I am sure all fellow developers have faced the frustrating problem of not being able to insert certain objects when importing an XPO or comparing different models, layers. Today I will show you how can you insert the Table Delete actions in code compare window for AX 2012 R3.

Modify \Classes\SysTreeNode\mergeInsertSubnode method in the AOT as per below:

public void mergeInsertSubnode(
    SysComparable             _topComparable,
    SysCompareContextProvider _context,
    SysComparable               _nodeToInsert)
{
    TreeNode previousSourceNode, previousNode;
    TreeNode sourceNode;
    boolean result;
    TreeNode parentNodeInAot;
    SysTreeNode nodeToInsert;
    TreeNode    tnDeleteAction;
    #Properties
    ;
    nodeToInsert = _nodeToInsert as SysTreeNode;

    if (_nodeToInsert &&
        treeNode &&
        TreeNode::isNodeReferenceValid(treeNode))
    {
        parentNodeInAot = TreeNode::findNode(SysTreeNode::getPath(treeNode));
        if (parentNodeInAot)
        {
            sourceNode = nodeToInsert.parmTreeNode();
            previousSourceNode = sourceNode.AOTprevious();

            while (!previousNode && previousSourceNode)
            {
                previousNode       = parentNodeInAot.AOTfindChild(previousSourceNode.treeNodeName());
                previousSourceNode = previousSourceNode.AOTprevious();
            }

            // We get here e.g. if treeNode is the form design node. If previousNode=Null node is inserted last, it should be first.
            if (!previousNode)
            {
                previousNode = parentNodeInAot;
            }

            if (strScan(sourceNode.treeNodePath(), 'DeleteActions', 1, strLen(sourceNode.treeNodePath())))
            {
                tnDeleteAction = parentNodeInAot.AOTadd('UNKNOWN');
                tnDeleteAction.AOTsetProperty(#PropertyTable, sourceNode.AOTgetProperty(#PropertyTable));
                tnDeleteAction.AOTsetProperty(#PropertyDeleteAction, sourceNode.AOTgetProperty(#PropertyDeleteAction));
                tnDeleteAction.AOTsetProperty(#PropertyRelation, sourceNode.AOTgetProperty(#PropertyRelation));
                tnDeleteAction.AOTsave();
                result = true;
            }
            else
            {
                result = parentNodeInAot.AOTDrop(sourceNode, previousNode);
            }

            if (result)
            {
                // node was successfully dropped
                previousSourceNode = null;
                previousNode       = null;
                sourceNode         = null;

                //Clear cached information
                comparableTextList = null;

                treeNode = parentNodeInAot;
            }
        }
    }
}

Also you may want to make sure you have a better range of what objects can you insert, by changing \Classes\SysCompare\selectionChanged method, and adding the following to line 161:

            }

            allowInsert = true;

            this.compare(text1,
                         text2,

You can use similar logic to expand AX’s capabilities where it lacks the tools out of the box (indexes, field groups, etc.) similar to what we have done for the Table Delete actions in code compare window.