Add three-level-deep nested new test to exercise recursive TryRebuildMemberInitExpression

Agent-Logs-Url: https://github.com/zzzprojects/System.Linq.Dynamic.Core/sessions/42b1ec4e-90f4-484b-ae3a-73f3bee9c50b

Co-authored-by: StefH <249938+StefH@users.noreply.github.com>

Author: Copilot

test/System.Linq.Dynamic.Core.Tests/DynamicExpressionParserTests.cs

@@ -2321,13 +2321,46 @@ public void DynamicExpressionParser_ParseLambda_NestedObjectInitialization()
         result.CurrentDepartment!.Id.Should().Be(3);
     }
 
+    // https://github.com/zzzprojects/System.Linq.Dynamic.Core/issues/701
+    [Fact]
+    public void DynamicExpressionParser_ParseLambda_NestedObjectInitialization_ThreeLevelsDeep()
+    {
+        // Arrange — exercises the recursive TryRebuildMemberInitExpression path.
+        // The parser propagates _resultType (CustomerForNestedNewTest) into all nested new
+        // expressions. The middle "new (new (3 as Id) as Sub)" therefore builds a
+        // MIE<Customer>{ Sub = MIE<Department>{Id=3} }.  When the outer new binds that to its own
+        // "Sub" property (type DepartmentForNestedNewTest), TryRebuildMemberInitExpression is
+        // called and encounters the inner MIE<Department>{Id=3} binding — a MemberInitExpression
+        // itself — which triggers the recursive call to rebuild it for SubDepartmentForNestedNewTest.
+        var srcType = typeof(CustomerForNestedNewTest);
+
+        // Act
+        var lambda = DynamicExpressionParser.ParseLambda(ParsingConfig.DefaultEFCore21, srcType, srcType,
+            "new (new (new (3 as Id) as Sub) as Sub)");
+        var @delegate = lambda.Compile();
+        var result = (CustomerForNestedNewTest)@delegate.DynamicInvoke(new CustomerForNestedNewTest())!;
+
+        // Assert
+        result.Should().NotBeNull();
+        result.Sub.Should().NotBeNull();
+        result.Sub!.Sub.Should().NotBeNull();
+        result.Sub.Sub!.Id.Should().Be(3);
+    }
+
     public class CustomerForNestedNewTest
     {
         public int Id { get; set; }
         public DepartmentForNestedNewTest? CurrentDepartment { get; set; }
+        public DepartmentForNestedNewTest? Sub { get; set; }
     }
 
     public class DepartmentForNestedNewTest
+    {
+        public int Id { get; set; }
+        public SubDepartmentForNestedNewTest? Sub { get; set; }
+    }
+
+    public class SubDepartmentForNestedNewTest
     {
         public int Id { get; set; }
     }