changeset:   96537:eff50d543c79
branch:      3.5
parent:      96535:19dbee688a30
user:        Serhiy Storchaka <storchaka@gmail.com>
date:        Mon Jun 08 11:19:24 2015 +0300
files:       Lib/test/test_functools.py Misc/NEWS Modules/_functoolsmodule.c
description:
Issue #14373: C implementation of functools.lru_cache() now can be used with
methods.


diff -r 19dbee688a30 -r eff50d543c79 Lib/test/test_functools.py
--- a/Lib/test/test_functools.py	Mon Jun 08 11:14:31 2015 +0300
+++ b/Lib/test/test_functools.py	Mon Jun 08 11:19:24 2015 +0300
@@ -1203,6 +1203,37 @@
             def f():
                 pass
 
+    def test_lru_method(self):
+        class X(int):
+            f_cnt = 0
+            @self.module.lru_cache(2)
+            def f(self, x):
+                self.f_cnt += 1
+                return x*10+self
+        a = X(5)
+        b = X(5)
+        c = X(7)
+        self.assertEqual(X.f.cache_info(), (0, 0, 2, 0))
+
+        for x in 1, 2, 2, 3, 1, 1, 1, 2, 3, 3:
+            self.assertEqual(a.f(x), x*10 + 5)
+        self.assertEqual((a.f_cnt, b.f_cnt, c.f_cnt), (6, 0, 0))
+        self.assertEqual(X.f.cache_info(), (4, 6, 2, 2))
+
+        for x in 1, 2, 1, 1, 1, 1, 3, 2, 2, 2:
+            self.assertEqual(b.f(x), x*10 + 5)
+        self.assertEqual((a.f_cnt, b.f_cnt, c.f_cnt), (6, 4, 0))
+        self.assertEqual(X.f.cache_info(), (10, 10, 2, 2))
+
+        for x in 2, 1, 1, 1, 1, 2, 1, 3, 2, 1:
+            self.assertEqual(c.f(x), x*10 + 7)
+        self.assertEqual((a.f_cnt, b.f_cnt, c.f_cnt), (6, 4, 5))
+        self.assertEqual(X.f.cache_info(), (15, 15, 2, 2))
+
+        self.assertEqual(a.f.cache_info(), X.f.cache_info())
+        self.assertEqual(b.f.cache_info(), X.f.cache_info())
+        self.assertEqual(c.f.cache_info(), X.f.cache_info())
+
 class TestLRUC(TestLRU, unittest.TestCase):
     module = c_functools
 
diff -r 19dbee688a30 -r eff50d543c79 Misc/NEWS
--- a/Misc/NEWS	Mon Jun 08 11:14:31 2015 +0300
+++ b/Misc/NEWS	Mon Jun 08 11:19:24 2015 +0300
@@ -15,6 +15,9 @@
 Library
 -------
 
+- Issue #14373: C implementation of functools.lru_cache() now can be used with
+  methods.
+
 - Issue #8232: webbrowser support incomplete on Windows. Patch by Brandon
   Milam
 
diff -r 19dbee688a30 -r eff50d543c79 Modules/_functoolsmodule.c
--- a/Modules/_functoolsmodule.c	Mon Jun 08 11:14:31 2015 +0300
+++ b/Modules/_functoolsmodule.c	Mon Jun 08 11:19:24 2015 +0300
@@ -1004,6 +1004,16 @@
 }
 
 static PyObject *
+lru_cache_descr_get(PyObject *self, PyObject *obj, PyObject *type)
+{
+    if (obj == Py_None || obj == NULL) {
+        Py_INCREF(self);
+        return self;
+    }
+    return PyMethod_New(self, obj);
+}
+
+static PyObject *
 lru_cache_cache_info(lru_cache_object *self, PyObject *unused)
 {
     return PyObject_CallFunction(self->cache_info_type, "nnOn",
@@ -1115,7 +1125,7 @@
     lru_cache_getsetlist,               /* tp_getset */
     0,                                  /* tp_base */
     0,                                  /* tp_dict */
-    0,                                  /* tp_descr_get */
+    lru_cache_descr_get,                /* tp_descr_get */
     0,                                  /* tp_descr_set */
     offsetof(lru_cache_object, dict),   /* tp_dictoffset */
     0,                                  /* tp_init */