diff --git a/tests/libtest.sh b/tests/libtest.sh
index 04e206bf..b6e57a1e 100644
--- a/tests/libtest.sh
+++ b/tests/libtest.sh
@@ -55,7 +55,7 @@ assert_not_has_file () {
 }
 
 assert_file_has_content () {
-    if ! grep -q "$2" "$1"; then
+    if ! grep -q -e "$2" "$1"; then
 	echo 1>&2 "File '$1' doesn't match regexp '$2'"; exit 1
     fi
 }