Address remaining warnings from DataContractSerialization (#51200)

* Address remaining warnings from DataContractSerialization

* Refactor MemberTypes declaration

* Remove Unused UnconditionalSuppressMessages

* Addressing some PR Feedback

* Suppress MakeGenericMethod calls in AccessorBuilder

* Suppressing error in NullPrimitiveDataContract constructor

* Suppress other MakeGenericMethod linker warnings

* Address remaining feedback and move trimmer string to DataContract

* Addressing some nits

* Fix typo and remove unnecesary usings

src/libraries/System.Private.DataContractSerialization/src/System/Runtime/Serialization/AccessorBuilder.cs

@@ -3,6 +3,7 @@
 
 using System;
 using System.Collections.Generic;
+using System.Diagnostics.CodeAnalysis;
 using System.Linq;
 using System.Reflection;
 using System.Runtime.Serialization;
@@ -23,12 +24,18 @@ internal static class FastInvokerBuilder
         private static readonly MethodInfo s_createSetterInternal = typeof(FastInvokerBuilder).GetMethod(nameof(CreateSetterInternal), BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static)!;
         private static readonly MethodInfo s_make = typeof(FastInvokerBuilder).GetMethod(nameof(Make), BindingFlags.NonPublic | BindingFlags.Public | BindingFlags.Static)!;
 
-        public static Func<object> GetMakeNewInstanceFunc(Type type)
+        [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2060:MakeGenericMethod",
+            Justification = "The call to MakeGenericMethod is safe due to the fact that we are preserving the constructors of type which is what Make() is doing.")]
+        public static Func<object> GetMakeNewInstanceFunc(
+            [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicParameterlessConstructor)]
+            Type type)
         {
             Func<object> make = s_make.MakeGenericMethod(type).CreateDelegate<Func<object>>();
             return make;
         }
 
+        [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2060:MakeGenericMethod",
+            Justification = "The call to MakeGenericMethod is safe due to the fact that FastInvokerBuilder.CreateGetterInternal<T, T1> is not annotated.")]
         public static Getter CreateGetter(MemberInfo memberInfo)
         {
             if (memberInfo is PropertyInfo propInfo)
@@ -51,6 +58,8 @@ public static Getter CreateGetter(MemberInfo memberInfo)
             }
         }
 
+        [UnconditionalSuppressMessage("ReflectionAnalysis", "IL2060:MakeGenericMethod",
+            Justification = "The call to MakeGenericMethod is safe due to the fact that FastInvokerBuilder.CreateSetterInternal<T, T1> is not annotated.")]
         public static Setter CreateSetter(MemberInfo memberInfo)
         {
             if (memberInfo is PropertyInfo)

src/libraries/System.Private.DataContractSerialization/src/System/Runtime/Serialization/ClassDataContract.cs

@@ -33,11 +33,21 @@ internal sealed class ClassDataContract : DataContract
 
         private bool _isScriptObject;
 
+        internal const DynamicallyAccessedMemberTypes DataContractPreserveMemberTypes =
+            DynamicallyAccessedMemberTypes.PublicMethods |
+            DynamicallyAccessedMemberTypes.NonPublicMethods |
+            DynamicallyAccessedMemberTypes.PublicConstructors |
+            DynamicallyAccessedMemberTypes.NonPublicConstructors |
+            DynamicallyAccessedMemberTypes.PublicFields |
+            DynamicallyAccessedMemberTypes.PublicProperties;
+
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         internal ClassDataContract(Type type) : base(new ClassDataContractCriticalHelper(type))
         {
             InitClassDataContract();
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         private ClassDataContract(Type type, XmlDictionaryString ns, string[] memberNames) : base(new ClassDataContractCriticalHelper(type, ns, memberNames))
         {
             InitClassDataContract();
@@ -65,6 +75,7 @@ internal List<DataMember>? Members
 
         public XmlDictionaryString?[]? ChildElementNamespaces
         {
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get
             {
                 if (_childElementNamespaces == null)
@@ -122,6 +133,7 @@ internal MethodInfo? ExtensionDataSetMethod
 
         public override DataContractDictionary? KnownDataContracts
         {
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get
             { return _helper.KnownDataContracts; }
         }
@@ -228,13 +240,15 @@ internal bool CreateNewInstanceViaDefaultConstructor([NotNullWhen(true)] out obj
             return true;
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         private XmlFormatClassWriterDelegate CreateXmlFormatWriterDelegate()
         {
             return new XmlFormatWriterGenerator().GenerateClassWriter(this);
         }
 
         internal XmlFormatClassWriterDelegate XmlFormatWriterDelegate
         {
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get
             {
                 if (_helper.XmlFormatWriterDelegate == null)
@@ -256,13 +270,15 @@ internal XmlFormatClassWriterDelegate XmlFormatWriterDelegate
             }
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         private XmlFormatClassReaderDelegate CreateXmlFormatReaderDelegate()
         {
             return new XmlFormatReaderGenerator().GenerateClassReader(this);
         }
 
         internal XmlFormatClassReaderDelegate XmlFormatReaderDelegate
         {
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get
             {
                 if (_helper.XmlFormatReaderDelegate == null)
@@ -284,6 +300,7 @@ internal XmlFormatClassReaderDelegate XmlFormatReaderDelegate
             }
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         internal static ClassDataContract CreateClassDataContractForKeyValue(Type type, XmlDictionaryString ns, string[] memberNames)
         {
             ClassDataContract? cdc = (ClassDataContract?)DataContract.GetDataContractFromGeneratedAssembly(type);
@@ -317,6 +334,7 @@ internal static void CheckAndAddMember(List<DataMember> members, DataMember memb
             members.Add(memberContract);
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         internal static XmlDictionaryString? GetChildNamespaceToDeclare(DataContract dataContract, Type childType, XmlDictionary dictionary)
         {
             childType = DataContract.UnwrapNullableType(childType);
@@ -342,7 +360,9 @@ private static bool IsArraySegment(Type t)
         ///            is therefore marked SRR
         /// Safe - does not let caller influence isNonAttributedType calculation; no harm in leaking value
         /// </SecurityNote>
-        internal static bool IsNonAttributedTypeValidForSerialization(Type type)
+        internal static bool IsNonAttributedTypeValidForSerialization(
+            [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)]
+            Type type)
         {
             if (type.IsArray)
                 return false;
@@ -437,6 +457,7 @@ internal static bool IsNonSerializedMember(Type type, string memberName)
                 && members.Contains(memberName);
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         private XmlDictionaryString?[]? CreateChildElementNamespaces()
         {
             if (Members == null)
@@ -464,6 +485,7 @@ private void EnsureMethodsImported()
             _helper.EnsureMethodsImported();
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         public override void WriteXmlValue(XmlWriterDelegator xmlWriter, object obj, XmlObjectSerializerWriteContext? context)
         {
             Debug.Assert(context != null);
@@ -475,6 +497,7 @@ public override void WriteXmlValue(XmlWriterDelegator xmlWriter, object obj, Xml
             XmlFormatWriterDelegate(xmlWriter, obj, context, this);
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         public override object? ReadXmlValue(XmlReaderDelegator xmlReader, XmlObjectSerializerReadContext? context)
         {
             if (_isScriptObject)
@@ -711,7 +734,9 @@ private sealed class ClassDataContractCriticalHelper : DataContract.DataContract
             public XmlDictionaryString[]? MemberNames;
             public XmlDictionaryString[]? MemberNamespaces;
 
-            internal ClassDataContractCriticalHelper(Type type) : base(type)
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
+            internal ClassDataContractCriticalHelper([DynamicallyAccessedMembers(DataContractPreserveMemberTypes)]
+                Type type) : base(type)
             {
                 XmlQualifiedName stableName = GetStableNameAndSetHasDataContract(type);
                 if (type == Globals.TypeOfDBNull)
@@ -823,7 +848,10 @@ internal ClassDataContractCriticalHelper(Type type) : base(type)
                     Globals.TypeOfScriptObject_IsAssignableFrom(this.UnderlyingType);
             }
 
-            internal ClassDataContractCriticalHelper(Type type, XmlDictionaryString ns, string[] memberNames) : base(type)
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
+            internal ClassDataContractCriticalHelper(
+                [DynamicallyAccessedMembers(DataContractPreserveMemberTypes)]
+                Type type, XmlDictionaryString ns, string[] memberNames) : base(type)
             {
                 this.StableName = new XmlQualifiedName(GetStableNameAndSetHasDataContract(type).Name, ns.Value);
                 ImportDataMembers();
@@ -896,6 +924,7 @@ private void EnsureIsReferenceImported(Type type)
 
             [MemberNotNull(nameof(_members))]
             [MemberNotNull(nameof(Members))]
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             private void ImportDataMembers()
             {
                 Type type = this.UnderlyingType;
@@ -1075,6 +1104,7 @@ private static bool CanSerializeMember(FieldInfo? field)
                 return field != null && !ClassDataContract.IsNonSerializedMember(field.DeclaringType!, field.Name);
             }
 
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             private bool SetIfGetOnlyCollection(DataMember memberContract)
             {
                 //OK to call IsCollection here since the use of surrogated collection types is not supported in get-only scenarios
@@ -1148,6 +1178,7 @@ private void SetIfMembersHaveConflict(List<DataMember> members)
                 }
             }
 
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             private XmlQualifiedName GetStableNameAndSetHasDataContract(Type type)
             {
                 return DataContract.GetStableName(type, out _hasDataContract);
@@ -1160,7 +1191,9 @@ private XmlQualifiedName GetStableNameAndSetHasDataContract(Type type)
             ///            is dependent on the correct calculation of hasDataContract
             /// Safe - does not let caller influence isNonAttributedType calculation; no harm in leaking value
             /// </SecurityNote>
-            private void SetIsNonAttributedType(Type type)
+            private void SetIsNonAttributedType(
+                [DynamicallyAccessedMembers(DynamicallyAccessedMemberTypes.PublicConstructors | DynamicallyAccessedMemberTypes.NonPublicConstructors)]
+                Type type)
             {
                 _isNonAttributedType = !type.IsSerializable && !_hasDataContract && IsNonAttributedTypeValidForSerialization(type);
             }
@@ -1314,6 +1347,8 @@ internal MethodInfo? ExtensionDataSetMethod
 
             internal override DataContractDictionary? KnownDataContracts
             {
+
+                [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
                 get
                 {
                     if (_knownDataContracts != null)
@@ -1362,7 +1397,10 @@ internal bool IsNonAttributedType
                 get { return _isNonAttributedType; }
             }
 
-            private void SetKeyValuePairAdapterFlags(Type type)
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
+            private void SetKeyValuePairAdapterFlags(
+                [DynamicallyAccessedMembers(DataContractPreserveMemberTypes)]
+                Type type)
             {
                 if (type.IsGenericType && type.GetGenericTypeDefinition() == Globals.TypeOfKeyValuePairAdapter)
                 {
@@ -1491,6 +1529,7 @@ public int Compare(Member x, Member y)
                 internal static DataMemberConflictComparer Singleton = new DataMemberConflictComparer();
             }
 
+            [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             internal ClassDataContractCriticalHelper Clone()
             {
                 ClassDataContractCriticalHelper clonedHelper = new ClassDataContractCriticalHelper(this.UnderlyingType);
@@ -1552,6 +1591,7 @@ internal Type ObjectType
             }
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         internal ClassDataContract Clone()
         {
             ClassDataContract clonedDc = new ClassDataContract(this.UnderlyingType);
@@ -1565,6 +1605,7 @@ internal ClassDataContract Clone()
             return clonedDc;
         }
 
+        [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
         internal void UpdateNamespaceAndMembers(Type type, XmlDictionaryString ns, string[] memberNames)
         {
             this.StableName = new XmlQualifiedName(GetStableName(type).Name, ns.Value);