From 0a084ca933466808b17d88828126a5cf431acd94 Mon Sep 17 00:00:00 2001
From: fesil <285451120@qq.com>
Date: Tue, 19 Nov 2024 11:30:40 +0800
Subject: [PATCH] fix json: declare from_json_impl function definitions in
 advance when variant

---
 iguana/json_reader.hpp |  5 ++++-
 test/test_some.cpp     | 15 +++++++++++++--
 2 files changed, 17 insertions(+), 3 deletions(-)

diff --git a/iguana/json_reader.hpp b/iguana/json_reader.hpp
index 765815fe..1485f2bb 100644
--- a/iguana/json_reader.hpp
+++ b/iguana/json_reader.hpp
@@ -25,6 +25,9 @@ IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end);
 template <typename U, typename It, std::enable_if_t<smart_ptr_v<U>, int> = 0>
 IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end);
 
+template <typename U, typename It, std::enable_if_t<variant_v<U>, int> = 0>
+IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end);
+
 template <typename U, typename It,
           std::enable_if_t<ylt_refletable_v<U>, int> = 0>
 IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end) {
@@ -546,7 +549,7 @@ IGUANA_INLINE void from_json_variant(U &value, It &it, It &end,
   end = temp_end;
 }
 
-template <typename U, typename It, std::enable_if_t<variant_v<U>, int> = 0>
+template <typename U, typename It, std::enable_if_t<variant_v<U>, int>>
 IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end) {
   from_json_variant(value, it, end,
                     std::make_index_sequence<
diff --git a/test/test_some.cpp b/test/test_some.cpp
index 97c4f0a8..4286eb4c 100644
--- a/test/test_some.cpp
+++ b/test/test_some.cpp
@@ -217,22 +217,33 @@ TEST_CASE("test throw while parsing an illegal number") {
   }
 }
 
+struct my_variant_nest_t {
+  std::string a;
+  bool operator==(const my_variant_nest_t &o) const { return o.a == a; }
+};
+YLT_REFL(my_variant_nest_t, a);
+
 struct my_variant_t {
   std::string name;
   std::variant<int, std::string> var;
+  std::vector<std::variant<int, my_variant_nest_t>> var1;
 };
-YLT_REFL(my_variant_t, name, var);
+YLT_REFL(my_variant_t, name, var, var1);
 
 TEST_CASE("test variant") {
   std::variant<int, std::string> var;
+  std::variant<int, my_variant_nest_t> var1;
   var = 1;
-  my_variant_t v{"Hi", var}, v2;
+  var1 = my_variant_nest_t{"1234"};
+  my_variant_t v{"Hi", var, {var1}}, v2;
   std::string s;
   iguana::to_json(v, s);
   std::cout << s << std::endl;
 
   iguana::from_json(v2, s);
   CHECK(v.var == v2.var);
+  CHECK(v.var1.size() == v2.var1.size());
+  CHECK(v.var1[0] == v2.var1[0]);
 }
 
 TEST_CASE("test from issues") {