Delta does not allow UpdatableProperties to be changed

src/Microsoft.AspNet.OData.Shared/DeltaOfTStructuralType.cs

@@ -4,13 +4,11 @@
 using System;
 using System.Collections.Concurrent;
 using System.Collections.Generic;
-using System.Diagnostics;
 using System.Diagnostics.CodeAnalysis;
 using System.Diagnostics.Contracts;
 using System.Linq;
 using System.Reflection;
 using System.Runtime.CompilerServices;
-using Microsoft.AspNet.OData.Builder.Conventions.Attributes;
 using Microsoft.AspNet.OData.Common;
 using Microsoft.AspNet.OData.Formatter;
 
@@ -24,11 +22,11 @@ namespace Microsoft.AspNet.OData
     public class Delta<TStructuralType> : TypedDelta, IDelta where TStructuralType : class
     {
         // cache property accessors for this type and all its derived types.
-        private static ConcurrentDictionary<Type, Dictionary<string, PropertyAccessor<TStructuralType>>> _propertyCache
+        private static readonly ConcurrentDictionary<Type, Dictionary<string, PropertyAccessor<TStructuralType>>> _propertyCache
             = new ConcurrentDictionary<Type, Dictionary<string, PropertyAccessor<TStructuralType>>>();
 
         private Dictionary<string, PropertyAccessor<TStructuralType>> _allProperties;
-        private HashSet<string> _updatableProperties;
+        private List<string> _updatableProperties;
 
         private HashSet<string> _changedProperties;
 
@@ -38,7 +36,7 @@ private static ConcurrentDictionary<Type, Dictionary<string, PropertyAccessor<TS
         private TStructuralType _instance;
         private Type _structuredType;
 
-        private PropertyInfo _dynamicDictionaryPropertyinfo;
+        private readonly PropertyInfo _dynamicDictionaryPropertyinfo;
         private HashSet<string> _changedDynamicProperties;
         private IDictionary<string, object> _dynamicDictionaryCache;
 
@@ -94,18 +92,19 @@ public Delta(Type structuralType, IEnumerable<string> updatableProperties,
 
         /// <inheritdoc/>
         public override Type StructuredType
-        {
-            get
-            {
-                return _structuredType;
-            }
-        }
+            => _structuredType;
 
         /// <inheritdoc/>
         public override Type ExpectedClrType
-        {
-            get { return typeof(TStructuralType); }
-        }
+            => typeof(TStructuralType);
+
+        /// <summary>
+        /// The list of property names that can be updated.
+        /// </summary>
+        /// <remarks>When the list is modified, any modified properties that were removed from the list are no longer
+        /// considered to be changed.</remarks>
+        public IList<string> UpdatableProperties
+            => _updatableProperties;
 
         /// <inheritdoc/>
         public override void Clear()
@@ -116,7 +115,7 @@ public override void Clear()
         /// <inheritdoc/>
         public override bool TrySetPropertyValue(string name, object value)
         {
-            if (string.IsNullOrWhiteSpace(name))
+            if (String.IsNullOrWhiteSpace(name))
             {
                 throw Error.ArgumentNull("name");
             }
@@ -171,7 +170,7 @@ public override bool TryGetPropertyValue(string name, out object value)
                 }
             }
 
-            if (this._deltaNestedResources.ContainsKey(name))
+            if (_deltaNestedResources.ContainsKey(name))
             {
                 // If this is a nested resource, get the value from the dictionary of nested resources.
                 object deltaNestedResource = _deltaNestedResources[name];
@@ -259,7 +258,7 @@ public TStructuralType GetInstance()
         /// </summary>
         public override IEnumerable<string> GetChangedPropertyNames()
         {
-            return _changedProperties.Concat(_deltaNestedResources.Keys);
+            return _changedProperties.Intersect(_updatableProperties).Concat(_deltaNestedResources.Keys);
         }
 
         /// <summary>
@@ -269,7 +268,8 @@ public override IEnumerable<string> GetChangedPropertyNames()
         /// </summary>
         public override IEnumerable<string> GetUnchangedPropertyNames()
         {
-            return _updatableProperties.Except(GetChangedPropertyNames());
+            // UpdatableProperties could include arbitrary strings, filter by _allProperties
+            return _updatableProperties.Intersect(_allProperties.Keys).Except(GetChangedPropertyNames());
         }
 
         /// <summary>
@@ -295,7 +295,7 @@ public void CopyChangedValues(TStructuralType original)
 
             // For regular non-structural properties at current level.
             PropertyAccessor<TStructuralType>[] propertiesToCopy =
-                this._changedProperties.Select(s => _allProperties[s]).ToArray();
+                _changedProperties.Intersect(_updatableProperties).Select(s => _allProperties[s]).ToArray();
             foreach (PropertyAccessor<TStructuralType> propertyToCopy in propertiesToCopy)
             {
                 propertyToCopy.Copy(_instance, original);
@@ -505,12 +505,11 @@ private void InitializeProperties(IEnumerable<string> updatableProperties)
 
             if (updatableProperties != null)
             {
-                _updatableProperties = new HashSet<string>(updatableProperties);
-                _updatableProperties.IntersectWith(_allProperties.Keys);
+                _updatableProperties = updatableProperties.Intersect(_allProperties.Keys).ToList();
             }
             else
             {
-                _updatableProperties = new HashSet<string>(_allProperties.Keys);
+                _updatableProperties = new List<string>(_allProperties.Keys);
             }
 
             if (_dynamicDictionaryPropertyinfo != null)
@@ -625,7 +624,7 @@ private bool TrySetPropertyValueInternal(string name, object value)
                 throw Error.ArgumentNull("name");
             }
 
-            if (!_updatableProperties.Contains(name))
+            if (!(_allProperties.ContainsKey(name) && _updatableProperties.Contains(name)))
             {
                 return false;
             }
@@ -655,7 +654,7 @@ private bool TrySetNestedResourceInternal(string name, object deltaNestedResourc
                 throw Error.ArgumentNull("name");
             }
 
-            if (!_updatableProperties.Contains(name))
+            if (!(_allProperties.ContainsKey(name) && _updatableProperties.Contains(name)))
             {
                 return false;
             }