API cleanup.

src/libraries/System.Private.DataContractSerialization/src/Resources/Strings.resx

@@ -1071,6 +1071,9 @@
   <data name="DupTypeContractInDataContractSet" xml:space="preserve">
     <value>DataContract for type '{0}' cannot be added to DataContractSet since type '{1}' with the same data contract name '{2}' in namespace '{3}' is already present and the contracts are not equivalent.</value>
   </data>
+  <data name="GenericTypeNameMismatch" xml:space="preserve">
+    <value>DataContract name '{0}' from namespace '{1}' does not match the generic name '{2}' from namespace '{3}'.</value>
+  </data>
   <data name="GenericTypeNotExportable" xml:space="preserve">
     <value>Type '{0}' cannot be exported as a schema type because it is an open generic type. You can only export a generic type if all its generic parameter types are actual types.</value>
   </data>

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

@@ -11,7 +11,7 @@
 using System.Threading;
 using System.Xml;
 
-using DataContractDictionary = System.Collections.Generic.IDictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
+using DataContractDictionary = System.Collections.Generic.Dictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
 
 namespace System.Runtime.Serialization
 {
@@ -20,11 +20,11 @@ internal sealed class ClassDataContract : DataContract
         internal const string ContractTypeString = nameof(ClassDataContract);
         public override string? ContractType => ContractTypeString;
 
-        public XmlDictionaryString[]? ContractNamespaces;
+        internal XmlDictionaryString[]? ContractNamespaces;
 
-        public XmlDictionaryString[]? MemberNames;
+        internal XmlDictionaryString[]? MemberNames;
 
-        public XmlDictionaryString[]? MemberNamespaces;
+        internal XmlDictionaryString[]? MemberNamespaces;
 
         private XmlDictionaryString?[]? _childElementNamespaces;
 
@@ -63,13 +63,13 @@ internal ClassDataContract? BaseClassContract
             set => _helper.BaseClassContract = value;
         }
 
-        public override IList<DataMember>? Members
+        public override List<DataMember>? Members
         {
             get => _helper.Members;
             internal set => _helper.Members = value;
         }
 
-        public XmlDictionaryString?[]? ChildElementNamespaces
+        internal XmlDictionaryString?[]? ChildElementNamespaces
         {
             [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get
@@ -578,7 +578,7 @@ private sealed class ClassDataContractCriticalHelper : DataContract.DataContract
             private static Type[]? s_serInfoCtorArgs;
 
             private ClassDataContract? _baseContract;
-            private IList<DataMember>? _members;
+            private List<DataMember>? _members;
             private MethodInfo? _onSerializing, _onSerialized;
             private MethodInfo? _onDeserializing, _onDeserialized;
             private MethodInfo? _extensionDataSetMethod;
@@ -599,9 +599,9 @@ private sealed class ClassDataContractCriticalHelper : DataContract.DataContract
             private bool _hasDataContract;
             private bool _hasExtensionData;
 
-            public XmlDictionaryString[]? ContractNamespaces;
-            public XmlDictionaryString[]? MemberNames;
-            public XmlDictionaryString[]? MemberNamespaces;
+            internal XmlDictionaryString[]? ContractNamespaces;
+            internal XmlDictionaryString[]? MemberNames;
+            internal XmlDictionaryString[]? MemberNamespaces;
 
             [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             internal ClassDataContractCriticalHelper([DynamicallyAccessedMembers(DataContractPreserveMemberTypes)]
@@ -1132,7 +1132,7 @@ internal ClassDataContract? BaseClassContract
                 }
             }
 
-            internal IList<DataMember>? Members
+            internal List<DataMember>? Members
             {
                 get => _members;
                 set => _members = value;
@@ -1255,7 +1255,7 @@ internal override bool IsISerializable
 
             internal XmlFormatClassReaderDelegate? XmlFormatReaderDelegate { get; set; }
 
-            public XmlDictionaryString?[]? ChildElementNamespaces { get; set; }
+            internal XmlDictionaryString?[]? ChildElementNamespaces { get; set; }
 
             private static Type[] SerInfoCtorArgs => s_serInfoCtorArgs ??= new Type[] { typeof(SerializationInfo), typeof(StreamingContext) };
 
@@ -1292,15 +1292,15 @@ public int Compare(Member x, Member y)
         }
 
         [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
-        public override DataContract BindGenericParameters(DataContract[] paramContracts, IDictionary<DataContract, DataContract> boundContracts)
+        internal override DataContract BindGenericParameters(DataContract[] paramContracts, Dictionary<DataContract, DataContract>? boundContracts = null)
         {
             Type type = UnderlyingType;
             if (!type.IsGenericType || !type.ContainsGenericParameters)
                 return this;
 
             lock (this)
             {
-                if (boundContracts.TryGetValue(this, out DataContract? boundContract))
+                if (boundContracts != null && boundContracts.TryGetValue(this, out DataContract? boundContract))
                     return boundContract;
 
                 XmlQualifiedName stableName;
@@ -1341,6 +1341,7 @@ public override DataContract BindGenericParameters(DataContract[] paramContracts
                     boundType = type.MakeGenericType(paramTypes);
                 }
                 ClassDataContract boundClassContract = new ClassDataContract(boundType);
+                boundContracts ??= new Dictionary<DataContract, DataContract>();
                 boundContracts.Add(this, boundClassContract);
                 boundClassContract.StableName = CreateQualifiedName(DataContract.ExpandGenericParameters(XmlConvert.DecodeName(stableName.Name), new GenericNameProvider(DataContract.GetClrTypeFullName(UnderlyingType), genericParams)), stableName.Namespace);
                 if (BaseClassContract != null)

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

@@ -12,7 +12,7 @@
 using System.Threading;
 using System.Xml;
 
-using DataContractDictionary = System.Collections.Generic.IDictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
+using DataContractDictionary = System.Collections.Generic.Dictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
 
 namespace System.Runtime.Serialization
 {
@@ -153,7 +153,7 @@ private void InitCollectionDataContract(DataContract? sharedTypeContract)
 
         internal Type ItemType => _helper.ItemType;
 
-        public DataContract ItemContract
+        internal DataContract ItemContract
         {
             [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get => _itemContract ?? _helper.ItemContract;
@@ -173,7 +173,7 @@ internal string ItemName
             set => _helper.ItemName = value;
         }
 
-        public XmlDictionaryString CollectionItemName => _collectionItemName;
+        internal XmlDictionaryString CollectionItemName => _collectionItemName;
 
         internal string? KeyName
         {
@@ -203,7 +203,7 @@ public override DataContract BaseContract
 
         internal bool IsDictionary => KeyName != null;
 
-        public XmlDictionaryString? ChildElementNamespace
+        internal XmlDictionaryString? ChildElementNamespace
         {
             [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get
@@ -629,7 +629,7 @@ internal bool IsConstructorCheckRequired
                 set => _isConstructorCheckRequired = value;
             }
 
-            public XmlDictionaryString CollectionItemName => _collectionItemName;
+            internal XmlDictionaryString CollectionItemName => _collectionItemName;
 
             internal string? KeyName
             {
@@ -645,11 +645,11 @@ internal string? ValueName
 
             internal bool IsDictionary => KeyName != null;
 
-            public string? SerializationExceptionMessage => _serializationExceptionMessage;
+            internal string? SerializationExceptionMessage => _serializationExceptionMessage;
 
-            public string? DeserializationExceptionMessage => _deserializationExceptionMessage;
+            internal string? DeserializationExceptionMessage => _deserializationExceptionMessage;
 
-            public XmlDictionaryString? ChildElementNamespace
+            internal XmlDictionaryString? ChildElementNamespace
             {
                 get => _childElementNamespace;
                 set => _childElementNamespace = value;
@@ -1330,10 +1330,10 @@ private static bool IsKnownInterface(Type type)
         }
 
         [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
-        public override DataContract BindGenericParameters(DataContract[] paramContracts, IDictionary<DataContract, DataContract> boundContracts)
+        internal override DataContract BindGenericParameters(DataContract[] paramContracts, Dictionary<DataContract, DataContract>? boundContracts = null)
         {
             DataContract boundContract;
-            if (boundContracts.TryGetValue(this, out boundContract!))
+            if (boundContracts != null && boundContracts.TryGetValue(this, out boundContract!))
                 return boundContract;
 
             // NOTE TODO smolloy - this type-binding ('boundType') stuff is new. We did not do this in NetFx. We used to use default constructors and let the
@@ -1349,6 +1349,7 @@ public override DataContract BindGenericParameters(DataContract[] paramContracts
             Type boundType = type.MakeGenericType(paramTypes);
 
             CollectionDataContract boundCollectionContract = new CollectionDataContract(boundType);
+            boundContracts ??= new Dictionary<DataContract, DataContract>();
             boundContracts.Add(this, boundCollectionContract);
             boundCollectionContract.ItemContract = ItemContract.BindGenericParameters(paramContracts, boundContracts);
             boundCollectionContract.IsItemTypeNullable = !boundCollectionContract.ItemContract.IsValueType;

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

@@ -14,7 +14,7 @@
 using System.Text;
 using System.Xml;
 
-using DataContractDictionary = System.Collections.Generic.IDictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
+using DataContractDictionary = System.Collections.Generic.Dictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
 
 namespace System.Runtime.Serialization
 {
@@ -207,11 +207,11 @@ public virtual DataContract? BaseContract
             get => null;
         }
 
-        public virtual GenericInfo? GenericInfo
+        internal GenericInfo? GenericInfo
         {
             [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
             get => _helper.GenericInfo;
-            internal set => _helper.GenericInfo = value;
+            set => _helper.GenericInfo = value;
         }
 
         public virtual DataContractDictionary? KnownDataContracts
@@ -259,7 +259,7 @@ public virtual bool IsKeyValue(out string? keyName, out string? valueName, out s
             return false;
         }
 
-        public virtual IList<DataMember>? Members
+        public virtual List<DataMember>? Members
         {
             get => null;
             internal set { }
@@ -274,7 +274,7 @@ internal virtual void WriteRootElement(XmlWriterDelegator writer, XmlDictionaryS
         }
 
         [RequiresUnreferencedCode(DataContract.SerializerTrimmerWarning)]
-        public virtual DataContract BindGenericParameters(DataContract[] paramContracts, IDictionary<DataContract, DataContract> boundContracts)
+        internal virtual DataContract BindGenericParameters(DataContract[] paramContracts, Dictionary<DataContract, DataContract>? boundContracts = null)
         {
             return this;
         }
@@ -2016,7 +2016,7 @@ private static void ImportKnownTypeAttributes(Type? type, Dictionary<Type, Type>
                         collectionDataContract.ItemType.GetGenericTypeDefinition() == Globals.TypeOfKeyValue)
                     {
                         DataContract itemDataContract = DataContract.GetDataContract(Globals.TypeOfKeyValuePair.MakeGenericType(collectionDataContract.ItemType.GetGenericArguments()));
-                        knownDataContracts ??= new Dictionary<XmlQualifiedName, DataContract>();
+                        knownDataContracts ??= new DataContractDictionary();
 
                         knownDataContracts.TryAdd(itemDataContract.StableName, itemDataContract);
                     }
@@ -2040,7 +2040,7 @@ internal static void CheckAndAdd(Type type, Dictionary<Type, Type> typesChecked,
             DataContract dataContract = DataContract.GetDataContract(type);
             if (nameToDataContractTable == null)
             {
-                nameToDataContractTable = new Dictionary<XmlQualifiedName, DataContract>();
+                nameToDataContractTable = new DataContractDictionary();
             }
             else if (nameToDataContractTable.TryGetValue(dataContract.StableName, out DataContract? alreadyExistingContract))
             {
@@ -2338,7 +2338,7 @@ private XmlQualifiedName GetStableName(int i)
         }
     }
 
-    public sealed class GenericInfo : IGenericNameProvider
+    internal sealed class GenericInfo : IGenericNameProvider
     {
         private string? _genericTypeName;
         private XmlQualifiedName _stableName;

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

@@ -8,7 +8,7 @@
 using System.Runtime.CompilerServices;
 using System.Xml;
 
-using DataContractDictionary = System.Collections.Generic.IDictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
+using DataContractDictionary = System.Collections.Generic.Dictionary<System.Xml.XmlQualifiedName, System.Runtime.Serialization.DataContract>;
 
 namespace System.Runtime.Serialization
 {