diff --git a/test/functional/3rd-party/3rd-party-repo-add-certificate.bats b/test/functional/3rd-party/3rd-party-repo-add-certificate.bats
index 9ec4d90a..9db12566 100755
--- a/test/functional/3rd-party/3rd-party-repo-add-certificate.bats
+++ b/test/functional/3rd-party/3rd-party-repo-add-certificate.bats
@@ -29,7 +29,7 @@ global_teardown() {
 		return
 	fi
 
-	if [ ! -z "${CERT_WAS_INSTALLED}" ]; then
+	if [ -n "${CERT_WAS_INSTALLED}" ]; then
 		sudo rm usr/share/clear/update-ca/Swupd_Root.pem
 	fi
 }