diff --git a/share/spack/qa/run-unit-tests b/share/spack/qa/run-unit-tests
index 9cace0dfd66..d2ce9647aff 100755
--- a/share/spack/qa/run-unit-tests
+++ b/share/spack/qa/run-unit-tests
@@ -44,8 +44,7 @@ spack config get compilers
 # Run unit tests with code coverage
 if [[ "$TRAVIS_PYTHON_VERSION" == 2.7 ]]; then
     coverage run bin/spack install -v libdwarf
-    coverage run bin/spack test "$@"
-    coverage combine
+    coverage run bin/spack test "$@" && coverage combine
 else
     spack install -v libdwarf
     spack test "$@"