Subclassing Sounds + Channels.

buildconfig/stubs/pygame/mixer.pyi

@@ -1,4 +1,4 @@
-from typing import Any, Dict, Optional, Tuple, Union, final, overload
+from typing import Any, Dict, Optional, Tuple, Union, overload
 
 import numpy
 
@@ -70,7 +70,7 @@ class Sound:
     def get_length(self) -> float: ...
     def get_raw(self) -> bytes: ...
 
-@final
+
 class Channel:
     def __init__(self, id: int) -> None: ...
     @property

docs/reST/ref/mixer.rst

@@ -460,6 +460,7 @@ change the default buffer by calling :func:`pygame.mixer.pre_init` before
 
    .. versionchanged:: 2.1.4 This class is also available through the ``pygame.Channel``
       alias.
+   .. versionchanged:: 2.4.0 It is now possible to create subclasses of ``pygame.mixer.Channel``
 
    .. attribute:: id
 

src_c/include/pygame_mixer.h

@@ -50,8 +50,7 @@ typedef struct {
 PYGAMEAPI_DEFINE_SLOTS(mixer);
 
 #define pgSound_Type (*(PyTypeObject *)PYGAMEAPI_GET_SLOT(mixer, 0))
-
-#define pgSound_Check(x) ((x)->ob_type == &pgSound_Type)
+#define pgSound_Check(x) (PyObject_IsInstance(x, (PyObject *)&pgSound_Type))
 
 #define pgSound_New \
     (*(PyObject * (*)(Mix_Chunk *)) PYGAMEAPI_GET_SLOT(mixer, 1))
@@ -60,7 +59,8 @@ PYGAMEAPI_DEFINE_SLOTS(mixer);
     (*(PyObject * (*)(PyObject *, PyObject *)) PYGAMEAPI_GET_SLOT(mixer, 2))
 
 #define pgChannel_Type (*(PyTypeObject *)PYGAMEAPI_GET_SLOT(mixer, 3))
-#define pgChannel_Check(x) ((x)->ob_type == &pgChannel_Type)
+#define pgChannel_Check(x) \
+    (PyObject_IsInstance(x, (PyObject *)&pgChannel_Type))
 
 #define pgChannel_New (*(PyObject * (*)(int)) PYGAMEAPI_GET_SLOT(mixer, 4))
 

src_c/mixer.c

@@ -85,8 +85,9 @@ static PyObject *
 pgSound_New(Mix_Chunk *);
 static PyObject *
 pgChannel_New(int);
-#define pgSound_Check(x) (Py_TYPE(x) == &pgSound_Type)
-#define pgChannel_Check(x) (Py_TYPE(x) == &pgChannel_Type)
+#define pgSound_Check(x) (PyObject_IsInstance(x, (PyObject *)&pgSound_Type))
+#define pgChannel_Check(x) \
+    (PyObject_IsInstance(x, (PyObject *)&pgChannel_Type))
 
 static int
 snd_getbuffer(PyObject *, Py_buffer *, int);
@@ -1373,6 +1374,7 @@ static PyTypeObject pgChannel_Type = {
     PyVarObject_HEAD_INIT(NULL, 0).tp_name = "pygame.mixer.Channel",
     .tp_basicsize = sizeof(pgChannelObject),
     .tp_dealloc = channel_dealloc,
+    .tp_flags = (Py_TPFLAGS_DEFAULT | Py_TPFLAGS_BASETYPE),
     .tp_doc = DOC_MIXER_CHANNEL,
     .tp_methods = channel_methods,
     .tp_init = (initproc)channel_init,

test/mixer_test.py

@@ -934,6 +934,10 @@ def test_id_getter(self):
         self.assertEqual(ch1.id, 1)
         self.assertEqual(ch2.id, 2)
 
+    def test_subclass(self):
+        class MyChannel(mixer.Channel):
+            pass
+
 
 class ChannelInteractiveTest(unittest.TestCase):
     __tags__ = ["interactive"]
@@ -1264,6 +1268,17 @@ def __init__(self, file):
         except Exception:
             self.fail("This should not raise an exception.")
 
+        channel = mixer.Channel(0)
+        try:
+            channel.play(correct)
+        except Exception:
+            self.fail("This should not raise an exception.")
+
+        self.assertIsInstance(channel.get_sound(), CorrectSublass)
+        self.assertIs(channel.get_sound(), correct)
+
+        channel.stop()
+
     def test_incorrect_subclassing(self):
         class IncorrectSuclass(mixer.Sound):
             def __init__(self):