Merge pull request #339 from CBookShu/json_optstr_reader

qicosmos · Dec 9, 2024 · 4ea64b7 · 4ea64b7
2 parents 9aca78e + 9d882b2
commit 4ea64b7
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Showing 2 changed files with 17 additions and 2 deletions.
diff --git a/iguana/json_reader.hpp b/iguana/json_reader.hpp
@@ -450,8 +450,6 @@ IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end) {
 template <typename U, typename It, std::enable_if_t<optional_v<U>, int> = 0>
 IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end) {
   skip_ws(it, end);
-  if (it < end && *it == '"')
-    IGUANA_LIKELY { ++it; }
   using T = std::remove_reference_t<U>;
   if (it == end)
     IGUANA_UNLIKELY { throw std::runtime_error("Unexexpected eof"); }
@@ -469,6 +467,8 @@ IGUANA_INLINE void from_json_impl(U &value, It &&it, It &&end) {
     using value_type = typename T::value_type;
     value_type t;
     if constexpr (string_v<value_type> || string_view_v<value_type>) {
+      if (it < end && *it == '"')
+        IGUANA_LIKELY { ++it; }
       from_json_impl<true>(t, it, end);
     }
     else {

diff --git a/test/test_json_files.cpp b/test/test_json_files.cpp
@@ -314,6 +314,21 @@ TEST_CASE("test instruments.json") {
   }
 }
 
+struct test_optstr_reader_null {
+  std::optional<std::string> name;
+};
+YLT_REFL(test_optstr_reader_null, name);
+TEST_CASE("test_optstr_reader") {
+  test_optstr_reader_null v;
+  v.name = "name";  // optional<string> begin with 'n'
+  std::string json;
+  iguana::to_json(v, json);
+
+  test_optstr_reader_null v1;
+  iguana::from_json(v1, json);
+  CHECK(v.name == v1.name);
+}
+
 // doctest comments
 // 'function' : must be 'attribute' - see issue #182
 DOCTEST_MSVC_SUPPRESS_WARNING_WITH_PUSH(4007) int main(int argc, char **argv) {