pythongh-112205: Support @setter annotation from AC (pythongh-112922)

---------

Co-authored-by: Erlend E. Aasland <erlend.aasland@protonmail.com>
Co-authored-by: Alex Waygood <Alex.Waygood@Gmail.com>

Lib/test/clinic.test.c

@@ -4956,8 +4956,12 @@ Test_meth_coexist_impl(TestObj *self)
 Test.property
 [clinic start generated code]*/
 
-#define TEST_PROPERTY_GETTERDEF    \
-    {"property", (getter)Test_property_get, NULL, NULL},
+#if defined(TEST_PROPERTY_GETSETDEF)
+#  undef TEST_PROPERTY_GETSETDEF
+#  define TEST_PROPERTY_GETSETDEF {"property", (getter)Test_property_get, (setter)Test_property_set, NULL},
+#else
+#  define TEST_PROPERTY_GETSETDEF {"property", (getter)Test_property_get, NULL, NULL},
+#endif
 
 static PyObject *
 Test_property_get_impl(TestObj *self);
@@ -4970,8 +4974,32 @@ Test_property_get(TestObj *self, void *Py_UNUSED(context))
 
 static PyObject *
 Test_property_get_impl(TestObj *self)
-/*[clinic end generated code: output=892b6fb351ff85fd input=2d92b3449fbc7d2b]*/
+/*[clinic end generated code: output=af8140b692e0e2f1 input=2d92b3449fbc7d2b]*/
+
+/*[clinic input]
+@setter
+Test.property
+[clinic start generated code]*/
+
+#if defined(TEST_PROPERTY_GETSETDEF)
+#  undef TEST_PROPERTY_GETSETDEF
+#  define TEST_PROPERTY_GETSETDEF {"property", (getter)Test_property_get, (setter)Test_property_set, NULL},
+#else
+#  define TEST_PROPERTY_GETSETDEF {"property", NULL, (setter)Test_property_set, NULL},
+#endif
+
+static int
+Test_property_set_impl(TestObj *self, PyObject *value);
+
+static int
+Test_property_set(TestObj *self, PyObject *value, void *Py_UNUSED(context))
+{
+    return Test_property_set_impl(self, value);
+}
 
+static int
+Test_property_set_impl(TestObj *self, PyObject *value)
+/*[clinic end generated code: output=f3eba6487d7550e2 input=3bc3f46a23c83a88]*/
 
 /*[clinic input]
 output push

Lib/test/test_clinic.py

@@ -2197,6 +2197,58 @@ class Foo "" ""
                 expected_error = err_template.format(invalid_kind)
                 self.expect_failure(block, expected_error, lineno=3)
 
+    def test_invalid_getset(self):
+        annotations = ["@getter", "@setter"]
+        for annotation in annotations:
+            with self.subTest(annotation=annotation):
+                block = f"""
+                    module foo
+                    class Foo "" ""
+                    {annotation}
+                    Foo.property -> int
+                """
+                expected_error = f"{annotation} method cannot define a return type"
+                self.expect_failure(block, expected_error, lineno=3)
+
+                block = f"""
+                   module foo
+                   class Foo "" ""
+                   {annotation}
+                   Foo.property
+                       obj: int
+                       /
+                """
+                expected_error = f"{annotation} method cannot define parameters"
+                self.expect_failure(block, expected_error)
+
+    def test_duplicate_getset(self):
+        annotations = ["@getter", "@setter"]
+        for annotation in annotations:
+            with self.subTest(annotation=annotation):
+                block = f"""
+                    module foo
+                    class Foo "" ""
+                    {annotation}
+                    {annotation}
+                    Foo.property -> int
+                """
+                expected_error = f"Cannot apply {annotation} twice to the same function!"
+                self.expect_failure(block, expected_error, lineno=3)
+
+    def test_getter_and_setter_disallowed_on_same_function(self):
+        dup_annotations = [("@getter", "@setter"), ("@setter", "@getter")]
+        for dup in dup_annotations:
+            with self.subTest(dup=dup):
+                block = f"""
+                    module foo
+                    class Foo "" ""
+                    {dup[0]}
+                    {dup[1]}
+                    Foo.property -> int
+                """
+                expected_error = "Cannot apply both @getter and @setter to the same function!"
+                self.expect_failure(block, expected_error, lineno=3)
+
     def test_duplicate_coexist(self):
         err = "Called @coexist twice"
         block = """

Modules/_io/bufferedio.c

@@ -2526,9 +2526,9 @@ static PyMemberDef bufferedreader_members[] = {
 };
 
 static PyGetSetDef bufferedreader_getset[] = {
-    _IO__BUFFERED_CLOSED_GETTERDEF
-    _IO__BUFFERED_NAME_GETTERDEF
-    _IO__BUFFERED_MODE_GETTERDEF
+    _IO__BUFFERED_CLOSED_GETSETDEF
+    _IO__BUFFERED_NAME_GETSETDEF
+    _IO__BUFFERED_MODE_GETSETDEF
     {NULL}
 };
 
@@ -2586,9 +2586,9 @@ static PyMemberDef bufferedwriter_members[] = {
 };
 
 static PyGetSetDef bufferedwriter_getset[] = {
-    _IO__BUFFERED_CLOSED_GETTERDEF
-    _IO__BUFFERED_NAME_GETTERDEF
-    _IO__BUFFERED_MODE_GETTERDEF
+    _IO__BUFFERED_CLOSED_GETSETDEF
+    _IO__BUFFERED_NAME_GETSETDEF
+    _IO__BUFFERED_MODE_GETSETDEF
     {NULL}
 };
 
@@ -2704,9 +2704,9 @@ static PyMemberDef bufferedrandom_members[] = {
 };
 
 static PyGetSetDef bufferedrandom_getset[] = {
-    _IO__BUFFERED_CLOSED_GETTERDEF
-    _IO__BUFFERED_NAME_GETTERDEF
-    _IO__BUFFERED_MODE_GETTERDEF
+    _IO__BUFFERED_CLOSED_GETSETDEF
+    _IO__BUFFERED_NAME_GETSETDEF
+    _IO__BUFFERED_MODE_GETSETDEF
     {NULL}
 };
 

Modules/_io/stringio.c

@@ -1037,15 +1037,15 @@ static struct PyMethodDef stringio_methods[] = {
 };
 
 static PyGetSetDef stringio_getset[] = {
-    _IO_STRINGIO_CLOSED_GETTERDEF
-    _IO_STRINGIO_NEWLINES_GETTERDEF
+    _IO_STRINGIO_CLOSED_GETSETDEF
+    _IO_STRINGIO_NEWLINES_GETSETDEF
     /*  (following comments straight off of the original Python wrapper:)
         XXX Cruft to support the TextIOWrapper API. This would only
         be meaningful if StringIO supported the buffer attribute.
         Hopefully, a better solution, than adding these pseudo-attributes,
         will be found.
     */
-    _IO_STRINGIO_LINE_BUFFERING_GETTERDEF
+    _IO_STRINGIO_LINE_BUFFERING_GETSETDEF
     {NULL}
 };
 

Modules/_io/textio.c

@@ -3238,33 +3238,37 @@ textiowrapper_errors_get(textio *self, void *context)
     return result;
 }
 
+/*[clinic input]
+@critical_section
+@getter
+_io.TextIOWrapper._CHUNK_SIZE
+[clinic start generated code]*/
+
 static PyObject *
-textiowrapper_chunk_size_get_impl(textio *self, void *context)
+_io_TextIOWrapper__CHUNK_SIZE_get_impl(textio *self)
+/*[clinic end generated code: output=039925cd2df375bc input=e9715b0e06ff0fa6]*/
 {
     CHECK_ATTACHED(self);
     return PyLong_FromSsize_t(self->chunk_size);
 }
 
-static PyObject *
-textiowrapper_chunk_size_get(textio *self, void *context)
-{
-    PyObject *result = NULL;
-    Py_BEGIN_CRITICAL_SECTION(self);
-    result = textiowrapper_chunk_size_get_impl(self, context);
-    Py_END_CRITICAL_SECTION();
-    return result;
-}
+/*[clinic input]
+@critical_section
+@setter
+_io.TextIOWrapper._CHUNK_SIZE
+[clinic start generated code]*/
 
 static int
-textiowrapper_chunk_size_set_impl(textio *self, PyObject *arg, void *context)
+_io_TextIOWrapper__CHUNK_SIZE_set_impl(textio *self, PyObject *value)
+/*[clinic end generated code: output=edb86d2db660a5ab input=32fc99861db02a0a]*/
 {
     Py_ssize_t n;
     CHECK_ATTACHED_INT(self);
-    if (arg == NULL) {
+    if (value == NULL) {
         PyErr_SetString(PyExc_AttributeError, "cannot delete attribute");
         return -1;
     }
-    n = PyNumber_AsSsize_t(arg, PyExc_ValueError);
+    n = PyNumber_AsSsize_t(value, PyExc_ValueError);
     if (n == -1 && PyErr_Occurred())
         return -1;
     if (n <= 0) {
@@ -3276,16 +3280,6 @@ textiowrapper_chunk_size_set_impl(textio *self, PyObject *arg, void *context)
     return 0;
 }
 
-static int
-textiowrapper_chunk_size_set(textio *self, PyObject *arg, void *context)
-{
-    int result = 0;
-    Py_BEGIN_CRITICAL_SECTION(self);
-    result = textiowrapper_chunk_size_set_impl(self, arg, context);
-    Py_END_CRITICAL_SECTION();
-    return result;
-}
-
 static PyMethodDef incrementalnewlinedecoder_methods[] = {
     _IO_INCREMENTALNEWLINEDECODER_DECODE_METHODDEF
     _IO_INCREMENTALNEWLINEDECODER_GETSTATE_METHODDEF
@@ -3361,8 +3355,7 @@ static PyGetSetDef textiowrapper_getset[] = {
 */
     {"newlines", (getter)textiowrapper_newlines_get, NULL, NULL},
     {"errors", (getter)textiowrapper_errors_get, NULL, NULL},
-    {"_CHUNK_SIZE", (getter)textiowrapper_chunk_size_get,
-                    (setter)textiowrapper_chunk_size_set, NULL},
+    _IO_TEXTIOWRAPPER__CHUNK_SIZE_GETSETDEF
     {NULL}
 };