
 Programming Language :: Python :: Implementation :: PyPy
 Topic :: Database

src/ZEO/asyncio/client.py

@@ -410,7 +410,10 @@ class Client(object):
     def _clear_protocols(self, protocol=None):
         for p in self.protocols:
             if p is not protocol:
+                try:
                     p.close()
+                except asyncio.CancelledError:
+                    continue
         self.protocols = ()
 
     def disconnected(self, protocol=None):
@@ -483,7 +486,14 @@ class Client(object):
 
         protocol = self.protocol
         if server_tid is None:
+            try:
                 server_tid = yield protocol.fut('lastTransaction')
+            except ClientDisconnected as exc:
+                # If needed, after consideration more exceptions can be
+                # caught here. Possibly you want to include this into the
+                # following try clause.
+                del self.protocol
+                self.register_failed(protocol, exc)
 
         try:
             cache = self.cache

tox.ini

@@ -4,6 +4,8 @@ envlist =
     py35
     py36
     py37
+    py38
+    py39
     pypy
     pypy3
     simple
@@ -67,6 +69,34 @@ deps =
     {[testenv]deps}
     uvloop
 
+[testenv:py38-mtacceptor]
+setenv =
+    ZEO_MTACCEPTOR=1
+
+[testenv:py38-mtacceptor-msgpack1]
+setenv =
+    ZEO_MTACCEPTOR=1
+    ZEO_MSGPACK=1
+
+[testenv:py38-uvloop]
+deps =
+    {[testenv]deps}
+    uvloop
+
+[testenv:py39-mtacceptor]
+setenv =
+    ZEO_MTACCEPTOR=1
+
+[testenv:py39-mtacceptor-msgpack1]
+setenv =
+    ZEO_MTACCEPTOR=1
+    ZEO_MSGPACK=1
+
+[testenv:py39-uvloop]
+deps =
+    {[testenv]deps}
+    uvloop
+
 [testenv:pypy3-mtacceptor]
 setenv =
     ZEO_MTACCEPTOR=1