Make dict.keys() and dict.items() comparable to sets, using == and !=.
(PEP 3106 requires subset comparisons too, those will come later if someone
really wants them. :-)
diff --git a/Objects/dictobject.c b/Objects/dictobject.c
index 49907b4..eeb8bd5 100644
--- a/Objects/dictobject.c
+++ b/Objects/dictobject.c
@@ -2399,6 +2399,83 @@
return (PyObject *)dv;
}
+/* Forward */
+PyTypeObject PyDictKeys_Type;
+PyTypeObject PyDictItems_Type;
+PyTypeObject PyDictValues_Type;
+
+#define PyDictKeys_Check(obj) ((obj)->ob_type == &PyDictKeys_Type)
+#define PyDictItems_Check(obj) ((obj)->ob_type == &PyDictItems_Type)
+#define PyDictValues_Check(obj) ((obj)->ob_type == &PyDictValues_Type)
+
+/* This excludes Values, since they are not sets. */
+# define PyDictViewSet_Check(obj) \
+ (PyDictKeys_Check(obj) || PyDictItems_Check(obj))
+
+static int
+all_contained_in(PyObject *self, PyObject *other)
+{
+ PyObject *iter = PyObject_GetIter(self);
+ int ok = 1;
+
+ if (iter == NULL)
+ return -1;
+ for (;;) {
+ PyObject *next = PyIter_Next(iter);
+ if (next == NULL) {
+ if (PyErr_Occurred())
+ ok = -1;
+ break;
+ }
+ ok = PySequence_Contains(other, next);
+ Py_DECREF(next);
+ if (ok <= 0)
+ break;
+ }
+ Py_DECREF(iter);
+ return ok;
+}
+
+static PyObject *
+dictview_richcompare(PyObject *self, PyObject *other, int op)
+{
+ assert(self != NULL);
+ assert(PyDictViewSet_Check(self));
+ assert(other != NULL);
+ if ((op == Py_EQ || op == Py_NE) &&
+ (PyAnySet_Check(other) || PyDictViewSet_Check(other)))
+ {
+ Py_ssize_t len_self, len_other;
+ int ok;
+ PyObject *result;
+
+ len_self = PyObject_Size(self);
+ if (len_self < 0)
+ return NULL;
+ len_other = PyObject_Size(other);
+ if (len_other < 0)
+ return NULL;
+ if (len_self != len_other)
+ ok = 0;
+ else if (len_self == 0)
+ ok = 1;
+ else
+ ok = all_contained_in(self, other);
+ if (ok < 0)
+ return NULL;
+ if (ok == (op == Py_EQ))
+ result = Py_True;
+ else
+ result = Py_False;
+ Py_INCREF(result);
+ return result;
+ }
+ else {
+ Py_INCREF(Py_NotImplemented);
+ return Py_NotImplemented;
+ }
+}
+
/*** dict_keys ***/
static PyObject *
@@ -2459,7 +2536,7 @@
0, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
- 0, /* tp_richcompare */
+ dictview_richcompare, /* tp_richcompare */
0, /* tp_weaklistoffset */
(getiterfunc)dictkeys_iter, /* tp_iter */
0, /* tp_iternext */
@@ -2544,7 +2621,7 @@
0, /* tp_doc */
0, /* tp_traverse */
0, /* tp_clear */
- 0, /* tp_richcompare */
+ dictview_richcompare, /* tp_richcompare */
0, /* tp_weaklistoffset */
(getiterfunc)dictitems_iter, /* tp_iter */
0, /* tp_iternext */