On Fri, Mar 22, 2019 at 6:19 PM Inada Naoki <songofacandy@gmail.com> wrote:
On Sat, Mar 23, 2019 at 3:02 AM Brett Cannon <brett@python.org> wrote:
>
>>
>> There might be some small troubles.  But it was small enough for
>> Python minor versions, I think.
>
>
>  I don't think it's worth the cost to users. We can just choose to stop using it in the stdlib and not use PendingDeprecationWarning. And if people want to force others to define their own PendingDeprecationWarning by deprecating that's fine, but the aliasing where it could cause unintended exception swallowing for something related to breaking changes seems unnecessarily risky to me simply because we don't want to ask users to update their code in a backwards-compatible fashion.

I still can't believe there are real world usage of PendingDeprecationWarning
other than warnings.warn() and assertRaises().

I've made the same mistake of assuming something that made no sense to me wouldn't make sense to anyone else and I have been proven wrong nearly every time. ;)

-Brett
 

But I'm OK to not removing actual class.

Stop using it in stdlib reduces maintenance cost like this:
https://github.com/python/cpython/pull/12494/files

And deprecation in document reduces learning cost.
People can skip reading and understanding document of PendingDeprecatedWarning.

Keeping PendingDeprecationWarning class for several years is very
low cost compared to these cost.

Regards,
--
Inada Naoki  <songofacandy@gmail.com>