diff --git a/tests/run.sh b/tests/run.sh
index 71a08057..5ca1de9c 100755
--- a/tests/run.sh
+++ b/tests/run.sh
@@ -12,6 +12,9 @@
 
 set -e
 
+export SHELL=/bin/sh
+export HOME=/dev/null
+
 # Be verbose on Travis.
 if [ "$CI" = true ]; then
     set -x