[Python-Dev] Deprecate PEP 370 Per user site-packages directory?

[Christian Heimes]

On 2018-01-13 19:57, Antoine Pitrou wrote:
> On Sat, 13 Jan 2018 19:18:41 +0100
> Christian Heimes <christian at python.org> wrote:
>> On 2018-01-13 19:04, Random832 wrote:
>>> On Sat, Jan 13, 2018, at 12:06, Christian Heimes wrote:  
>>>> Hi,
>>>>
>>>> PEP 370 [1] was my first PEP that got accepted. I created it exactly one
>>>> decade and two days ago for Python 2.6 and 3.0. Back then we didn't have
>>>> virtual environment support in Python. Ian Bicking had just started to
>>>> create the virtualenv project a couple of months earlier.
>>>>
>>>> Fast forward 10 years...
>>>>
>>>> Nowadays Python has venv in the standard library. The user-specific
>>>> site-packages directory is no longer that useful. I would even say it's
>>>> causing more trouble than it's worth. For example it's common for system
>>>> script to use "#!/usr/bin/python3" shebang without -s or -I option.
>>>>
>>>> I propose to deprecate the feature and remove it in Python 4.0.  
>>>
>>> Where would pip install --user put packages, and how would one run scripts that require those packages? Right now these things Just Work; I've never had to learn how to use virtual environments.  
>>
>> I see two option:
>>
>> 1) "pip install --user" is no longer supported. You have to learn how to
>> use virtual envs. It's really easy: "python3 -m venv path; path/bin/pip
>> install package".
>> 2) "pip install --user" automatically creates or uses a custom virtual
>> (~/.pip/virtualenv-$VERSION/) and links entry points to ~/.local/bin.
> 
> Option 2 doesn't work, since the installed package then isn't known to
> the system Python.

I see that as a benefit. User installed packages will no longer be able
to break system-wide programs.

These days a lot of packages are using setuptools' entry points to
create console scripts. Entry point have no option to create a console
script with -s or -I flag. On my system, only 40 out of 360 scripts in
/usr/bin have -s or -I.