Handle shadow navigations when loading with split queries

Fixes #32225

src/EFCore.Relational/Query/RelationalShapedQueryCompilingExpressionVisitor.ShaperProcessingExpressionVisitor.ClientMethods.cs

@@ -327,7 +327,7 @@ private static void InitializeSplitIncludeCollection<TParent, TNavigationEntity>
             TParent entity,
             Func<QueryContext, DbDataReader, object[]> parentIdentifier,
             INavigationBase navigation,
-            IClrCollectionAccessor clrCollectionAccessor,
+            IClrCollectionAccessor? clrCollectionAccessor,
             bool trackingQuery,
             bool setLoaded)
             where TParent : class
@@ -348,7 +348,7 @@ private static void InitializeSplitIncludeCollection<TParent, TNavigationEntity>
                     }
                 }
 
-                collection = clrCollectionAccessor.GetOrCreate(entity, forMaterialization: true);
+                collection = clrCollectionAccessor?.GetOrCreate(entity, forMaterialization: true);
             }
 
             var parentKey = parentIdentifier(queryContext, parentDataReader);

src/EFCore/Metadata/Internal/ClrCollectionAccessor.cs

@@ -17,6 +17,7 @@ public class ClrICollectionAccessor<TEntity, TCollection, TElement> : IClrCollec
     where TElement : class
 {
     private readonly string _propertyName;
+    private readonly bool _shadow;
     private readonly Func<TEntity, TCollection>? _getCollection;
     private readonly Action<TEntity, TCollection>? _setCollection;
     private readonly Action<TEntity, TCollection>? _setCollectionForMaterialization;
@@ -40,13 +41,15 @@ public virtual Type CollectionType
     /// </summary>
     public ClrICollectionAccessor(
         string propertyName,
+        bool shadow,
         Func<TEntity, TCollection>? getCollection,
         Action<TEntity, TCollection>? setCollection,
         Action<TEntity, TCollection>? setCollectionForMaterialization,
         Func<TEntity, Action<TEntity, TCollection>, TCollection>? createAndSetCollection,
         Func<TCollection>? createCollection)
     {
         _propertyName = propertyName;
+        _shadow = shadow;
         _getCollection = getCollection;
         _setCollection = setCollection;
         _setCollectionForMaterialization = setCollectionForMaterialization;
@@ -137,6 +140,11 @@ private ICollection<TElement> GetOrCreateCollection(object instance, bool forMat
 
     private ICollection<TElement>? GetCollection(object instance)
     {
+        if (_shadow)
+        {
+            return (ICollection<TElement>?)_createCollection?.Invoke();
+        }
+
         var enumerable = _getCollection!((TEntity)instance);
         var collection = enumerable as ICollection<TElement>;
 

src/EFCore/Metadata/Internal/ClrCollectionAccessorFactory.cs

@@ -205,6 +205,7 @@ private static IClrCollectionAccessor CreateGeneric<TEntity, TCollection, TEleme
 
         return new ClrICollectionAccessor<TEntity, TCollection, TElement>(
             navigation.Name,
+            navigation.IsShadowProperty(),
             getterDelegate,
             setterDelegate,
             setterDelegateForMaterialization,

test/EFCore.Specification.Tests/EFCore.Specification.Tests.csproj

@@ -48,6 +48,7 @@
 
   <ItemGroup>
     <ProjectReference Include="..\..\src\EFCore\EFCore.csproj" />
+    <ProjectReference Include="..\..\src\EFCore.Analyzers\EFCore.Analyzers.csproj" />
     <ProjectReference Include="..\..\src\EFCore.Design\EFCore.Design.csproj" />
     <ProjectReference Include="..\..\src\EFCore.Proxies\EFCore.Proxies.csproj" />
     <ProjectReference Include="..\..\src\EFCore.Abstractions\EFCore.Abstractions.csproj" />

test/EFCore.Sqlite.FunctionalTests/Query/ManyToManyNoTrackingSplitQuerySqliteTest.cs

@@ -0,0 +1,23 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Microsoft.EntityFrameworkCore.Sqlite.Internal;
+
+namespace Microsoft.EntityFrameworkCore.Query;
+
+public class ManyToManyNoTrackingSplitQuerySqliteTest
+    : ManyToManyNoTrackingQueryRelationalTestBase<ManyToManySplitQuerySqliteFixture>
+{
+    public ManyToManyNoTrackingSplitQuerySqliteTest(ManyToManySplitQuerySqliteFixture fixture)
+        : base(fixture)
+    {
+    }
+
+    // Sqlite does not support Apply operations
+
+    public override async Task Skip_navigation_order_by_single_or_default(bool async)
+        => Assert.Equal(
+            SqliteStrings.ApplyNotSupported,
+            (await Assert.ThrowsAsync<InvalidOperationException>(
+                () => base.Skip_navigation_order_by_single_or_default(async))).Message);
+}

test/EFCore.Sqlite.FunctionalTests/Query/ManyToManySplitQuerySqliteFixture.cs

@@ -0,0 +1,13 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+namespace Microsoft.EntityFrameworkCore.Query;
+
+public class ManyToManySplitQuerySqliteFixture : ManyToManyQuerySqliteFixture
+{
+    protected override string StoreName
+        => "ManyToManySplitQuery";
+
+    public override DbContextOptionsBuilder AddOptions(DbContextOptionsBuilder builder)
+        => base.AddOptions(builder.UseSqlite(b => b.UseQuerySplittingBehavior(QuerySplittingBehavior.SplitQuery)));
+}

test/EFCore.Sqlite.FunctionalTests/Query/ManyToManySplitQuerySqliteTest.cs

@@ -0,0 +1,20 @@
+// Licensed to the .NET Foundation under one or more agreements.
+// The .NET Foundation licenses this file to you under the MIT license.
+
+using Microsoft.EntityFrameworkCore.Sqlite.Internal;
+
+namespace Microsoft.EntityFrameworkCore.Query;
+
+public class ManyToManySplitQuerySqliteTest : ManyToManyQueryRelationalTestBase<ManyToManySplitQuerySqliteFixture>
+{
+    public ManyToManySplitQuerySqliteTest(ManyToManySplitQuerySqliteFixture fixture)
+        : base(fixture)
+    {
+    }
+
+    public override async Task Skip_navigation_order_by_single_or_default(bool async)
+        => Assert.Equal(
+            SqliteStrings.ApplyNotSupported,
+            (await Assert.ThrowsAsync<InvalidOperationException>(
+                () => base.Skip_navigation_order_by_single_or_default(async))).Message);
+}