Allow using rfl::AddTagsToVariants with rfl::Generic and same-name structs

The first one was the main reason for this change; the second one was a result
of applying the change. Added tests for both.

The issue was that both `std::vector<Generic>` and `rfl::Object<Generic>` were
getting the type name 'Generic', which caused a compiler error
due to duplicated field names.

This will slightly increase the size of serialized formats when using the
AddTagsToVariants, but it seems like a worthwhile change.

Author: jmcken8

include/rfl/parsing/VariantAlternativeWrapper.hpp

@@ -28,7 +28,7 @@ consteval auto make_tag() {
     return typename T::Tag();
   } else {
     return Literal<
-        internal::remove_namespaces<internal::get_type_name<T>()>()>();
+        internal::get_type_name<T>()>();
   }
 }
 

tests/json/test_add_tag_to_rfl_variant.cpp

@@ -1,9 +1,7 @@
 #include <cassert>
-#include <iostream>
 #include <rfl.hpp>
 #include <rfl/json.hpp>
 #include <string>
-#include <variant>
 #include <vector>
 
 #include "write_and_read.hpp"
@@ -34,6 +32,6 @@ TEST(json, test_add_tag_to_rfl_variant) {
 
   write_and_read<rfl::AddTagsToVariants>(
       vec,
-      R"([{"button_pressed_t":{}},{"button_released_t":{"button":4}},{"key_pressed":{"key":99}},{"int":3}])");
+      R"([{"test_add_tag_to_rfl_variant::button_pressed_t":{}},{"test_add_tag_to_rfl_variant::button_released_t":{"button":4}},{"key_pressed":{"key":99}},{"int":3}])");
 }
 }  // namespace test_add_tag_to_rfl_variant

tests/json/test_add_tag_to_variant.cpp

@@ -1,5 +1,4 @@
 #include <cassert>
-#include <iostream>
 #include <rfl.hpp>
 #include <rfl/json.hpp>
 #include <string>
@@ -10,6 +9,8 @@
 
 namespace test_add_tag_to_variant {
 
+// test 1 -> normal behaviour
+
 struct button_pressed_t {};
 
 struct button_released_t {};
@@ -22,12 +23,54 @@ struct key_pressed_t {
 using my_event_type_t =
     std::variant<button_pressed_t, button_released_t, key_pressed_t, int>;
 
+// test 2 -> 'Generic' within a struct like this cannot be read/written
+// due to the underlying `std::variant` holding two fields with name 'Generic'
+// once 'remove_namespaces' is applied to the type name extraction (which is removed)
+// in the MR this test is added
+struct APIResult {
+  rfl::Generic result;
+};
+struct APIError {
+  rfl::Generic error;
+};
+
+using APICallOutput = rfl::Variant<APIResult, APIError>;
+
+// test 3 -> two structs with the same name in different namespaces should still
+// be serializable
+
+namespace Result {
+struct Message {
+  std::string result;
+};
+}  // namespace Result
+
+namespace Error {
+struct Message {
+  std::string error;
+  int error_id;
+};
+};  // namespace Error
+
+using Messages = std::variant<Result::Message, Error::Message>;
+
 TEST(json, test_add_tag_to_variant) {
   const auto vec = std::vector<my_event_type_t>(
       {button_pressed_t{}, button_released_t{}, key_pressed_t{'c'}, 3});
 
   write_and_read<rfl::AddTagsToVariants>(
       vec,
-      R"([{"button_pressed_t":{}},{"button_released_t":{}},{"key_pressed":{"key":99}},{"int":3}])");
+      R"([{"test_add_tag_to_variant::button_pressed_t":{}},{"test_add_tag_to_variant::button_released_t":{}},{"key_pressed":{"key":99}},{"int":3}])");
+}
+
+TEST(generic, test_add_tag_to_variant_with_generic) {
+  APICallOutput output = APIResult{rfl::to_generic<int>(200)};
+  write_and_read<rfl::AddTagsToVariants>(output,
+    R"({"test_add_tag_to_variant::APIResult":{"result":{"long long":200}}})");
+}
+TEST(generic, test_add_tag_to_variant_different_namespaces) {
+  Messages m = Error::Message{.error="an error", .error_id=2};
+  write_and_read<rfl::AddTagsToVariants>(m,
+    R"({"test_add_tag_to_variant::Error::Message":{"error":"an error","error_id":2}})");
 }
 }  // namespace test_add_tag_to_variant