From 9254fbb5ffc885b89cd566199851e618804a86c7 Mon Sep 17 00:00:00 2001
From: Mohammed Naser <mnaser@vexxhost.com>
Date: Tue, 3 Mar 2020 11:55:45 -0500
Subject: [PATCH] ensure-tox: add prefer_python2

This patch enables the ability to set a value which prefers the
installation of tox within python2 over python3.

Change-Id: I29c9585aa9048c0e2855ec1eaf1f48041cfe46e2
---
 roles/ensure-tox/README.rst        | 15 +++++++++++++++
 roles/ensure-tox/defaults/main.yml |  3 ++-
 roles/ensure-tox/tasks/main.yaml   |  8 ++++++++
 3 files changed, 25 insertions(+), 1 deletion(-)

diff --git a/roles/ensure-tox/README.rst b/roles/ensure-tox/README.rst
index 60e0cac34..31a7a4a53 100644
--- a/roles/ensure-tox/README.rst
+++ b/roles/ensure-tox/README.rst
@@ -2,3 +2,18 @@ Ensure tox is installed
 
 If tox is not already installed, it will be installed via pip in the
 user install directory (i.e., "pip install --user").
+
+**Role Variables**
+
+.. zuul:rolevar:: tox_executable
+   :default: ``tox``
+
+   Optional path to point tox executable
+
+.. zuul:rolevar:: tox_prefer_python2
+   :default: ``true``
+
+   If tox is not detected, prefer to install tox inside Python 2 instead of
+   Python 3.  The default value is currently set to ``true`` for compatibility
+   reasons, it will be switched to false eventually.  It's best to set this to
+   ``false`` when using it.
diff --git a/roles/ensure-tox/defaults/main.yml b/roles/ensure-tox/defaults/main.yml
index 35e4a9af6..36efbb49a 100644
--- a/roles/ensure-tox/defaults/main.yml
+++ b/roles/ensure-tox/defaults/main.yml
@@ -1 +1,2 @@
-tox_executable: tox
\ No newline at end of file
+tox_executable: tox
+tox_prefer_python2: true
diff --git a/roles/ensure-tox/tasks/main.yaml b/roles/ensure-tox/tasks/main.yaml
index 55cd0b585..ec44cc1d6 100644
--- a/roles/ensure-tox/tasks/main.yaml
+++ b/roles/ensure-tox/tasks/main.yaml
@@ -2,11 +2,19 @@
   shell: |
     set -euo pipefail
 
+    {% if tox_prefer_python2 %}
     if command -v pip; then
       PIP=pip
     elif command -v pip3; then
       PIP=pip3
     fi
+    {% else %}
+    if command -v pip3; then
+      PIP=pip3
+    elif command -v pip; then
+      PIP=pip
+    fi
+    {% endif %}
 
     type tox || $PIP install --user tox
   args: