diff --git a/tests/src/mocks/trigger_mock.hpp b/tests/src/mocks/trigger_mock.hpp
index be40a65..cd0e5f4 100644
--- a/tests/src/mocks/trigger_mock.hpp
+++ b/tests/src/mocks/trigger_mock.hpp
@@ -7,7 +7,7 @@
 class TriggerMock : public interfaces::Trigger
 {
   public:
-    TriggerMock(std::string id)
+    explicit TriggerMock(std::string id)
     {
         using namespace testing;