diff --git a/test/src/unit-class_lexer.cpp b/test/src/unit-class_lexer.cpp
index 214cae75b..468e1f520 100644
--- a/test/src/unit-class_lexer.cpp
+++ b/test/src/unit-class_lexer.cpp
@@ -87,22 +87,22 @@ TEST_CASE("lexer class")
 
     SECTION("token_type_name")
     {
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::uninitialized)) == "<uninitialized>"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::literal_true)) == "true literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::literal_false)) == "false literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::literal_null)) == "null literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::value_string)) == "string literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::value_unsigned)) == "number literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::value_integer)) == "number literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::value_float)) == "number literal"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::begin_array)) == "'['"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::begin_object)) == "'{'"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::end_array)) == "']'"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::end_object)) == "'}'"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::name_separator)) == "':'"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::value_separator)) == "','"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::parse_error)) == "<parse error>"));
-        CHECK((json::lexer::token_type_name(std::string(json::lexer::token_type::end_of_input)) == "end of input"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::uninitialized)) == "<uninitialized>"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::literal_true)) == "true literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::literal_false)) == "false literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::literal_null)) == "null literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::value_string)) == "string literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::value_unsigned)) == "number literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::value_integer)) == "number literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::value_float)) == "number literal"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::begin_array)) == "'['"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::begin_object)) == "'{'"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::end_array)) == "']'"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::end_object)) == "'}'"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::name_separator)) == "':'"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::value_separator)) == "','"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::parse_error)) == "<parse error>"));
+        CHECK((std::string(json::lexer::token_type_name(json::lexer::token_type::end_of_input)) == "end of input"));
     }
 
     SECTION("parse errors on first character")