🐛 fix invariants

include/nlohmann/detail/conversions/to_json.hpp

@@ -132,6 +132,7 @@ struct external_constructor<value_t::array>
     {
         j.m_type = value_t::array;
         j.m_value = arr;
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 
@@ -140,6 +141,7 @@ struct external_constructor<value_t::array>
     {
         j.m_type = value_t::array;
         j.m_value = std::move(arr);
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 
@@ -152,6 +154,7 @@ struct external_constructor<value_t::array>
         using std::end;
         j.m_type = value_t::array;
         j.m_value.array = j.template create<typename BasicJsonType::array_t>(begin(arr), end(arr));
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 
@@ -164,6 +167,9 @@ struct external_constructor<value_t::array>
         for (const bool x : arr)
         {
             j.m_value.array->push_back(x);
+#if JSON_DIAGNOSTICS
+            j.m_value.array->back().m_parent = &j;
+#endif
         }
         j.assert_invariant();
     }
@@ -179,6 +185,7 @@ struct external_constructor<value_t::array>
         {
             std::copy(std::begin(arr), std::end(arr), j.m_value.array->begin());
         }
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 };
@@ -191,6 +198,7 @@ struct external_constructor<value_t::object>
     {
         j.m_type = value_t::object;
         j.m_value = obj;
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 
@@ -199,6 +207,7 @@ struct external_constructor<value_t::object>
     {
         j.m_type = value_t::object;
         j.m_value = std::move(obj);
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 
@@ -211,6 +220,7 @@ struct external_constructor<value_t::object>
 
         j.m_type = value_t::object;
         j.m_value.object = j.template create<typename BasicJsonType::object_t>(begin(obj), end(obj));
+        j.set_parent(j, true);
         j.assert_invariant();
     }
 };

include/nlohmann/detail/input/json_sax.hpp

@@ -236,6 +236,7 @@ class json_sax_dom_parser
 
     bool end_object()
     {
+        ref_stack.back()->set_parent(*ref_stack.back(), true);
         ref_stack.pop_back();
         return true;
     }
@@ -254,6 +255,7 @@ class json_sax_dom_parser
 
     bool end_array()
     {
+        ref_stack.back()->set_parent(*ref_stack.back(), true);
         ref_stack.pop_back();
         return true;
     }
@@ -298,18 +300,12 @@ class json_sax_dom_parser
         if (ref_stack.back()->is_array())
         {
             ref_stack.back()->m_value.array->emplace_back(std::forward<Value>(v));
-#if JSON_DIAGNOSTICS
-            ref_stack.back()->m_value.array->back().m_parent = ref_stack.back();
-#endif
             return &(ref_stack.back()->m_value.array->back());
         }
 
         JSON_ASSERT(ref_stack.back()->is_object());
         JSON_ASSERT(object_element);
         *object_element = BasicJsonType(std::forward<Value>(v));
-#if JSON_DIAGNOSTICS
-        object_element->m_parent = ref_stack.back();
-#endif
         return object_element;
     }
 
@@ -432,10 +428,17 @@ class json_sax_dom_callback_parser
 
     bool end_object()
     {
-        if (ref_stack.back() && !callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::object_end, *ref_stack.back()))
+        if (ref_stack.back())
         {
-            // discard object
-            *ref_stack.back() = discarded;
+            if (!callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::object_end, *ref_stack.back()))
+            {
+                // discard object
+                *ref_stack.back() = discarded;
+            }
+            else
+            {
+                ref_stack.back()->set_parent(*ref_stack.back(), true);
+            }
         }
 
         JSON_ASSERT(!ref_stack.empty());
@@ -483,7 +486,11 @@ class json_sax_dom_callback_parser
         if (ref_stack.back())
         {
             keep = callback(static_cast<int>(ref_stack.size()) - 1, parse_event_t::array_end, *ref_stack.back());
-            if (!keep)
+            if (keep)
+            {
+                ref_stack.back()->set_parent(*ref_stack.back(), true);
+            }
+            else
             {
                 // discard array
                 *ref_stack.back() = discarded;
@@ -582,9 +589,6 @@ class json_sax_dom_callback_parser
         if (ref_stack.back()->is_array())
         {
             ref_stack.back()->m_value.array->emplace_back(std::move(value));
-#if JSON_DIAGNOSTICS
-            ref_stack.back()->m_value.array->back().m_parent = ref_stack.back();
-#endif
             return {true, &(ref_stack.back()->m_value.array->back())};
         }
 
@@ -602,9 +606,6 @@ class json_sax_dom_callback_parser
 
         JSON_ASSERT(object_element);
         *object_element = std::move(value);
-#if JSON_DIAGNOSTICS
-        object_element->m_parent = ref_stack.back();
-#endif
         return {true, object_element};
     }
 

include/nlohmann/detail/input/parser.hpp

@@ -90,7 +90,6 @@ class parser
         {
             json_sax_dom_callback_parser<BasicJsonType> sdp(result, callback, allow_exceptions);
             sax_parse_internal(&sdp);
-            result.assert_invariant();
 
             // in strict mode, input must be completely read
             if (strict && (get_token() != token_type::end_of_input))
@@ -119,7 +118,6 @@ class parser
         {
             json_sax_dom_parser<BasicJsonType> sdp(result, allow_exceptions);
             sax_parse_internal(&sdp);
-            result.assert_invariant();
 
             // in strict mode, input must be completely read
             if (strict && (get_token() != token_type::end_of_input))
@@ -137,6 +135,8 @@ class parser
                 return;
             }
         }
+
+        result.assert_invariant();
     }
 
     /*!