Make PySet_Add() work with frozensets.
Works like PyTuple_SetItem() to build-up values in a brand new frozenset.
Also, PyFrozenSet_New() is now guaranteed to produce a distinct new frozenset.
diff --git a/Doc/c-api/set.rst b/Doc/c-api/set.rst
index e677c05..2ed93e9 100644
--- a/Doc/c-api/set.rst
+++ b/Doc/c-api/set.rst
@@ -86,6 +86,11 @@
set on success or *NULL* on failure. Raise :exc:`TypeError` if *iterable* is
not actually iterable.
+ .. versionchanged:: 2.6
+ Now guaranteed to return a brand-new :class:`frozenset`. Formerly,
+ frozensets of zero-length were a singleton. This got in the way of
+ building-up new frozensets with :meth:`PySet_Add`.
+
The following functions and macros are available for instances of :class:`set`
or :class:`frozenset` or instances of their subtypes.
@@ -112,9 +117,6 @@
the *key* is unhashable. Raise :exc:`PyExc_SystemError` if *anyset* is not a
:class:`set`, :class:`frozenset`, or an instance of a subtype.
-The following functions are available for instances of :class:`set` or its
-subtypes but not for instances of :class:`frozenset` or its subtypes.
-
.. cfunction:: int PySet_Add(PyObject *set, PyObject *key)
@@ -124,6 +126,14 @@
Raise a :exc:`SystemError` if *set* is an not an instance of :class:`set` or its
subtype.
+ .. versionchanged:: 2.6
+ Now works with instances of :class:`frozenset` or its subtypes.
+ Like :cfunc:`PyTuple_SetItem` in that it can be used to fill-in the
+ values of brand new frozensets before they are exposed to other code.
+
+The following functions are available for instances of :class:`set` or its
+subtypes but not for instances of :class:`frozenset` or its subtypes.
+
.. cfunction:: int PySet_Discard(PyObject *set, PyObject *key)
diff --git a/Objects/setobject.c b/Objects/setobject.c
index c8db7ce..ee11b9f 100644
--- a/Objects/setobject.c
+++ b/Objects/setobject.c
@@ -2142,17 +2142,7 @@
PyObject *
PyFrozenSet_New(PyObject *iterable)
{
- PyObject *args, *result;
-
- if (iterable == NULL)
- args = PyTuple_New(0);
- else
- args = PyTuple_Pack(1, iterable);
- if (args == NULL)
- return NULL;
- result = frozenset_new(&PyFrozenSet_Type, args, NULL);
- Py_DECREF(args);
- return result;
+ return make_new_set(&PyFrozenSet_Type, iterable);
}
Py_ssize_t
@@ -2196,13 +2186,13 @@
}
int
-PySet_Add(PyObject *set, PyObject *key)
+PySet_Add(PyObject *anyset, PyObject *key)
{
- if (!PyType_IsSubtype(Py_TYPE(set), &PySet_Type)) {
+ if (!PyAnySet_Check(anyset)) {
PyErr_BadInternalCall();
return -1;
}
- return set_add_key((PySetObject *)set, key);
+ return set_add_key((PySetObject *)anyset, key);
}
int
@@ -2345,7 +2335,6 @@
f = PyFrozenSet_New(dup);
assert(PySet_Size(f) == 3);
assert(PyFrozenSet_CheckExact(f));
- assertRaises(PySet_Add(f, elem) == -1, PyExc_SystemError);
assertRaises(PySet_Discard(f, elem) == -1, PyExc_SystemError);
assertRaises(PySet_Pop(f) == NULL, PyExc_SystemError);
Py_DECREF(f);