bpo-43908: Make array.array type immutable (GH-25696)
Co-authored-by: Victor Stinner <vstinner@python.org>
diff --git a/Lib/test/test_array.py b/Lib/test/test_array.py
index bdcd125..11184ad 100644
--- a/Lib/test/test_array.py
+++ b/Lib/test/test_array.py
@@ -40,6 +40,12 @@ def test_bad_constructor(self):
self.assertRaises(TypeError, array.array, 'xx')
self.assertRaises(ValueError, array.array, 'x')
+ @support.cpython_only
+ def test_immutable(self):
+ # bpo-43908: check that array.array is immutable
+ with self.assertRaises(TypeError):
+ array.array.foo = 1
+
def test_empty(self):
# Exercise code for handling zero-length arrays
a = array.array('B')
diff --git a/Misc/NEWS.d/next/Core and Builtins/2021-04-26-20-59-17.bpo-43908.-COW4-.rst b/Misc/NEWS.d/next/Core and Builtins/2021-04-26-20-59-17.bpo-43908.-COW4-.rst
new file mode 100644
index 0000000..07303b9
--- /dev/null
+++ b/Misc/NEWS.d/next/Core and Builtins/2021-04-26-20-59-17.bpo-43908.-COW4-.rst
@@ -0,0 +1,2 @@
+Make the :class:`array.array` type immutable. Patch by
+Erlend E. Aasland.
diff --git a/Modules/arraymodule.c b/Modules/arraymodule.c
index f532678..367621f 100644
--- a/Modules/arraymodule.c
+++ b/Modules/arraymodule.c
@@ -2847,7 +2847,8 @@ static PyType_Slot array_slots[] = {
static PyType_Spec array_spec = {
.name = "array.array",
.basicsize = sizeof(arrayobject),
- .flags = Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE,
+ .flags = (Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE |
+ Py_TPFLAGS_IMMUTABLETYPE),
.slots = array_slots,
};