From 5f6670a5c0a52556d66a1fb51ad3c8b30d8804bd Mon Sep 17 00:00:00 2001
From: Maksim Golev <mgolev@htc-cs.ru>
Date: Thu, 13 Apr 2023 12:13:48 +0400
Subject: [PATCH] fix(76268): Fix invalid behavior for ignored properties with
 "new" modifier of derived class.

---
 .../gen/JsonSourceGenerator.Parser.cs         |  2 +-
 .../Serialization/Metadata/JsonTypeInfo.cs    |  3 ++-
 .../tests/Common/PropertyVisibilityTests.cs   | 22 +++++++++++++++++++
 .../Serialization/PropertyVisibilityTests.cs  |  2 ++
 4 files changed, 27 insertions(+), 2 deletions(-)

diff --git a/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Parser.cs b/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Parser.cs
index f64624dddb884..73d5355d9351f 100644
--- a/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Parser.cs
+++ b/src/libraries/System.Text.Json/gen/JsonSourceGenerator.Parser.cs
@@ -1011,7 +1011,7 @@ private static void CacheMember(
                 if (propGenSpec.DefaultIgnoreCondition == JsonIgnoreCondition.Always)
                 {
                     ignoredMembers ??= new();
-                    ignoredMembers.Add(propGenSpec.MemberName, memberInfo);
+                    ignoredMembers[propGenSpec.MemberName] = memberInfo;
                 }
             }
 
diff --git a/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs b/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs
index b7ebe9b005473..aa6c84ece702e 100644
--- a/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs
+++ b/src/libraries/System.Text.Json/src/System/Text/Json/Serialization/Metadata/JsonTypeInfo.cs
@@ -1405,7 +1405,8 @@ public void AddPropertyWithConflictResolution(JsonPropertyInfo jsonPropertyInfo,
 
                 if (jsonPropertyInfo.IsIgnored)
                 {
-                    (state.IgnoredProperties ??= new()).Add(memberName, jsonPropertyInfo);
+                    state.IgnoredProperties ??= new();
+                    state.IgnoredProperties[memberName] = jsonPropertyInfo;
                 }
             }
         }
diff --git a/src/libraries/System.Text.Json/tests/Common/PropertyVisibilityTests.cs b/src/libraries/System.Text.Json/tests/Common/PropertyVisibilityTests.cs
index e0e4e3ab2dd06..60bb9ab11a3f2 100644
--- a/src/libraries/System.Text.Json/tests/Common/PropertyVisibilityTests.cs
+++ b/src/libraries/System.Text.Json/tests/Common/PropertyVisibilityTests.cs
@@ -241,6 +241,22 @@ public async Task Ignore_BasePublicPropertyIgnored_ConflictWithDerivedPrivate()
             Assert.Equal("NewDefaultValue", ((ClassWithIgnoredPublicPropertyAndNewSlotPrivate)obj).MyString);
         }
 
+        [Fact]
+        public async void Ignore_BasePublicPropertyIgnored_ConflictWithDerivedPublicPropertyIgnored()
+        {
+            var obj = new ClassWithIgnoredPublicPropertyAndNewSlotPublicAndIgnoredToo();
+
+            string json = await Serializer.SerializeWrapper(obj);
+
+            Assert.Equal(@"{}", json);
+
+            json = @"{""MyString"":""NewValue""}";
+            obj = await Serializer.DeserializeWrapper<ClassWithIgnoredPublicPropertyAndNewSlotPublicAndIgnoredToo>(json);
+
+            Assert.Equal("DefaultValue", ((ClassWithIgnoredPublicProperty)obj).MyString);
+            Assert.Equal("NewDefaultValue", obj.MyString);
+        }
+
         [Fact]
         public async Task Ignore_VerifyNoReferenceToGetterAndSetter()
         {
@@ -812,6 +828,12 @@ public class ClassWithIgnoredPublicPropertyAndNewSlotPrivate : ClassWithIgnoredP
             internal new string MyString { get; set; } = "NewDefaultValue";
         }
 
+        public class ClassWithIgnoredPublicPropertyAndNewSlotPublicAndIgnoredToo : ClassWithIgnoredPublicProperty
+        {
+            [JsonIgnore]
+            public new string MyString { get; set; } = "NewDefaultValue";
+        }
+
         public class ClassWithIgnoredPropertyNamingConflictPrivate
         {
             [JsonIgnore]
diff --git a/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/Serialization/PropertyVisibilityTests.cs b/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/Serialization/PropertyVisibilityTests.cs
index 3c15522874cfb..4cbed0897b184 100644
--- a/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/Serialization/PropertyVisibilityTests.cs
+++ b/src/libraries/System.Text.Json/tests/System.Text.Json.SourceGeneration.Tests/Serialization/PropertyVisibilityTests.cs
@@ -174,6 +174,7 @@ public override async Task HonorJsonPropertyName_PrivateSetter()
         [JsonSerializable(typeof(Class_PropertyWith_ProtectedInitOnlySetter))]
         [JsonSerializable(typeof(ClassWithIgnoredPublicProperty))]
         [JsonSerializable(typeof(ClassWithIgnoredPublicPropertyAndNewSlotPrivate))]
+        [JsonSerializable(typeof(ClassWithIgnoredPublicPropertyAndNewSlotPublicAndIgnoredToo))]
         [JsonSerializable(typeof(ClassWithIgnoredPropertyPolicyConflictPublic))]
         [JsonSerializable(typeof(ClassWithIgnoredPropertyNamingConflictPrivate))]
         [JsonSerializable(typeof(ClassWithIgnoredNewSlotProperty))]
@@ -419,6 +420,7 @@ public void PublicContextAndJsonSerializerOptions()
         [JsonSerializable(typeof(Class_PropertyWith_ProtectedInitOnlySetter))]
         [JsonSerializable(typeof(ClassWithIgnoredPublicProperty))]
         [JsonSerializable(typeof(ClassWithIgnoredPublicPropertyAndNewSlotPrivate))]
+        [JsonSerializable(typeof(ClassWithIgnoredPublicPropertyAndNewSlotPublicAndIgnoredToo))]
         [JsonSerializable(typeof(ClassWithIgnoredPropertyPolicyConflictPublic))]
         [JsonSerializable(typeof(ClassWithIgnoredPropertyNamingConflictPrivate))]
         [JsonSerializable(typeof(ClassWithIgnoredNewSlotProperty))]