[Distutils] Request for comment: Proposal to change behaviour of pip install

[Nathaniel Smith]

On Sat, Jun 25, 2016 at 9:44 PM, Nick Coghlan <ncoghlan at gmail.com> wrote:
> On 25 June 2016 at 15:40, Nathaniel Smith <njs at pobox.com> wrote:
[...]
>> - they didn't know 'foo' was installed, so they expected 'pip install
>> foo' to install it from scratch, and leave them with the latest
>> version.
>>
>> - they knew 'foo' was installed, and they (mistakenly or not) believed
>> that 'pip install' acts like 'apt-get install' and this is the way to
>> upgrade to the latest version. (Maybe they believe this because they
>> are Ubuntu users, maybe because 'pip install' is the only command they
>> know and they are making a guess, whatever),
>
> No, it's an idempotent assertion about the system state: "Make sure X
> is available, installing it if necessary".
>
> Maybe Debian folks are used to system packages stripping out the pip
> metadata, so pip has no idea what's installed, even if the system
> site-packages is configured to be visible in the venv?
>
> Python is not Linux, and it definitely isn't just Debian, so "apt does
> it that way" is not a good argument for changing behaviout that isn't
> broken.

Okay, I know how to put this more succinctly :-). I think I remember
you saying at PyCon how we need to move to a model where our defaults
are optimized for non-experts, with the expert stuff available but
non-default? My argument isn't "Debian does it this way so we should
do", my argument is "if you know what 'idempotent' means then you're
an expert".

-n

-- 
Nathaniel J. Smith -- https://vorpus.org