Tratando erro pra sga_name já definido no arquivo de configuração [SOMA-3827][SOMA-4074]

sga/configuration.lua

@@ -26,24 +26,20 @@ local function get_from_multiple(filename, sga_name, config)
    if not sga_name then
       return nil, string.format(err, filename, "missing sga_name argument")
    end
-
-   if config.sga_name then
-    -- TODO: Dar erro se config default tiver sga_name
-      config.sga_name = nil
-   end
-
    local config_data = config.sga[sga_name]
    if not config_data then
       return nil, string.format(err, filename, "'"..sga_name.."' not found")
    end
    config.sga = nil -- avoid multiple inside multiple
-
+   
    config, err = get(config_data, filename, config)
    if not config then
       return nil, string.format("[%s] %s", sga_name, err)
    end
+   if config.sga_name then
+      return nil, string.format("sga_name '"..config.sga_name.."' already defined in configuration file "..filename)
+   end
 
-   -- TODO: Dar erro se config do sga escolhido tiver sga_name
    config.sga_name = sga_name
 
    return config