HqlSqlWalker.cs: Remove use of the ASTNode.NextSibling setter, since its name doesn't give clear indication of semantics. And in practice it was the wrong semantics for the current users. See NH-3624.

Author: oskarb

src/NHibernate/Hql/Ast/ANTLR/HqlSqlWalker.cs

@@ -229,9 +229,7 @@ void PrepareVersioned(IASTNode updateNode, IASTNode versioned)
 				EvaluateAssignment(eq, persister, 0);
 
 				IASTNode setClause = updateStatement.SetClause;
-				IASTNode currentFirstSetElement = setClause.GetFirstChild();
-				setClause.SetFirstChild(eq);
-				eq.NextSibling= currentFirstSetElement;
+				setClause.InsertChild(0, eq);
 			}
 		}
 
@@ -296,9 +294,7 @@ void PostProcessInsert(IASTNode insert)
 
 				if (idSelectExprNode != null)
 				{
-					IASTNode currentFirstSelectExprNode = selectClause.GetFirstChild();
-					selectClause.SetFirstChild(idSelectExprNode);
-					idSelectExprNode.NextSibling= currentFirstSelectExprNode;
+					selectClause.InsertChild(0, idSelectExprNode);
 
 					insertStatement.IntoClause.PrependIdColumnSpec();
 				}
@@ -343,9 +339,7 @@ void PostProcessInsert(IASTNode insert)
 					}
 				}
 
-				IASTNode currentFirstSelectExprNode = selectClause.GetFirstChild();
-				selectClause.SetFirstChild(versionValueNode);
-				versionValueNode.NextSibling = currentFirstSelectExprNode;
+				selectClause.InsertChild(0, versionValueNode);
 
 				insertStatement.IntoClause.PrependVersionColumnSpec();
 			}

src/NHibernate/Hql/Ast/ANTLR/Tree/ASTNode.cs

@@ -260,24 +260,27 @@ public IASTNode NextSibling
 
 				return null;
 			}
-			set
-			{
-				if (_parent != null)
-				{
-					if (_parent.ChildCount > (ChildIndex + 1))
-					{
-						_parent.SetChild(ChildIndex + 1, value);
-					}
-					else
-					{
-						AddSibling(value);
-					}
-				}
-				else
-				{
-					throw new InvalidOperationException("Trying set NextSibling without a parent.");
-				}
-			}
+            // Setter commented out 2014-07-26. I don't like it since it drops the current next sibling from
+            // the tree, and the name of the property doesn't give a clear indication if it overwrites or not.
+            // Better to use InsertChild() on the parent.
+			//set
+			//{
+			//    if (_parent != null)
+			//    {
+			//        if (_parent.ChildCount > (ChildIndex + 1))
+			//        {
+			//            _parent.SetChild(ChildIndex + 1, value);
+			//        }
+			//        else
+			//        {
+			//            AddSibling(value);
+			//        }
+			//    }
+			//    else
+			//    {
+			//        throw new InvalidOperationException("Trying set NextSibling without a parent.");
+			//    }
+			//}
 		}
 
 		public IASTNode GetChild(int index)

src/NHibernate/Hql/Ast/ANTLR/Tree/IASTNode.cs

@@ -15,7 +15,7 @@ public interface IASTNode : IEnumerable<IASTNode>
 		int ChildCount { get; }
 		int ChildIndex { get; }
 		IASTNode Parent { get; set; }
-		IASTNode NextSibling { get; set; }
+		IASTNode NextSibling { get; /*set;*/ }
 		IASTNode GetChild(int index);
 		IASTNode GetFirstChild();
 		void SetFirstChild(IASTNode newChild);