Merged revisions 72223 via svnmerge from
svn+ssh://pythondev@svn.python.org/python/trunk
........
r72223 | antoine.pitrou | 2009-05-02 23:13:23 +0200 (sam., 02 mai 2009) | 5 lines
Isue #5084: unpickling now interns the attribute names of pickled objects,
saving memory and avoiding growth in size of subsequent pickles. Proposal
and original patch by Jake McGuire.
........
diff --git a/Lib/pickle.py b/Lib/pickle.py
index 409d4b2..b94b305 100644
--- a/Lib/pickle.py
+++ b/Lib/pickle.py
@@ -1195,7 +1195,15 @@
if isinstance(state, tuple) and len(state) == 2:
state, slotstate = state
if state:
- inst.__dict__.update(state)
+ d = inst.__dict__
+ intern = sys.intern
+ try:
+ for k, v in state.items():
+ d[intern(k)] = v
+ # keys in state don't have to be strings
+ # don't blow up, but don't go out of our way
+ except TypeError:
+ d.update(state)
if slotstate:
for k, v in slotstate.items():
setattr(inst, k, v)
diff --git a/Lib/test/pickletester.py b/Lib/test/pickletester.py
index e3a929f..1585586 100644
--- a/Lib/test/pickletester.py
+++ b/Lib/test/pickletester.py
@@ -932,6 +932,20 @@
"Failed protocol %d: %r != %r"
% (proto, obj, loaded))
+ def test_attribute_name_interning(self):
+ # Test that attribute names of pickled objects are interned when
+ # unpickling.
+ for proto in protocols:
+ x = C()
+ x.foo = 42
+ x.bar = "hello"
+ s = self.dumps(x, proto)
+ y = self.loads(s)
+ x_keys = sorted(x.__dict__)
+ y_keys = sorted(y.__dict__)
+ for x_key, y_key in zip(x_keys, y_keys):
+ self.assertIs(x_key, y_key)
+
# Test classes for reduce_ex
class REX_one(object):
diff --git a/Misc/NEWS b/Misc/NEWS
index f4116ad..00270fd 100644
--- a/Misc/NEWS
+++ b/Misc/NEWS
@@ -109,6 +109,10 @@
Library
-------
+- Issue #5084: unpickling now interns the attribute names of pickled objects,
+ saving memory and avoiding growth in size of subsequent pickles. Proposal
+ and original patch by Jake McGuire.
+
- The json module now works exclusively with str and not bytes.
- Issue #3959: The ipaddr module has been added to the standard library.
diff --git a/Modules/_pickle.c b/Modules/_pickle.c
index e9c4a76..754d132 100644
--- a/Modules/_pickle.c
+++ b/Modules/_pickle.c
@@ -4020,6 +4020,8 @@
/* Set inst.__dict__ from the state dict (if any). */
if (state != Py_None) {
PyObject *dict;
+ PyObject *d_key, *d_value;
+ Py_ssize_t i;
if (!PyDict_Check(state)) {
PyErr_SetString(UnpicklingError, "state is not a dictionary");
@@ -4029,7 +4031,19 @@
if (dict == NULL)
goto error;
- PyDict_Update(dict, state);
+ i = 0;
+ while (PyDict_Next(state, &i, &d_key, &d_value)) {
+ /* normally the keys for instance attributes are
+ interned. we should try to do that here. */
+ Py_INCREF(d_key);
+ if (PyUnicode_CheckExact(d_key))
+ PyUnicode_InternInPlace(&d_key);
+ if (PyObject_SetItem(dict, d_key, d_value) < 0) {
+ Py_DECREF(d_key);
+ goto error;
+ }
+ Py_DECREF(d_key);
+ }
Py_DECREF(dict);
}