Update to persistent >= 4.2.3. (#9)

* Update to persistent >= 4.2.3.

* Use the version of `PickleCache` matching the used `persistent` variant.

CHANGES.rst

@@ -4,6 +4,7 @@ Changelog
 3.0b3 (unreleased)
 ------------------
 
+- Make tests compatible with `persistent >= 4.2.3`.
 
 3.0b2 (2017-11-27)
 ------------------

src/Persistence/tests/test_persistent.py

@@ -19,7 +19,7 @@
 
 from Persistence import IS_PYPY, IS_PURE
 from Persistence import Persistent
-from persistent.picklecache import PickleCache
+from persistent import PickleCache
 from persistent.TimeStamp import TimeStamp
 
 
@@ -108,29 +108,18 @@ def test_oid_jar_attrs(self):
 
         self.jar.add(obj)
 
-        if not (IS_PURE or IS_PYPY):
-            # Can change oid of cache object since persistent 4.0.8
+        # Can't change oid of cache object.
+        with self.assertRaises(ValueError):
             del obj._p_oid
+
+        with self.assertRaises(ValueError):
             obj._p_oid = 12
+
+        with self.assertRaises(ValueError):
             del obj._p_jar
+
+        with self.assertRaises(ValueError):
             obj._p_jar = 12
-        else:
-            # Can't change oid of cache object.
-            def deloid():
-                del obj._p_oid
-            self.assertRaises(ValueError, deloid)
-
-            def setoid():
-                obj._p_oid = 12
-            self.assertRaises(ValueError, setoid)
-
-            def deloid():
-                del obj._p_jar
-            self.assertRaises(ValueError, deloid)
-
-            def setoid():
-                obj._p_jar = 12
-            self.assertRaises(ValueError, setoid)
 
     def testChanged(self):
         obj = P()

tox.ini

@@ -15,7 +15,7 @@ envlist =
 commands =
     {envbindir}/buildout -c {toxinidir}/buildout.cfg buildout:directory={envdir} buildout:develop={toxinidir} bootstrap
     {envbindir}/buildout -c {toxinidir}/buildout.cfg buildout:directory={envdir} buildout:develop={toxinidir}
-    {envbindir}/test {posargs:-v1}
+    {envbindir}/test {posargs:-vc1}
 skip_install = true
 deps =
     setuptools==33.1.1