public static InterfaceDeclarationSyntax AddPropertyIfNotExists(this InterfaceDeclarationSyntax node,
string typeName,
string identifier)
{
var stateProperty = node.DescendantNodes().OfType <PropertyDeclarationSyntax>()
.FirstOrDefault(p => p.Type.ToString() == typeName);
if (stateProperty == null)
{
node = node.AddProperty(typeName, identifier);
}
return(node);
}
