diff --git a/tests/cpp/test_learner.cc b/tests/cpp/test_learner.cc
index a69fce19d900..7cd354fe92c2 100644
--- a/tests/cpp/test_learner.cc
+++ b/tests/cpp/test_learner.cc
@@ -46,7 +46,7 @@ TEST(Learner, ParameterValidation) {
   learner->Configure();
   std::string output = testing::internal::GetCapturedStderr();
 
-  ASSERT_TRUE(output.find("Parameters: { Knock Knock, Silence }") != std::string::npos);
+  ASSERT_TRUE(output.find(R"(Parameters: { "Knock Knock", "Silence" })") != std::string::npos);
 }
 
 TEST(Learner, CheckGroup) {