[issue21328] Resize doesn't change reported length on create_string_buffer()

[Martin Panter]

Martin Panter added the comment:

I’m not sure if resize() should change the len(). Dustin, why do you think it should? Not all ctypes objects even implement len(). The len() of 10 seems embedded in the class of the return value:

>>> b
<ctypes.c_char_Array_10 object at 0x7f143362fd90>

Also, how would this affect create_unicode_buffer(), if the buffer is resized to a non-multiple of sizeof(c_wchar)?

Gedai: I’m not that familiar with the ctypes internals, but it looks like __len__() is implemented on the Array base class:

>>> type(b).__len__
<slot wrapper '__len__' of '_ctypes.Array' objects>

Maybe look for the implementation of this method: <https://docs.python.org/3/c-api/typeobj.html#c.PySequenceMethods.sq_length>.

----------
nosy: +martin.panter

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue21328>
_______________________________________