diff --git a/test/blackbox-tests/test-cases/merlin/suffix.t/run.t b/test/blackbox-tests/test-cases/merlin/suffix.t/run.t
index f688a79955ef..490120298a2f 100644
--- a/test/blackbox-tests/test-cases/merlin/suffix.t/run.t
+++ b/test/blackbox-tests/test-cases/merlin/suffix.t/run.t
@@ -1,5 +1,5 @@
   $ dune build @check
 
-  $ cat .merlin | grep SUFFIX
-  SUFFIX .aml .amli
-  SUFFIX .baml .bamli
+  $ dune ocaml-merlin --dump-config=$(pwd) | grep SUFFIX
+   (SUFFIX ".aml .amli")
+   (SUFFIX ".baml .bamli"))