bpo-39573: Add Py_IS_TYPE() function (GH-18488)

Co-Author: Neil Schemenauer <nas-github@arctrix.com>

Author: corona10

Doc/c-api/structures.rst

@@ -70,6 +70,14 @@ the definition of all other Python objects.
  (((PyObject*)(o))->ob_type)
 
 
+.. c:function:: int Py_IS_TYPE(PyObject *o, PyTypeObject *type)
+
+ Return non-zero if the object *o* type is *type*. Return zero otherwise.
+ Equivalent to: ``Py_TYPE(o) == type``.
+
+ .. versionadded:: 3.9
+
+
 .. c:function:: void Py_SET_TYPE(PyObject *o, PyTypeObject *type)
 
  Set the object *o* type to *type*.

Include/boolobject.h

@@ -9,7 +9,7 @@ extern "C" {
 
 PyAPI_DATA(PyTypeObject) PyBool_Type;
 
-#define PyBool_Check(x) (Py_TYPE(x) == &PyBool_Type)
+#define PyBool_Check(x) Py_IS_TYPE(x, &PyBool_Type)
 
 /* Py_False and Py_True are the only two bools in existence.
 Don't forget to apply Py_INCREF() when returning either!!! */

Include/bytearrayobject.h

@@ -24,7 +24,7 @@ PyAPI_DATA(PyTypeObject) PyByteArrayIter_Type;
 
 /* Type check macros */
 #define PyByteArray_Check(self) PyObject_TypeCheck(self, &PyByteArray_Type)
-#define PyByteArray_CheckExact(self) (Py_TYPE(self) == &PyByteArray_Type)
+#define PyByteArray_CheckExact(self) Py_IS_TYPE(self, &PyByteArray_Type)
 
 /* Direct API functions */
 PyAPI_FUNC(PyObject *) PyByteArray_FromObject(PyObject *);

Include/bytesobject.h

@@ -32,7 +32,7 @@ PyAPI_DATA(PyTypeObject) PyBytesIter_Type;
 
 #define PyBytes_Check(op) \
  PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_BYTES_SUBCLASS)
-#define PyBytes_CheckExact(op) (Py_TYPE(op) == &PyBytes_Type)
+#define PyBytes_CheckExact(op) Py_IS_TYPE(op, &PyBytes_Type)
 
 PyAPI_FUNC(PyObject *) PyBytes_FromStringAndSize(const char *, Py_ssize_t);
 PyAPI_FUNC(PyObject *) PyBytes_FromString(const char *);

Include/cellobject.h

@@ -13,7 +13,7 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyCell_Type;
 
-#define PyCell_Check(op) (Py_TYPE(op) == &PyCell_Type)
+#define PyCell_Check(op) Py_IS_TYPE(op, &PyCell_Type)
 
 PyAPI_FUNC(PyObject *) PyCell_New(PyObject *);
 PyAPI_FUNC(PyObject *) PyCell_Get(PyObject *);

Include/code.h

@@ -115,7 +115,7 @@ typedef struct {
 
 PyAPI_DATA(PyTypeObject) PyCode_Type;
 
-#define PyCode_Check(op) (Py_TYPE(op) == &PyCode_Type)
+#define PyCode_Check(op) Py_IS_TYPE(op, &PyCode_Type)
 #define PyCode_GetNumFree(op) (PyTuple_GET_SIZE((op)->co_freevars))
 
 /* Public interface */

Include/complexobject.h

@@ -39,7 +39,7 @@ typedef struct {
 PyAPI_DATA(PyTypeObject) PyComplex_Type;
 
 #define PyComplex_Check(op) PyObject_TypeCheck(op, &PyComplex_Type)
-#define PyComplex_CheckExact(op) (Py_TYPE(op) == &PyComplex_Type)
+#define PyComplex_CheckExact(op) Py_IS_TYPE(op, &PyComplex_Type)
 
 #ifndef Py_LIMITED_API
 PyAPI_FUNC(PyObject *) PyComplex_FromCComplex(Py_complex);

Include/context.h

@@ -17,9 +17,9 @@ PyAPI_DATA(PyTypeObject) PyContextToken_Type;
 typedef struct _pycontexttokenobject PyContextToken;
 
 
-#define PyContext_CheckExact(o) (Py_TYPE(o) == &PyContext_Type)
-#define PyContextVar_CheckExact(o) (Py_TYPE(o) == &PyContextVar_Type)
-#define PyContextToken_CheckExact(o) (Py_TYPE(o) == &PyContextToken_Type)
+#define PyContext_CheckExact(o) Py_IS_TYPE(o, &PyContext_Type)
+#define PyContextVar_CheckExact(o) Py_IS_TYPE(o, &PyContextVar_Type)
+#define PyContextToken_CheckExact(o) Py_IS_TYPE(o, &PyContextToken_Type)
 
 
 PyAPI_FUNC(PyObject *) PyContext_New(void);

Include/datetime.h

@@ -196,19 +196,19 @@ static PyDateTime_CAPI *PyDateTimeAPI = NULL;
 
 /* Macros for type checking when not building the Python core. */
 #define PyDate_Check(op) PyObject_TypeCheck(op, PyDateTimeAPI->DateType)
-#define PyDate_CheckExact(op) (Py_TYPE(op) == PyDateTimeAPI->DateType)
+#define PyDate_CheckExact(op) Py_IS_TYPE(op, PyDateTimeAPI->DateType)
 
 #define PyDateTime_Check(op) PyObject_TypeCheck(op, PyDateTimeAPI->DateTimeType)
-#define PyDateTime_CheckExact(op) (Py_TYPE(op) == PyDateTimeAPI->DateTimeType)
+#define PyDateTime_CheckExact(op) Py_IS_TYPE(op, PyDateTimeAPI->DateTimeType)
 
 #define PyTime_Check(op) PyObject_TypeCheck(op, PyDateTimeAPI->TimeType)
-#define PyTime_CheckExact(op) (Py_TYPE(op) == PyDateTimeAPI->TimeType)
+#define PyTime_CheckExact(op) Py_IS_TYPE(op, PyDateTimeAPI->TimeType)
 
 #define PyDelta_Check(op) PyObject_TypeCheck(op, PyDateTimeAPI->DeltaType)
-#define PyDelta_CheckExact(op) (Py_TYPE(op) == PyDateTimeAPI->DeltaType)
+#define PyDelta_CheckExact(op) Py_IS_TYPE(op, PyDateTimeAPI->DeltaType)
 
 #define PyTZInfo_Check(op) PyObject_TypeCheck(op, PyDateTimeAPI->TZInfoType)
-#define PyTZInfo_CheckExact(op) (Py_TYPE(op) == PyDateTimeAPI->TZInfoType)
+#define PyTZInfo_CheckExact(op) Py_IS_TYPE(op, PyDateTimeAPI->TZInfoType)
 
 
 /* Macros for accessing constructors in a simplified fashion. */

Include/dictobject.h

@@ -16,7 +16,7 @@ PyAPI_DATA(PyTypeObject) PyDict_Type;
 
 #define PyDict_Check(op) \
  PyType_FastSubclass(Py_TYPE(op), Py_TPFLAGS_DICT_SUBCLASS)
-#define PyDict_CheckExact(op) (Py_TYPE(op) == &PyDict_Type)
+#define PyDict_CheckExact(op) Py_IS_TYPE(op, &PyDict_Type)
 
 PyAPI_FUNC(PyObject *) PyDict_New(void);
 PyAPI_FUNC(PyObject *) PyDict_GetItem(PyObject *mp, PyObject *key);