From e568adc41ca71a46d9240e88dc97ca8a9fed169a Mon Sep 17 00:00:00 2001
From: Wolfgang Maier <wolfgang.maier@biologie.uni-freiburg.de>
Date: Mon, 30 May 2016 11:33:25 +0200
Subject: [PATCH] consider root path when looking for installed versions

---
 pip/commands/install.py | 1 +
 1 file changed, 1 insertion(+)

diff --git a/pip/commands/install.py b/pip/commands/install.py
index b9bf5ba56ee..b63361090c5 100644
--- a/pip/commands/install.py
+++ b/pip/commands/install.py
@@ -320,6 +320,7 @@ def run(self, options, args):
                         possible_lib_locations = get_lib_location_guesses(
                             user=options.use_user_site,
                             home=temp_target_dir,
+                            root=options.root_path,
                             prefix=options.prefix_path,
                             isolated=options.isolated_mode,
                         )