From 366e612a8d7d1877bcf763924342d37c7088df78 Mon Sep 17 00:00:00 2001
From: Loki Astari <Loki.Astari@gmail.com>
Date: Mon, 15 Jul 2024 20:41:31 -0700
Subject: [PATCH] Fix issue 87

---
 src/Serialize/Traits.h             | 16 +++++++++--
 src/Serialize/test/Issue87Test.cpp | 46 ++++++++++++++++++++++++++++++
 2 files changed, 59 insertions(+), 3 deletions(-)
 create mode 100644 src/Serialize/test/Issue87Test.cpp

diff --git a/src/Serialize/Traits.h b/src/Serialize/Traits.h
index f3fb0b52..703465e4 100644
--- a/src/Serialize/Traits.h
+++ b/src/Serialize/Traits.h
@@ -565,10 +565,20 @@ class Traits<DataType BUILDTEMPLATETYPEVALUE(THOR_TYPENAMEVALUEACTION, Count) >
             return Traits<std::remove_cv_t<MemberType>>::getPrintSize(printer, object.*memPtr, false);\
         }                                                               \
                                                                         \
-        template<typename M>                                            \
-        static std::pair<std::size_t, std::size_t> addSizeEachMemberItem(PrinterInterface& printer, MyType const& object, M item) \
+        template<typename M, typename C>                                            \
+        static std::pair<std::size_t, std::size_t> addSizeEachMemberItem(PrinterInterface& printer, MyType const& object, std::pair<C, M*> const& item) \
+        {                                                               \
+            if (!Filter<MyType>::filter(object, item.first, *(item.second))) {          \
+                return std::make_pair(0UL,0UL);                         \
+            }                                                           \
+            auto partSize   = addSizeOneMember(printer, object, item.second);           \
+            auto nameSize   = std::strlen(Override<MyType>::nameOverride(item.first));  \
+            return std::make_pair(partSize + nameSize, 1);              \
+        }                                                               \
+        template<typename M, typename C>                                            \
+        static std::pair<std::size_t, std::size_t> addSizeEachMemberItem(PrinterInterface& printer, MyType const& object, std::pair<C, M MyType::*> const& item) \
         {                                                               \
-            if (!Filter<MyType>::filter(object, item.first, item)) {          \
+            if (!Filter<MyType>::filter(object, item.first, object.*(item.second))) {          \
                 return std::make_pair(0UL,0UL);                         \
             }                                                           \
             auto partSize   = addSizeOneMember(printer, object, item.second);           \
diff --git a/src/Serialize/test/Issue87Test.cpp b/src/Serialize/test/Issue87Test.cpp
new file mode 100644
index 00000000..4a0429bc
--- /dev/null
+++ b/src/Serialize/test/Issue87Test.cpp
@@ -0,0 +1,46 @@
+#include "gtest/gtest.h"
+
+#include "Traits.h"
+#include "BsonThor.h"
+
+#include <optional>
+#include <string>
+
+using ThorsAnvil::Serialize::bsonExporter;
+using namespace std::string_literals;
+
+struct WriteConcern
+{
+    std::optional<int>  w;
+    bool                j   = false;
+};
+
+ThorsAnvil_MakeTrait(WriteConcern,              w, j);
+
+
+TEST(Issue87Test, FieldJOnly)
+{
+    WriteConcern        a;
+    std::stringstream   output;
+    output << bsonExporter(a);
+
+    EXPECT_EQ(  "\x09\x00\x00\x00"
+                "\x08" "j\x00" "\x00"
+                "\x00"s,
+                output.str());
+}
+
+TEST(Issue87Test, FieldJAndW)
+{
+    WriteConcern        a;
+    a.w = 7;
+    std::stringstream   output;
+    output << bsonExporter(a);
+
+    EXPECT_EQ(  "\x10\x00\x00\x00"
+                "\x10" "w\x00" "\x07\x00\x00\x00"
+                "\x08" "j\x00" "\x00"
+                "\x00"s,
+                output.str());
+}
+