bpo-42528: Improve the docs of most Py*_Check{,Exact} API calls (GH-23602)
I think that none of these API calls can fail, but only few of them are
documented as such. Add the sentence "This function always succeeds" (which is
the same already used e.g. by PyNumber_Check) to all of them.diff --git a/Doc/c-api/datetime.rst b/Doc/c-api/datetime.rst
index 415ce4c..4c4e4bc 100644
--- a/Doc/c-api/datetime.rst
+++ b/Doc/c-api/datetime.rst
@@ -28,61 +28,66 @@
.. c:function:: int PyDate_Check(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_DateType` or a subtype of
- :c:data:`PyDateTime_DateType`. *ob* must not be ``NULL``.
+ :c:data:`PyDateTime_DateType`. *ob* must not be ``NULL``. This function always
+ succeeds.
.. c:function:: int PyDate_CheckExact(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_DateType`. *ob* must not be
- ``NULL``.
+ ``NULL``. This function always succeeds.
.. c:function:: int PyDateTime_Check(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_DateTimeType` or a subtype of
- :c:data:`PyDateTime_DateTimeType`. *ob* must not be ``NULL``.
+ :c:data:`PyDateTime_DateTimeType`. *ob* must not be ``NULL``. This function always
+ succeeds.
.. c:function:: int PyDateTime_CheckExact(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_DateTimeType`. *ob* must not
- be ``NULL``.
+ be ``NULL``. This function always succeeds.
.. c:function:: int PyTime_Check(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_TimeType` or a subtype of
- :c:data:`PyDateTime_TimeType`. *ob* must not be ``NULL``.
+ :c:data:`PyDateTime_TimeType`. *ob* must not be ``NULL``. This function always
+ succeeds.
.. c:function:: int PyTime_CheckExact(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_TimeType`. *ob* must not be
- ``NULL``.
+ ``NULL``. This function always succeeds.
.. c:function:: int PyDelta_Check(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_DeltaType` or a subtype of
- :c:data:`PyDateTime_DeltaType`. *ob* must not be ``NULL``.
+ :c:data:`PyDateTime_DeltaType`. *ob* must not be ``NULL``. This function always
+ succeeds.
.. c:function:: int PyDelta_CheckExact(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_DeltaType`. *ob* must not be
- ``NULL``.
+ ``NULL``. This function always succeeds.
.. c:function:: int PyTZInfo_Check(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_TZInfoType` or a subtype of
- :c:data:`PyDateTime_TZInfoType`. *ob* must not be ``NULL``.
+ :c:data:`PyDateTime_TZInfoType`. *ob* must not be ``NULL``. This function always
+ succeeds.
.. c:function:: int PyTZInfo_CheckExact(PyObject *ob)
Return true if *ob* is of type :c:data:`PyDateTime_TZInfoType`. *ob* must not be
- ``NULL``.
+ ``NULL``. This function always succeeds.
Macros to create objects: