[Python-checkins] r78141 - in python/trunk: Doc/library/shelve.rst Lib/test/test_shelve.py Misc/ACKS

r.david.murray python-checkins at python.org
Thu Feb 11 02:38:42 CET 2010


Author: r.david.murray
Date: Thu Feb 11 02:38:42 2010
New Revision: 78141

Log:
Issue 5754:  tweak shelve doc wording to make it clearer that even when
writeback=True values are written to the backing store when assigned to
the shelf.  Add test to confirm that this happens.  Doc patch and added
test by Robert Lehmann.  I also fixed the cross references to the sync
and close methods.


Modified:
   python/trunk/Doc/library/shelve.rst
   python/trunk/Lib/test/test_shelve.py
   python/trunk/Misc/ACKS

Modified: python/trunk/Doc/library/shelve.rst
==============================================================================
--- python/trunk/Doc/library/shelve.rst	(original)
+++ python/trunk/Doc/library/shelve.rst	Thu Feb 11 02:38:42 2010
@@ -30,14 +30,15 @@
 
    Because of Python semantics, a shelf cannot know when a mutable
    persistent-dictionary entry is modified.  By default modified objects are
-   written only when assigned to the shelf (see :ref:`shelve-example`).  If the
-   optional *writeback* parameter is set to *True*, all entries accessed are
-   cached in memory, and written back on :meth:`sync` and :meth:`close`; this
-   can make it handier to mutate mutable entries in the persistent dictionary,
-   but, if many entries are accessed, it can consume vast amounts of memory for
-   the cache, and it can make the close operation very slow since all accessed
-   entries are written back (there is no way to determine which accessed entries
-   are mutable, nor which ones were actually mutated).
+   written *only* when assigned to the shelf (see :ref:`shelve-example`).  If the
+   optional *writeback* parameter is set to *True*, all entries accessed are also
+   cached in memory, and written back on :meth:`~Shelf.sync` and
+   :meth:`~Shelf.close`; this can make it handier to mutate mutable entries in
+   the persistent dictionary, but, if many entries are accessed, it can consume
+   vast amounts of memory for the cache, and it can make the close operation
+   very slow since all accessed entries are written back (there is no way to
+   determine which accessed entries are mutable, nor which ones were actually
+   mutated).
 
    .. note::
 

Modified: python/trunk/Lib/test/test_shelve.py
==============================================================================
--- python/trunk/Lib/test/test_shelve.py	(original)
+++ python/trunk/Lib/test/test_shelve.py	Thu Feb 11 02:38:42 2010
@@ -90,6 +90,17 @@
         self.assertEqual(len(d1), 1)
         self.assertEqual(len(d2), 1)
 
+    def test_writeback_also_writes_immediately(self):
+        # Issue 5754
+        d = {}
+        s = shelve.Shelf(d, writeback=True)
+        s['key'] = [1]
+        p1 = d['key']  # Will give a KeyError if backing store not updated
+        s['key'].append(2)
+        s.close()
+        p2 = d['key']
+        self.assertNotEqual(p1, p2)  # Write creates new object in store
+
 
 from test import mapping_tests
 

Modified: python/trunk/Misc/ACKS
==============================================================================
--- python/trunk/Misc/ACKS	(original)
+++ python/trunk/Misc/ACKS	Thu Feb 11 02:38:42 2010
@@ -444,6 +444,7 @@
 Vincent Legoll
 Kip Lehman
 Joerg Lehmann
+Robert Lehmann
 Luke Kenneth Casson Leighton
 Marc-Andre Lemburg
 John Lenton


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