Fix for bug #184054: MappingStorage used to raise a KeyError during `load`

instead of a POSKeyError.

src/CHANGES.txt

@@ -37,6 +37,9 @@ New Features
 Bugs Fixed
 ----------
 
+- Fix for bug #184054: MappingStorage used to raise a KeyError during `load`
+  instead of a POSKeyError.
+
 - Fixed bug in Connection.TmpStore: load() would not defer to the backend
   storage for loading blobs.
 

src/ZODB/MappingStorage.py

@@ -58,8 +58,11 @@ class MappingStorage(BaseStorage):
     def load(self, oid, version):
         self._lock_acquire()
         try:
-            p = self._index[oid]
-            return p[8:], p[:8] # pickle, serial
+            try:
+                p = self._index[oid]
+                return p[8:], p[:8] # pickle, serial
+            except KeyError:
+                raise POSException.POSKeyError(oid)
         finally:
             self._lock_release()
 

src/ZODB/tests/testConnection.py

@@ -209,12 +209,12 @@ class UserMethodTests(unittest.TestCase):
         >>> obj._p_state
         0
 
-        A request for an object that doesn't exist will raise a KeyError.
+        A request for an object that doesn't exist will raise a POSKeyError.
 
         >>> cn.get(p64(1))
         Traceback (most recent call last):
           ...
-        KeyError: '\x00\x00\x00\x00\x00\x00\x00\x01'
+        POSKeyError: 0x01
         """
 
     def test_close(self):