Merge pull request #464 from remakeelectric/pulls/list-operations

get/set list operations and documentation

modules/luci-base/luasrc/model/uci.lua

@@ -111,7 +111,7 @@ function Cursor.get_list(self, config, section, option)
 		local val = self:get(config, section, option)
 		return ( type(val) == "table" and val or { val } )
 	end
-	return nil
+	return {}
 end
 
 function Cursor.get_first(self, conf, stype, opt, def)
@@ -139,6 +139,9 @@ end
 
 function Cursor.set_list(self, config, section, option, value)
 	if config and section and option then
+		if not value or #value == 0 then
+			return self:delete(config, section, option)
+		end
 		return self:set(
 			config, section, option,
 			( type(value) == "table" and value or { value } )

modules/luci-base/luasrc/model/uci.luadoc

@@ -88,7 +88,8 @@ Get an option or list and return values as table.
 @param config	UCI config
 @param section	UCI section name
 @param option	UCI option
-@return			UCI value
+@return		table.  If the option was not found, you will simply get
+--		an empty table.
 ]]
 
 ---[[
@@ -104,14 +105,15 @@ Get the given option from the first section with the given type.
 ]]
 
 ---[[
-Set given values as list.
+Set given values as list. Setting a list option to an empty list
+has the same effect as deleting the option.
 
 @class function
 @name Cursor.set_list
 @param config	UCI config
 @param section	UCI section name
 @param option	UCI option
-@param value		UCI value
+@param value	value or table. Raw values will become a single item table.
 @return			Boolean whether operation succeeded
 ]]