Apparently, else doesn't do anything without a rescue block. So just use a rescue.

lcampbell · lcampbell · commit bbff51b7f963 · 2012-05-12T06:39:11.000-05:00
diff --git a/providers/pip.rb b/providers/pip.rb
@@ -126,7 +126,7 @@ def current_installed_version
     end
     p = shell_out!(version_check_cmd)
     p.stdout.split(delimeter)[1].strip
-  else
+  rescue
   end
 end
 
