Allow enum as top level parameter in procedure calls (fixes #10)

CHANGELOG.md

@@ -5,6 +5,14 @@ All notable changes to this project will be documented in this file.
 The format is based on [Keep a Changelog](https://keepachangelog.com/en/1.0.0/),
 and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0.html).
 
+## [0.2.1] - 2020-10-21
+### Changed
+- Updated Catch to version 2.13.2
+- Updated nlohmann_json to 3.9.1
+
+### Fixed
+- Typemapper failed to convert enum parameters on top-level (#10)
+
 ## [0.2.0] - 2020-10-14
 
 ### Added

include/jsonrpccxx/typemapper.hpp

@@ -22,6 +22,9 @@ namespace jsonrpccxx {
   }
   template <typename T>
   constexpr json::value_t GetType(type<T>) {
+    if (std::is_enum<T>::value) {
+      return json::value_t::string;
+    }
     return json::value_t::object;
   }
   constexpr json::value_t GetType(type<void>) { return json::value_t::null; }

test/typemapper.cpp

@@ -146,6 +146,21 @@ bool add_products(const vector<product> &products) {
   return true;
 }
 
+string enumToString(const category& category) {
+  switch (category) {
+  case category::cash_carry: return "cash&carry";
+  case category::order: return "online-order";
+  default: return "unknown category";
+  }
+}
+
+TEST_CASE("test with enum as top level parameter", TEST_MODULE) {
+  MethodHandle  mh = GetHandle(&enumToString);
+
+  json params = R"(["cc"])"_json;
+  CHECK(mh(params) == "cash&carry");
+}
+
 TEST_CASE("test with custom params", TEST_MODULE) {
   MethodHandle mh = GetHandle(&add_products);
   catalog.clear();