From 6fffb96b660cac7a77a55b3bfa829d9b4aa8f724 Mon Sep 17 00:00:00 2001
From: PengZheng <howtofly@gmail.com>
Date: Sat, 20 Jan 2024 15:20:04 +0800
Subject: [PATCH] Support nullptr when serialize text.

---
 libs/dfi/gtest/src/json_serializer_tests.cpp | 40 ++++++++++++++++++++
 libs/dfi/src/json_serializer.c               |  6 ++-
 2 files changed, 44 insertions(+), 2 deletions(-)

diff --git a/libs/dfi/gtest/src/json_serializer_tests.cpp b/libs/dfi/gtest/src/json_serializer_tests.cpp
index 3c88d40dc..20bdf7253 100644
--- a/libs/dfi/gtest/src/json_serializer_tests.cpp
+++ b/libs/dfi/gtest/src/json_serializer_tests.cpp
@@ -946,3 +946,43 @@ TEST_F(JsonSerializerTests, SerializationDeserilizationTest) {
     dynType_free(type, inst);
     dynType_destroy(type);
 }
+
+TEST_F(JsonSerializerTests, SerializationDeserilizationNullStringTest) {
+    dyn_type *type;
+    void *inst;
+    int rc;
+    rc = dynType_parseWithStr("t", nullptr, nullptr, &type);
+    ASSERT_EQ(0, rc);
+    json_auto_t* root = json_null();
+    rc = jsonSerializer_deserializeJson(type, root, &inst);
+    ASSERT_EQ(0, rc);
+    EXPECT_EQ(nullptr, *(char**)inst);
+
+    json_auto_t* result = nullptr;
+    rc = jsonSerializer_serializeJson(type, inst, &result);
+    ASSERT_EQ(0, rc);
+    EXPECT_TRUE(json_equal(root, result));
+    dynType_free(type, inst);
+    dynType_destroy(type);
+
+}
+
+TEST_F(JsonSerializerTests, SerializationDeserilizationStringTest) {
+    dyn_type *type;
+    void *inst;
+    int rc;
+    rc = dynType_parseWithStr("t", nullptr, nullptr, &type);
+    ASSERT_EQ(0, rc);
+    json_auto_t* root = json_loads(R"("hello")", JSON_DECODE_ANY, NULL);
+    ASSERT_NE(nullptr, root);
+    rc = jsonSerializer_deserializeJson(type, root, &inst);
+    ASSERT_EQ(0, rc);
+    EXPECT_STREQ("hello", *(char**)inst);
+
+    json_auto_t* result = nullptr;
+    rc = jsonSerializer_serializeJson(type, inst, &result);
+    ASSERT_EQ(0, rc);
+    EXPECT_TRUE(json_equal(root, result));
+    dynType_free(type, inst);
+    dynType_destroy(type);
+}
diff --git a/libs/dfi/src/json_serializer.c b/libs/dfi/src/json_serializer.c
index f6f964f9b..d98451fe1 100644
--- a/libs/dfi/src/json_serializer.c
+++ b/libs/dfi/src/json_serializer.c
@@ -320,9 +320,11 @@ static int jsonSerializer_writeAny(const dyn_type* type, const void* input, json
         case 'D' :
             val = json_real(*(const double*)input);
             break;
-        case 't' :
-            val = json_string(*(const char **) input);
+        case 't' : {
+            const char *strValue = *(const char **) input;
+            val = (strValue != NULL) ? json_string(strValue) : json_null();
             break;
+        }
         case 'E':
             status = jsonSerializer_writeEnum(type, *(const int32_t*)input, &val);
             break;