Visit inside InlineQueryRootExpression in nav expansion

src/EFCore/Query/Internal/NavigationExpandingExpressionVisitor.cs

@@ -249,11 +249,23 @@ protected override Expression VisitExtension(Expression extensionExpression)
 
                 return ApplyQueryFilter(entityType, navigationExpansionExpression);
 
+            // Inline query roots can contain arbitrary expressions, including subqueries with navigations; visit inside to process those.
+            case InlineQueryRootExpression inlineQueryRootExpression:
+            {
+                var visited = inlineQueryRootExpression.Update(this.VisitAndConvert(inlineQueryRootExpression.Values));
+                var currentTree = new NavigationTreeExpression(Expression.Default(inlineQueryRootExpression.ElementType));
+                var parameterName = GetParameterName("e");
+
+                return new NavigationExpansionExpression(visited, currentTree, currentTree, parameterName);
+            }
+
             case QueryRootExpression queryRootExpression:
+            {
                 var currentTree = new NavigationTreeExpression(Expression.Default(queryRootExpression.ElementType));
                 var parameterName = GetParameterName("e");
 
                 return new NavigationExpansionExpression(queryRootExpression, currentTree, currentTree, parameterName);
+            }
 
             case NavigationExpansionExpression:
             case OwnedNavigationReference:

test/EFCore.Cosmos.FunctionalTests/Query/NorthwindMiscellaneousQueryCosmosTest.cs

@@ -4606,6 +4606,14 @@ await AssertTranslationFailed(
         AssertSql();
     }
 
+    public override async Task Subquery_with_navigation_inside_inline_collection(bool async)
+    {
+        await AssertTranslationFailed(
+            () => base.Subquery_with_navigation_inside_inline_collection(async));
+
+        AssertSql();
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);
 

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

@@ -5652,4 +5652,11 @@ public virtual Task Collection_navigation_equal_to_null_for_subquery_using_Eleme
             ss => ss.Set<Customer>().Where(c => c.Orders.OrderBy(o => o.OrderID).ElementAtOrDefault(prm).OrderDetails == null),
             ss => ss.Set<Customer>().Where(c => c.Orders.OrderBy(o => o.OrderID).ElementAtOrDefault(prm) == null));
     }
+
+    [ConditionalTheory]
+    [MemberData(nameof(IsAsyncData))]
+    public virtual Task Subquery_with_navigation_inside_inline_collection(bool async)
+        => AssertQuery(
+            async,
+            ss => ss.Set<Customer>().Where(c => new[] { 100, c.Orders.Count }.Sum() > 101));
 }

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

@@ -7260,6 +7260,23 @@ ORDER BY [o].[OrderID]
 """);
     }
 
+    public override async Task Subquery_with_navigation_inside_inline_collection(bool async)
+    {
+        await base.Subquery_with_navigation_inside_inline_collection(async);
+
+        AssertSql(
+            """
+SELECT [c].[CustomerID], [c].[Address], [c].[City], [c].[CompanyName], [c].[ContactName], [c].[ContactTitle], [c].[Country], [c].[Fax], [c].[Phone], [c].[PostalCode], [c].[Region]
+FROM [Customers] AS [c]
+WHERE (
+    SELECT COALESCE(SUM([v].[Value]), 0)
+    FROM (VALUES (CAST(100 AS int)), ((
+        SELECT COUNT(*)
+        FROM [Orders] AS [o]
+        WHERE [c].[CustomerID] = [o].[CustomerID]))) AS [v]([Value])) > 101
+""");
+    }
+
     private void AssertSql(params string[] expected)
         => Fixture.TestSqlLoggerFactory.AssertBaseline(expected);