Add unit tests for credentials lookup

6 jobs for single_client in 3 minutes and 34 seconds (queued for 5 seconds)
Status Job ID Name Coverage
  Build
passed #219012
build:debian:jessie

00:03:14

passed #219013
build:debian:stretch

00:01:11

passed #219011
build:el7

00:00:54

passed #219010
build:tarball

00:00:19

 
  Test
passed #219014
test:python2.7

00:00:17

passed #219015
test:python3.6

00:00:18