fixed that if the last is a select many it needs to check for null as well :)

PoweredSoft.DynamicLinq.Test/SelectTests.cs

@@ -97,9 +97,18 @@ namespace PoweredSoft.DynamicLinq.Test
                 t.PathToList("Posts.Comments.CommentLikes", selectCollectionHandling: SelectCollectionHandling.Flatten);
             });
 
-            var abc = querySelect.ToObjectList();
+            var b = querySelect.ToDynamicClassList();
 
-            var list = querySelect.ToDynamicClassList();
+            Assert.AreEqual(a.Count, b.Count);
+            for(var i = 0; i  < a.Count; i++)
+            {
+                var left = a[i];
+                var right = b[i];
+
+                var leftCommentLikes = left.CommentLikes;
+                var rightCommentLikes = right.GetDynamicPropertyValue<List<CommentLike>>("CommentLikes");
+                QueryableAssert.AreEqual(leftCommentLikes.AsQueryable(), rightCommentLikes.AsQueryable());
+            }
         }
     }
 }

PoweredSoft.DynamicLinq.Test/TestData.cs

@@ -133,7 +133,22 @@ namespace PoweredSoft.DynamicLinq.Test
                                 Id = 1,
                                 DisplayName = "John Doe",
                                 CommentText = "!@#$!@#!@#",
-                                Email = "john.doe@me.com"
+                                Email = "john.doe@me.com",
+                                CommentLikes = new List<CommentLike>()
+                                {
+                                    new CommentLike()
+                                    {
+                                        Id = 1,
+                                        CommentId = 1,
+                                        CreateTime = DateTimeOffset.Now
+                                    },
+                                    new CommentLike()
+                                    {
+                                        Id = 2,
+                                        CommentId = 1,
+                                        CreateTime = DateTimeOffset.Now
+                                    },
+                                }
                             }
                         }
                     },

PoweredSoft.DynamicLinq/Resolver/PathExpressionResolver.cs

@@ -62,11 +62,12 @@ namespace PoweredSoft.DynamicLinq.Resolver
                     var parentExpression = CompileGroup(parent, NullChecking);
 
                     // check null with where.
+                    var isSelectMany = CollectionHandling == SelectCollectionHandling.Flatten && QueryableHelpers.IsGenericEnumerable(groupExpression);
                     if (NullChecking != false)
-                        parentExpression = CheckNullOnEnumerableParent(group, parent, parentExpression, isLastGroup);
+                        parentExpression = CheckNullOnEnumerableParent(group, parent, parentExpression, isLastGroup && !isSelectMany);
 
                     // the select expression.
-                    if (CollectionHandling == SelectCollectionHandling.Flatten && QueryableHelpers.IsGenericEnumerable(groupExpression))
+                    if (isSelectMany)
                     {
                         var selectType = parent.GroupEnumerableType();
                         var selectExpression = Expression.Call(typeof(Enumerable), "SelectMany",
@@ -98,11 +99,11 @@ namespace PoweredSoft.DynamicLinq.Resolver
                     var parentExpression = CompileGroup(parent, NullChecking);
                     var selectType = parent.GroupEnumerableType();
 
-
+                    bool isSelectMany = CollectionHandling == SelectCollectionHandling.Flatten && QueryableHelpers.IsGenericEnumerable(currentExpression);
                     if (NullChecking != false)
-                        parentExpression = CheckNullOnEnumerableParent(group, parent, parentExpression, isLastGroup);
+                        parentExpression = CheckNullOnEnumerableParent(group, parent, parentExpression, isLastGroup && !isSelectMany);
 
-                    if (CollectionHandling == SelectCollectionHandling.Flatten && QueryableHelpers.IsGenericEnumerable(currentExpression))
+                    if (isSelectMany)
                     {
                         var currentExpressionLambda = Expression.Lambda(currentExpression, group.Parameter);
                         currentExpression = Expression.Call(typeof(Enumerable), "SelectMany",
@@ -147,10 +148,10 @@ namespace PoweredSoft.DynamicLinq.Resolver
             return Expression.Condition(whereBodyExpression, ifTrueExpression, currentExpression, currentExpression.Type);
         }
 
-        private static Expression CheckNullOnEnumerableParent(ExpressionParserPieceGroup group, ExpressionParserPieceGroup parent, Expression parentExpression, bool isLastGroup)
+        private static Expression CheckNullOnEnumerableParent(ExpressionParserPieceGroup group, ExpressionParserPieceGroup parent, Expression parentExpression, bool shouldSkipLast)
         {
             string path = null;
-            if (isLastGroup)
+            if (shouldSkipLast)
                 path = string.Join(".", group.Pieces.Take(group.Pieces.Count - 1).Select(t => t.Name));
             else
                 path = string.Join(".", group.Pieces.Select(t => t.Name));