From 4e1c22779e95a9c86c70640309482b4f5113a4d1 Mon Sep 17 00:00:00 2001
From: Brad Warren <bmw@users.noreply.github.com>
Date: Mon, 19 Nov 2018 11:47:14 -0800
Subject: [PATCH] Fix up environment variable use in venv creation scripts
 (#6518)

This PR has the value of VENV_NAME override any value set in the tools/venv* scripts.

I also removed the use of VENV_ARGS. This was used in _venv_common.sh as a means of passing arguments for virtualenv between the scripts, however, there is no other use of the variable in this repository and passing the arguments through a function call is much more natural in Python.

* Respect VENV_NAME in tools/venv*.

* Stop using VENV_ARGS

* Remove VENV_NAME_ENV_VAR and add docstrings.
---
 tools/_venv_common.py | 29 +++++++++++++++++++++++++++--
 1 file changed, 27 insertions(+), 2 deletions(-)

diff --git a/tools/_venv_common.py b/tools/_venv_common.py
index c44d05bf7..bddda6302 100755
--- a/tools/_venv_common.py
+++ b/tools/_venv_common.py
@@ -1,4 +1,14 @@
 #!/usr/bin/env python
+"""Aids in creating a developer virtual environment for Certbot.
+
+When this module is run as a script, it takes the arguments that should
+be passed to pip to install the Certbot packages as command line
+arguments. The virtual environment will be created with the name "venv"
+in the current working directory and will use the default version of
+Python for the virtualenv executable in your PATH. You can change the
+name of the virtual environment by setting the environment variable
+VENV_NAME.
+"""
 
 from __future__ import print_function
 
@@ -110,12 +120,27 @@ def get_venv_python(venv_path):
 
 
 def main(venv_name, venv_args, args):
+    """Creates a virtual environment and installs packages.
+
+    :param str venv_name: The name or path at where the virtual
+        environment should be created.
+    :param str venv_args: Command line arguments for virtualenv
+    :param str args: Command line arguments that should be given to pip
+        to install packages
+    """
+
     for path in glob.glob('*.egg-info'):
         if os.path.isdir(path):
             shutil.rmtree(path)
         else:
             os.remove(path)
 
+    env_venv_name = os.environ.get('VENV_NAME')
+    if env_venv_name:
+        print('Creating venv at {0}'
+              ' as specified in VENV_NAME'.format(env_venv_name))
+        venv_name = env_venv_name
+
     if os.path.isdir(venv_name):
         os.rename(venv_name, '{0}.{1}.bak'.format(venv_name, int(time.time())))
 
@@ -150,6 +175,6 @@ def main(venv_name, venv_args, args):
 
 
 if __name__ == '__main__':
-    main(os.environ.get('VENV_NAME', 'venv'),
-         os.environ.get('VENV_ARGS', ''),
+    main('venv',
+         '',
          sys.argv[1:])