[main] Fix to #32023 - Case expressions may only be nested to level 10 when using SplitQuery() or ToList() inside projection.

src/EFCore.Relational/Query/Internal/RelationalValueConverterCompensatingExpressionVisitor.cs

@@ -46,7 +46,12 @@ protected override Expression VisitExtension(Expression extensionExpression)
         };
 
     private Expression VisitShapedQueryExpression(ShapedQueryExpression shapedQueryExpression)
-        => shapedQueryExpression.UpdateQueryExpression(Visit(shapedQueryExpression.QueryExpression));
+    {
+        var newQueryExpression = Visit(shapedQueryExpression.QueryExpression);
+        var newShaperExpression = Visit(shapedQueryExpression.ShaperExpression);
+
+        return shapedQueryExpression.Update(newQueryExpression, newShaperExpression);
+    }
 
     private Expression VisitCase(CaseExpression caseExpression)
     {

src/EFCore.Relational/Query/Internal/SqlExpressionSimplifyingExpressionVisitor.cs

@@ -39,7 +39,10 @@ protected override Expression VisitExtension(Expression extensionExpression)
     {
         if (extensionExpression is ShapedQueryExpression shapedQueryExpression)
         {
-            return shapedQueryExpression.UpdateQueryExpression(Visit(shapedQueryExpression.QueryExpression));
+            var newQueryExpression = Visit(shapedQueryExpression.QueryExpression);
+            var newShaperExpression = Visit(shapedQueryExpression.ShaperExpression);
+
+            return shapedQueryExpression.Update(newQueryExpression, newShaperExpression);
         }
 
         // Only applies to 'CASE WHEN condition...' not 'CASE operand WHEN...'

src/EFCore.Relational/Query/RelationalQueryTranslationPostprocessor.cs

@@ -69,6 +69,7 @@ private sealed class SelectExpressionMutableVerifyingExpressionVisitor : Express
 
                 case ShapedQueryExpression shapedQueryExpression:
                     Visit(shapedQueryExpression.QueryExpression);
+                    Visit(shapedQueryExpression.ShaperExpression);
                     return shapedQueryExpression;
 
                 default:

test/EFCore.Specification.Tests/Query/ComplexNavigationsCollectionsQueryTestBase.cs

@@ -2530,4 +2530,27 @@ public virtual Task Final_GroupBy_property_entity_Include_reference_multiple(boo
                     ee, aa,
                     new ExpectedInclude<Level1>(l2 => l2.OneToOne_Optional_FK1),
                     new ExpectedInclude<Level1>(l2 => l2.OneToOne_Required_FK1))));
+
+    [ConditionalTheory]
+    [MemberData(nameof(IsAsyncData))]
+    public virtual Task Project_collection_and_nested_conditional(bool async)
+        => AssertQuery(
+            async,
+            ss => ss.Set<Level1>().OrderBy(x => x.Id).Select(x => new
+            {
+                Collection = x.OneToMany_Optional1.OrderBy(xx => xx.Id).Select(xx => xx.Name).ToList(),
+                Condition = x.Id == 1
+                    ? "01"
+                    : x.Id == 2
+                        ? "02"
+                        : x.Id == 3
+                            ? "03"
+                            : null
+            }).Where(x => x.Condition == "02"),
+            assertOrder: true,
+            elementAsserter: (e, a) =>
+            {
+                AssertCollection(e.Collection, a.Collection, ordered: true);
+                AssertEqual(e.Condition, a.Condition);
+            });
 }

test/EFCore.SqlServer.FunctionalTests/Query/ComplexNavigationsCollectionsQuerySqlServerTest.cs

@@ -2978,6 +2978,30 @@ ORDER BY [l].[Name]
 """);
     }
 
+    public override async Task Project_collection_and_nested_conditional(bool async)
+    {
+        await base.Project_collection_and_nested_conditional(async);
+
+        AssertSql(
+"""
+SELECT [l].[Id], [l0].[Name], [l0].[Id], CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END
+FROM [LevelOne] AS [l]
+LEFT JOIN [LevelTwo] AS [l0] ON [l].[Id] = [l0].[OneToMany_Optional_Inverse2Id]
+WHERE CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END = N'02'
+ORDER BY [l].[Id], [l0].[Id]
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 }

test/EFCore.SqlServer.FunctionalTests/Query/ComplexNavigationsCollectionsSharedTypeQuerySqlServerTest.cs

@@ -3870,6 +3870,36 @@ ORDER BY [l].[Name]
 """);
     }
 
+    public override async Task Project_collection_and_nested_conditional(bool async)
+    {
+        await base.Project_collection_and_nested_conditional(async);
+
+        AssertSql(
+"""
+SELECT [l].[Id], [t].[Level2_Name], [t].[Id], CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END
+FROM [Level1] AS [l]
+LEFT JOIN (
+    SELECT [l0].[Level2_Name], [l0].[Id], CASE
+        WHEN [l0].[OneToOne_Required_PK_Date] IS NOT NULL AND [l0].[Level1_Required_Id] IS NOT NULL AND [l0].[OneToMany_Required_Inverse2Id] IS NOT NULL THEN [l0].[Id]
+    END AS [c], [l0].[OneToMany_Optional_Inverse2Id]
+    FROM [Level1] AS [l0]
+    WHERE [l0].[OneToOne_Required_PK_Date] IS NOT NULL AND [l0].[Level1_Required_Id] IS NOT NULL AND [l0].[OneToMany_Required_Inverse2Id] IS NOT NULL
+) AS [t] ON [l].[Id] = [t].[OneToMany_Optional_Inverse2Id]
+WHERE CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END = N'02'
+ORDER BY [l].[Id], [t].[c]
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 }

test/EFCore.SqlServer.FunctionalTests/Query/ComplexNavigationsCollectionsSplitQuerySqlServerTest.cs

@@ -4413,6 +4413,42 @@ ORDER BY [l].[Name]
 """);
     }
 
+    public override async Task Project_collection_and_nested_conditional(bool async)
+    {
+        await base.Project_collection_and_nested_conditional(async);
+
+        AssertSql(
+"""
+SELECT [l].[Id], CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END
+FROM [LevelOne] AS [l]
+WHERE CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END = N'02'
+ORDER BY [l].[Id]
+""",
+                //
+                """
+SELECT [l0].[Name], [l].[Id]
+FROM [LevelOne] AS [l]
+INNER JOIN [LevelTwo] AS [l0] ON [l].[Id] = [l0].[OneToMany_Optional_Inverse2Id]
+WHERE CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END = N'02'
+ORDER BY [l].[Id], [l0].[Id]
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 }

test/EFCore.SqlServer.FunctionalTests/Query/TemporalComplexNavigationsCollectionsQuerySqlServerTest.cs

@@ -2998,6 +2998,30 @@ ORDER BY [l].[Name]
 """);
     }
 
+    public override async Task Project_collection_and_nested_conditional(bool async)
+    {
+        await base.Project_collection_and_nested_conditional(async);
+
+        AssertSql(
+"""
+SELECT [l].[Id], [l0].[Name], [l0].[Id], CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END
+FROM [LevelOne] FOR SYSTEM_TIME AS OF '2010-01-01T00:00:00.0000000' AS [l]
+LEFT JOIN [LevelTwo] FOR SYSTEM_TIME AS OF '2010-01-01T00:00:00.0000000' AS [l0] ON [l].[Id] = [l0].[OneToMany_Optional_Inverse2Id]
+WHERE CASE
+    WHEN [l].[Id] = 1 THEN N'01'
+    WHEN [l].[Id] = 2 THEN N'02'
+    WHEN [l].[Id] = 3 THEN N'03'
+    ELSE NULL
+END = N'02'
+ORDER BY [l].[Id], [l0].[Id]
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 }