Yet, Greg’s point is that this only works if the developer tests their code
with the new Python version.

I’m not sure that his proposal is better though. I think static checkers
are the better remedy.

On Sun, Sep 30, 2018 at 10:02 AM Serhiy Storchaka <report@bugs.python.org>
wrote:

>
> Serhiy Storchaka <storchaka+cpython@gmail.com> added the comment:
>
> There is a large difference with the DeprecationWarning in the md5 and sha
> modules.
>
> A SyntaxWarning is emitted when the compiler compiles Python sources to
> bytecode. Since bytecode is cached in pyc files, you will see it at most
> once at first run of the application. If the application compiles Python
> files at install time, warnings will be emitted at that time, and will be
> not emitted when run the application. If the application is distributed
> with precompiled pyc files, the user will not see warnings at all. If the
> developer installs dependencies that contain this error, his will see a
> warning only once, and can either ignore it (taking the current state), or
> report a bug. Warnings will not annoy him when he debug his code.
>
> In contrary, the DeprecationWarning was emitted every time when you import
> the md5 or sha modules.
>
> Professional applications likely already use checkers which caught this
> error. This warning will help non-professional applications distributed as
> a single script or handful of scripts. Users of such application often seat
> near its author. In many cases the only user is its author.
>
> ----------
>
> _______________________________________
> Python tracker <report@bugs.python.org>
> <https://bugs.python.org/issue34850>
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