Module:Check for unknown parameters

    From Nonbinary Wiki

    Documentation for this module may be created at Module:Check for unknown parameters/doc

    -- This module may be used to compare the arguments passed to the parent
    -- with a list of arguments, returning a specified result if an argument is
    -- not on the list
    local p = {}
    
    local function trim(s)
    	return s:match('^%s*(.-)%s*$')
    end
    
    local function isnotempty(s)
    	return s and s:match('%S')
    end
    
    local function clean(text)
    	-- Return text cleaned for display and truncated if too long.
    	-- Strip markers are replaced with dummy text representing the original wikitext.
    	local pos, truncated
    	local function truncate(text)
    		if truncated then
    			return ''
    		end
    		if mw.ustring.len(text) > 25 then
    			truncated = true
    			text = mw.ustring.sub(text, 1, 25) .. '...'
    		end
    		return mw.text.nowiki(text)
    	end
    	local parts = {}
    	for before, tag, remainder in text:gmatch('([^\127]*)\127[^\127]*%-(%l+)%-[^\127]*\127()') do
    		pos = remainder
    		table.insert(parts, truncate(before) .. '<' .. tag .. '>...</' .. tag .. '>')
    	end
    	table.insert(parts, truncate(text:sub(pos or 1)))
    	return table.concat(parts)
    end
    
    function p._check(args, pargs)
    	if type(args) ~= "table" or type(pargs) ~= "table" then
    		-- TODO: error handling
    		return
    	end
    
    	local ignoreblank = isnotempty(args['ignoreblank'])
    	local showblankpos = isnotempty(args['showblankpositional'])
    	local knownargs = {}
    	local unknown = args['unknown'] or 'Found _VALUE_, '
    	local preview = args['preview']
    
    	local values = {}
    	local res = {}
    	local regexps = {}
    
    	-- create the list of known args, regular expressions, and the return string
    	for k, v in pairs(args) do
    		if type(k) == 'number' then
    			v = trim(v)
    			knownargs[v] = 1
    		elseif k:find('^regexp[1-9][0-9]*$') then
    			table.insert(regexps, '^' .. v .. '$')
    		end
    	end
    	if isnotempty(preview) then
    		preview = '<div class="hatnote" style="color:red"><strong>Warning:</strong> ' .. preview .. ' (this message is shown only in preview).</div>'
    	elseif preview == nil then
    		preview = unknown
    	end
    
    	-- loop over the parent args, and make sure they are on the list
    	for k, v in pairs(pargs) do
    		if type(k) == 'string' and knownargs[k] == nil then
    			local knownflag = false
    			for _, regexp in ipairs(regexps) do
    				if mw.ustring.match(k, regexp) then
    					knownflag = true
    					break
    				end
    			end
    			if not knownflag and ( not ignoreblank or isnotempty(v) )  then
    				table.insert(values, clean(k))
    			end
    		elseif type(k) == 'number' and
    			knownargs[tostring(k)] == nil and
    			( showblankpos or isnotempty(v) )
    		then
    			table.insert(values, k .. ' = ' .. clean(v))
    		end
    	end
    
    	-- add results to the output tables
    	if #values > 0 then
    		if mw.getCurrentFrame():preprocess( "{{REVISIONID}}" ) == "" then
    			unknown = preview
    		end
    		for _, v in pairs(values) do
    			if v == '' then
    				-- Fix odd bug for | = which gets stripped to the empty string and
    				-- breaks category links
    				v = ' '
    			end
    			-- avoid error with v = 'example%2' ("invalid capture index")
    			local r =  unknown:gsub('_VALUE_', {_VALUE_ = v})
    			table.insert(res, r)
    		end
    	end
    
    	return table.concat(res)
    end
    
    function p.check(frame)
    	local args = frame.args
    	local pargs = frame:getParent().args
    	return p._check(args, pargs)
    end
    
    return p