[pedrozzz]

Общая идея может быть такая:

static void testFormMethod(Args _args)
{
    TreeNodePath        path = @'\Forms\SalesTable\Data Sources\SalesTable\Methods\testMethod';
    
    TreeNode            treeNodeObj;
    MemberFunction      treeNodeMethod;
    str                 source;
    #AOT
    ;

    treeNodeMethod = TreeNode::findNode(path);

    if (treeNodeMethod)
    {
        source = SysUtil::unpackSource(treeNodeMethod.AOTgetSource());

        //-->
        //Производим манипуляции с исходным кодом
        //<--

        treeNodeMethod.AOTsetSource(source);
        treeNodeMethod.AOTcompile();
        treeNodeMethod.AOTsave();

        treeNodeObj = treeNodeMethod.AOTparent();

        while (treeNodeObj.AOTparent()
           &&  treeNodeObj.AOTparent().treeNodePath() != #FormsPath)
        {
            treeNodeObj = treeNodeObj.AOTparent();
        }
    
        treeNodeObj.AOTsave();
    }
}