bug(tox): Support regular expressions via tox -e py35

This PS simply allows tox -e py35 to take in regular expressions
for better testing experience. For example:

  tox -e py35  # runs all unit tests
  tox -e py35 -- test_armada_controller  # only run unit tests that match

Change-Id: Iab5a70fa0d51e1572a31943d8f38bc9b0d6a7c18

tools/run-unit-tests.sh

@@ -0,0 +1,15 @@
+#!/usr/bin/env bash
+
+# Script for passing regex filtering of unit tests to py.test conditionally.
+# Needed because tox currently doesn't support conditional logic like this.
+
+posargs=$@
+if [ ${#posargs} -ge 1 ]; then
+    py.test -vvv -s --ignore=hapi -k $1
+else
+    py.test -vvv -s --ignore=hapi
+fi
+TEST_STATUS=$?
+set -e
+
+exit $TEST_STATUS

tox.ini

@@ -17,7 +17,7 @@ whitelist_externals = find
 commands =
   find . -type f -name "*.pyc" -delete
   python -V
-  py.test -vvv -s --ignore=hapi {posargs}
+  {toxinidir}/tools/run-unit-tests.sh {posargs}
 
 [testenv:docs]
 commands =