--- a/cubicweb/devtools/repotest.py	Fri Mar 10 17:46:06 2017 +0100
+++ b/cubicweb/devtools/repotest.py	Fri Mar 10 17:52:44 2017 +0100
@@ -21,9 +21,9 @@
 """
 from __future__ import print_function
 
+from contextlib import contextmanager
 from pprint import pprint
 
-from logilab.common.decorators import cachedproperty
 from logilab.common.testlib import SkipTest
 
 from cubicweb.devtools.testlib import RepoAccess
@@ -39,7 +39,7 @@
 
 
 def check_plan(self, rql, expected, kwargs=None):
-    with self.session.new_cnx() as cnx:
+    with self._access.cnx() as cnx:
         plan = self._prepare_plan(cnx, rql, kwargs)
         self.planner.build_plan(plan)
         try:
@@ -138,7 +138,6 @@
 from cubicweb.devtools.fake import FakeRepo, FakeConfig, FakeRequest, FakeConnection
 from cubicweb.server import set_debug, debugged
 from cubicweb.server.querier import QuerierHelper
-from cubicweb.server.session import Session
 from cubicweb.server.sources.rql2sql import SQLGenerator, remove_unused_solutions
 
 class RQLGeneratorTC(BaseTestCase):
@@ -193,14 +192,10 @@
 class BaseQuerierTC(TestCase):
     repo = None # set this in concrete class
 
-    @cachedproperty
-    def session(self):
-        return self._access._session
-
     def setUp(self):
         self.o = self.repo.querier
         self._access = RepoAccess(self.repo, 'admin', FakeRequest)
-        self.ueid = self.session.user.eid
+        self.ueid = self._access._user.eid
         assert self.ueid != -1
         self.repo._type_cache = {} # clear cache
         self.maxeid = self.get_max_eid()
@@ -208,18 +203,18 @@
         self._dumb_sessions = []
 
     def get_max_eid(self):
-        with self.session.new_cnx() as cnx:
+        with self._access.cnx() as cnx:
             return cnx.execute('Any MAX(X)')[0][0]
 
     def cleanup(self):
-        with self.session.new_cnx() as cnx:
+        with self._access.cnx() as cnx:
             cnx.execute('DELETE Any X WHERE X eid > %s' % self.maxeid)
             cnx.commit()
 
     def tearDown(self):
         undo_monkey_patch()
         self.cleanup()
-        assert self.session.user.eid != -1
+        assert self._access._user.eid != -1
 
     def set_debug(self, debug):
         set_debug(debug)
@@ -250,17 +245,17 @@
         rqlst.solutions = remove_unused_solutions(rqlst, rqlst.solutions, self.repo.schema)[0]
         return rqlst
 
+    @contextmanager
     def user_groups_session(self, *groups):
         """lightweight session using the current user with hi-jacked groups"""
-        # use self.session.user.eid to get correct owned_by relation, unless explicit eid
-        with self.session.new_cnx() as cnx:
-            user_eid = self.session.user.eid
-            session = Session(self.repo._build_user(cnx, user_eid), self.repo)
-            session.data['%s-groups' % user_eid] = set(groups)
-            return session
+        # use cnx.user.eid to get correct owned_by relation, unless explicit eid
+        with self._access.cnx() as cnx:
+            user_eid = cnx.user.eid
+            cnx.user._cw.data['groups-%s' % user_eid] = set(groups)
+            yield cnx
 
     def qexecute(self, rql, args=None, build_descr=True):
-        with self.session.new_cnx() as cnx:
+        with self._access.cnx() as cnx:
             try:
                 return self.o.execute(cnx, rql, args, build_descr)
             finally: