[issue24875] pyvenv doesn´t install PIP inside a new venv with --system-site-package

[Nicolas Demarchi]

New submission from Nicolas Demarchi:

When Envbuilder creates a new virtualenv with system_site_packages=True,
in the process of installing pip itself it actually doesn't install it inside the virtualenv because it is already there in the system.

However when you do it manually using "virtualenv" it does install pip inside the virtualenv as you would expect to.


```
(22d667c6-e383-47be-9785-ec044008b654)  ~/.local/share/fades/22d667c6-e383-47be-9785-ec044008b654  pwd
/home/gilgamezh/.local/share/fades/22d667c6-e383-47be-9785-ec044008b654
(22d667c6-e383-47be-9785-ec044008b654)  ~/.local/share/fades/22d667c6-e383-47be-9785-ec044008b654  ll
total 16
drwxr-xr-x 2 gilgamezh users 4096 Aug 16 00:05 bin
drwxr-xr-x 2 gilgamezh users 4096 Aug 16 00:05 include
drwxr-xr-x 3 gilgamezh users 4096 Aug 16 00:05 lib
lrwxrwxrwx 1 gilgamezh users    3 Aug 16 00:05 lib64 -> lib
-rw-r--r-- 1 gilgamezh users   68 Aug 16 00:05 pyvenv.cfg
(22d667c6-e383-47be-9785-ec044008b654)  ~/.local/share/fades/22d667c6-e383-47be-9785-ec044008b654  ll bin 
total 12
-rw-r--r-- 1 gilgamezh users 2251 Aug 16 00:05 activate
-rw-r--r-- 1 gilgamezh users 1367 Aug 16 00:05 activate.csh
-rw-r--r-- 1 gilgamezh users 2503 Aug 16 00:05 activate.fish
lrwxrwxrwx 1 gilgamezh users    7 Aug 16 00:05 python -> python3
lrwxrwxrwx 1 gilgamezh users   16 Aug 16 00:05 python3 -> /usr/bin/python3
(22d667c6-e383-47be-9785-ec044008b654)  ~/.local/share/fades/22d667c6-e383-47be-9785-ec044008b654  bin/python -Im ensurepip --upgrade --default-pip -v 
Ignoring indexes: https://pypi.python.org/simple
URLs to search for versions for setuptools in /usr/lib/python3.4/site-packages:
Skipping link /tmp/tmpe8rbjkcq (from -f); not a file
Skipping link file:///tmp/tmpe8rbjkcq/pip-6.0.8-py2.py3-none-any.whl; wrong project name (not setuptools)
Found link file:///tmp/tmpe8rbjkcq/setuptools-12.0.5-py2.py3-none-any.whl, version: 12.0.5
Local files found: /tmp/tmpe8rbjkcq/setuptools-12.0.5-py2.py3-none-any.whl
Installed version (18.1) is most up-to-date (past versions: 12.0.5)
Requirement already up-to-date: setuptools in /usr/lib/python3.4/site-packages
URLs to search for versions for pip in /usr/lib/python3.4/site-packages:
Found link file:///tmp/tmpe8rbjkcq/pip-6.0.8-py2.py3-none-any.whl, version: 6.0.8
Skipping link file:///tmp/tmpe8rbjkcq/setuptools-12.0.5-py2.py3-none-any.whl; wrong project name (not pip)
Local files found: /tmp/tmpe8rbjkcq/pip-6.0.8-py2.py3-none-any.whl
Installed version (7.1.0) is most up-to-date (past versions: 6.0.8)
Requirement already up-to-date: pip in /usr/lib/python3.4/site-packages
Cleaning up...
(22d667c6-e383-47be-9785-ec044008b654)  ~/.local/share/fades/22d667c6-e383-47be-9785-ec044008b654  
```

"bin/python -Im ensurepip --upgrade --default-pip -v" is from /usr/lib/python3.4/venv/__init__.py line 255

----------
components: Library (Lib)
messages: 248673
nosy: gilgamezh
priority: normal
severity: normal
status: open
title: pyvenv doesn´t install PIP inside a new venv with --system-site-package
type: behavior
versions: Python 3.4

_______________________________________
Python tracker <report at bugs.python.org>
<http://bugs.python.org/issue24875>
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