internal override ConfigurationCommand Execute(XmlElement configurationElement)
{
if (ElementSpecification.Exists(configurationElement))
{
throw new InvalidOperationException(
$"The configuration element already exists at '{string.Join("/", ConfigurationElementSelector, ElementSpecification.Selector)}'.");
}
var undoCommand = ConfigurationCommandFactory.CreateUndoCommandForInsertion(this);
configurationElement.AppendChild(ElementSpecification.Execute(configurationElement.OwnerDocument));
return(undoCommand);
}
