#907: Enable read the untyped collection

src/Microsoft.AspNetCore.OData/Formatter/Deserialization/ODataResourceDeserializer.cs

@@ -775,6 +775,7 @@ private object ReadNestedResourceInline(ODataResourceWrapper resourceWrapper, IE
             {
                 ODataResourceWrapper resourceWrapper = CreateResourceWrapper(elementType, refLinkWrapper, readContext);
                 resourceSetWrapper.Resources.Add(resourceWrapper);
+                resourceSetWrapper.Items.Add(resourceWrapper); // in the next major release, we should only use 'Items'.
             }
 
             return resourceSetWrapper;

src/Microsoft.AspNetCore.OData/Formatter/Wrapper/ODataPrimitiveWrapper.cs

@@ -0,0 +1,31 @@
+//-----------------------------------------------------------------------------
+// <copyright file="ODataPrimitiveWrapper.cs" company=".NET Foundation">
+//      Copyright (c) .NET Foundation and Contributors. All rights reserved.
+//      See License.txt in the project root for license information.
+// </copyright>
+//------------------------------------------------------------------------------
+
+using Microsoft.OData;
+
+namespace Microsoft.AspNetCore.OData.Formatter.Wrapper
+{
+    /// <summary>
+    /// Encapsulates <see cref="ODataPrimitiveValue"/> in an Untyped (declared or undeclared) collection.
+    /// </summary>
+    public class ODataPrimitiveWrapper : ODataItemWrapper
+    {
+        /// <summary>
+        /// Initializes a new instance of <see cref="ODataPrimitiveWrapper"/>.
+        /// </summary>
+        /// <param name="value">The wrapped primitive value.</param>
+        public ODataPrimitiveWrapper(ODataPrimitiveValue value)
+        {
+            Value = value ?? throw Error.ArgumentNull(nameof(value));
+        }
+
+        /// <summary>
+        /// Gets the wrapped <see cref="ODataPrimitiveValue"/>.
+        /// </summary>
+        public ODataPrimitiveValue Value { get; }
+    }
+}

src/Microsoft.AspNetCore.OData/Formatter/Wrapper/ODataReaderExtensions.cs

@@ -5,7 +5,6 @@
 // </copyright>
 //------------------------------------------------------------------------------
 
-using System;
 using System.Collections.Generic;
 using System.Diagnostics.Contracts;
 using System.Threading.Tasks;
@@ -191,6 +190,16 @@ private static void ReadODataItem(ODataReader reader, Stack<ODataItemWrapper> it
                     linkResourceSetWrapper.DeltaItems.Add(linkBaseWrapper);
                     break;
 
+                case ODataReaderState.Primitive:
+                    Contract.Assert(itemsStack.Count > 0, "The primitive should be a non-null primitive value within an untyped collection.");
+                    // Be noted:
+                    // 1) if a 'null' value or a resource/object in the untyped collection goes to ODataResource flow
+                    // 2) if a collection value in the untyped collection goes to ODataResourceSet flow
+                    // 3) Since it's untyped, there's no logic for 'Enum' value, it means it's treated as primitive value.
+                    ODataResourceSetWrapper resourceSetParentWrapper = (ODataResourceSetWrapper)itemsStack.Peek();
+                    resourceSetParentWrapper.Items.Add(new ODataPrimitiveWrapper((ODataPrimitiveValue)reader.Item));
+                    break;
+
                 default:
                     Contract.Assert(false, "We should never get here, it means the ODataReader reported a wrong state.");
                     break;
@@ -229,6 +238,7 @@ private static void ReadResource(ODataReader reader, Stack<ODataItemWrapper> ite
                 if (parentResourceSet != null)
                 {
                     parentResourceSet.Resources.Add(resourceWrapper);
+                    parentResourceSet.Items.Add(resourceWrapper);// in the next major release, we should only use 'Items'.
                 }
                 else if (parentDeleteResourceSet != null)
                 {
@@ -301,11 +311,18 @@ private static void ReadResourceSet(ODataReader reader, Stack<ODataItemWrapper>
             ODataResourceSetWrapper resourceSetWrapper = new ODataResourceSetWrapper(resourceSet);
             if (itemsStack.Count > 0)
             {
-                ODataNestedResourceInfoWrapper parentNestedResourceInfo = (ODataNestedResourceInfoWrapper)itemsStack.Peek();
-                Contract.Assert(parentNestedResourceInfo != null, "this has to be an inner resource set. inner resource sets always have a nested resource info.");
-                Contract.Assert(parentNestedResourceInfo.NestedResourceInfo.IsCollection == true, "Only collection nested properties can contain resource set as their child.");
-                Contract.Assert(parentNestedResourceInfo.NestedItems.Count == 0, "Each nested property can contain only one resource set as its direct child.");
-                parentNestedResourceInfo.NestedItems.Add(resourceSetWrapper);
+                ODataItemWrapper peekedWrapper = itemsStack.Peek();
+                if (peekedWrapper is ODataNestedResourceInfoWrapper parentNestedResourceInfo)
+                {
+                    Contract.Assert(parentNestedResourceInfo.NestedResourceInfo.IsCollection == true, "Only collection nested properties can contain resource set as their child.");
+                    Contract.Assert(parentNestedResourceInfo.NestedItems.Count == 0, "Each nested property can contain only one resource set as its direct child.");
+                    parentNestedResourceInfo.NestedItems.Add(resourceSetWrapper);
+                }
+                else
+                {
+                    ODataResourceSetWrapper parentResourceSet = (ODataResourceSetWrapper)peekedWrapper;
+                    parentResourceSet.Items.Add(resourceSetWrapper);
+                }
             }
             else
             {

src/Microsoft.AspNetCore.OData/Formatter/Wrapper/ODataResourceSetWrapper.cs

@@ -22,6 +22,7 @@ public sealed class ODataResourceSetWrapper : ODataResourceSetBaseWrapper
         public ODataResourceSetWrapper(ODataResourceSet resourceSet)
         {
             Resources = new List<ODataResourceWrapper>();
+            Items = new List<ODataItemWrapper>();
             ResourceSet = resourceSet;
         }
 
@@ -35,5 +36,14 @@ public ODataResourceSetWrapper(ODataResourceSet resourceSet)
         /// Resource set only contains resources.
         /// </summary>
         public IList<ODataResourceWrapper> Resources { get; }
+
+        /// <summary>
+        /// Gets the nested items of this ResourceSet.
+        /// Since we have 'Resources' to contain ODataResource items in the collection (we have to keep it avoid breaking changes).
+        /// This list is used to hold other items also, for example a primitive or a collection, etc.
+        /// I assume the order of items does matter, so 'Items' contains all 'Resources' item to keep the same order.
+        /// In the next major release, we should combine 'Resources' and 'Items' together.
+        /// </summary>
+        public IList<ODataItemWrapper> Items { get; }
     }
 }

src/Microsoft.AspNetCore.OData/Microsoft.AspNetCore.OData.xml

@@ -5884,6 +5884,22 @@
             Gets the nested items that are part of this nested resource info.
             </summary>
         </member>
+        <member name="T:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper">
+            <summary>
+            Encapsulates <see cref="T:Microsoft.OData.ODataPrimitiveValue"/> in an Untyped (declared or undeclared) collection.
+            </summary>
+        </member>
+        <member name="M:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper.#ctor(Microsoft.OData.ODataPrimitiveValue)">
+            <summary>
+            Initializes a new instance of <see cref="T:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper"/>.
+            </summary>
+            <param name="value">The wrapped primitive value.</param>
+        </member>
+        <member name="P:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper.Value">
+            <summary>
+            Gets the wrapped <see cref="T:Microsoft.OData.ODataPrimitiveValue"/>.
+            </summary>
+        </member>
         <member name="T:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataReaderExtensions">
             <summary>
             Extension methods for <see cref="T:Microsoft.OData.ODataReader"/>.
@@ -5969,6 +5985,15 @@
             Resource set only contains resources.
             </summary>
         </member>
+        <member name="P:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetWrapper.Items">
+            <summary>
+            Gets the nested items of this ResourceSet.
+            Since we have 'Resources' to contain ODataResource items in the collection (we have to keep it avoid breaking changes).
+            This list is used to hold other items also, for example a primitive or a collection, etc.
+            I assume the order of items does matter, so 'Items' contains all 'Resources' item to keep the same order.
+            In the next major release, we should combine 'Resources' and 'Items' together.
+            </summary>
+        </member>
         <member name="T:Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceWrapper">
             <summary>
             Encapsulates an <see cref="T:Microsoft.OData.ODataResource"/>.

src/Microsoft.AspNetCore.OData/PublicAPI.Unshipped.txt

@@ -626,10 +626,14 @@ Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataNestedResourceInfoWrapper
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataNestedResourceInfoWrapper.NestedItems.get -> System.Collections.Generic.IList<Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataItemWrapper>
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataNestedResourceInfoWrapper.NestedResourceInfo.get -> Microsoft.OData.ODataNestedResourceInfo
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataNestedResourceInfoWrapper.ODataNestedResourceInfoWrapper(Microsoft.OData.ODataNestedResourceInfo nestedInfo) -> void
+Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper
+Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper.ODataPrimitiveWrapper(Microsoft.OData.ODataPrimitiveValue value) -> void
+Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataPrimitiveWrapper.Value.get -> Microsoft.OData.ODataPrimitiveValue
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataReaderExtensions
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetBaseWrapper
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetBaseWrapper.ODataResourceSetBaseWrapper() -> void
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetWrapper
+Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetWrapper.Items.get -> System.Collections.Generic.IList<Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataItemWrapper>
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetWrapper.ODataResourceSetWrapper(Microsoft.OData.ODataResourceSet resourceSet) -> void
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetWrapper.Resources.get -> System.Collections.Generic.IList<Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceWrapper>
 Microsoft.AspNetCore.OData.Formatter.Wrapper.ODataResourceSetWrapper.ResourceSet.get -> Microsoft.OData.ODataResourceSet

test/Microsoft.AspNetCore.OData.Tests/Formatter/Wrapper/ODataPrimitiveWrapperTests.cs

@@ -0,0 +1,37 @@
+//-----------------------------------------------------------------------------
+// <copyright file="ODataPrimitiveWrapperTests.cs" company=".NET Foundation">
+//      Copyright (c) .NET Foundation and Contributors. All rights reserved.
+//      See License.txt in the project root for license information.
+// </copyright>
+//------------------------------------------------------------------------------
+
+using Microsoft.AspNetCore.OData.Formatter.Wrapper;
+using Microsoft.AspNetCore.OData.Tests.Commons;
+using Microsoft.OData;
+using Xunit;
+
+namespace Microsoft.AspNetCore.OData.Tests.Formatter.Wrapper
+{
+    public class ODataPrimitiveWrapperTests
+    {
+        [Fact]
+        public void Ctor_ThrowsArgumentNull_PrimitiveValue()
+        {
+            // Arrange & Act & Assert
+            ExceptionAssert.ThrowsArgumentNull(() => new ODataPrimitiveWrapper(null), "value");
+        }
+
+        [Fact]
+        public void Ctor_Sets_CorrectProperties()
+        {
+            // Arrange & Act & Assert
+            ODataPrimitiveValue oDataPrimitiveValue = new ODataPrimitiveValue(42);
+
+            // Act
+            ODataPrimitiveWrapper wrapper = new ODataPrimitiveWrapper(oDataPrimitiveValue);
+
+            // Assert
+            Assert.Same(oDataPrimitiveValue, wrapper.Value);
+        }
+    }
+}