.

bigfile/file_zodb.py

@@ -804,7 +804,7 @@ class _ZBigFileH(object):
         #
         # the reason we do it here, is that if we don't and Connection was not
         # yet joined to transaction (i.e. no changes were made to Connection's
-        # objects), as storeblk() running inside commit will case changes to
+        # objects), as storeblk() running inside commit will cause changes to
         # ZODB objects, zconn will want to join transaction, and that is
         # currently forbidden.
         #

lib/tests/test_zodb.py

@@ -250,39 +250,57 @@ def test_zconn_at():
     conn1 = db.open()
     assert zconn_at(conn1) == at0
 
+    # open another simultaneous connection
+    conn2 = db.open()
+    assert zconn_at(conn2) == at0
+
     # commit
     root1 = conn1.root()
     root1['z'] = 1
     transaction.commit()
 
-    # after commit connection view is updated
+    # after commit conn1 view is updated; conn2 view stays @at0
     zsync(stor)
     at1 = stor.lastTransaction()
     assert zconn_at(conn1) == at1
+    assert zconn_at(conn2) == at0
 
-    # reopen -> view @at1
+    # reopen conn1 -> view @at1
     conn1.close()
     with raises(POSException.ConnectionStateError):
         zconn_at(conn1)
-    conn2 = db.open()
-    assert conn2 is conn1   # returned from DB pool
-    assert zconn_at(conn2) == at1
-    conn2.close()
+    assert zconn_at(conn2) == at0
+    conn1_ = db.open()
+    assert conn1_ is conn1   # returned from DB pool
+    assert zconn_at(conn1) == at1
+    assert zconn_at(conn2) == at0
+    conn1.close()
 
     # commit empty transaction - view stays in sync with storage head
     #
     # TODO zconn_at after empty commit (with fs1 currently gives future tid,
     # but db is not updated and wcfs client resync to that future tid hangs)
-    conn3 = db.open()
-    assert conn3 is conn2   # from DB pool
-    assert zconn_at(conn3) == at1
+    conn1_ = db.open()
+    assert conn1_ is conn2   # from DB pool
+    assert zconn_at(conn1) == at1
+    assert zconn_at(conn2) == at0
     transaction.commit()
 
     zsync(stor)
     at1_ = stor.lastTransaction()
-    assert zconn_at(conn3) == at1_
+    assert zconn_at(conn1) == at1_
+    assert zconn_at(conn2) == at0
+
+
+    # reopen conn2 -> view upated to @at1_
+    conn2.close()
+    conn2_ = db.open()
+    assert conn2_ is conn2  # from DB pool
+    assert zconn_at(conn1) == at1_
+    assert zconn_at(conn2) == at1_
 
-    conn3.close()
+    conn1.close()
+    conn2.close()
 
 
     # TODO commit -> know head -> open conn1,