-- -- This module implements  -- -- See unit tests at Module:URL/testcases  local p = {}   local function safeUri(s) 	local success, uri = pcall(function() 		return mw.uri.new(s) 	end) 	if success then 		return uri 	end end  local function extractUrl(args) 	for name, val in pairs(args) do 		if name ~= 2 and name ~= "msg" then 			local url = name .. "=" .. val; 			url = mw.ustring.gsub(url, '^[Hh][Tt][Tt][Pp]([Ss]?):(/?)([^/])', 'http%1://%3') 			local uri = safeUri(url); 			if uri and uri.host then 				return url 			end 		end 	end end  function p._url(url, text, msg) 	url = mw.text.trim(url or ) 	text = mw.text.trim(text or ) 	local nomsg = (msg or ):sub(1,1):lower() == "n" or msg == 'false' -- boolean: true if msg is "false" or starts with n or N  	if url ==  then 		if text ==  then 			if nomsg then 				return nil 			else 				return mw.getCurrentFrame():expandTemplate{ title = 'tlx', args = { 'URL', "example.com", "প্রদর্শনের জন্য ঐচ্ছিক লেখা" } } 			end 		else 			return text 		end 	end  	-- If the URL contains any unencoded spaces, encode them, because MediaWiki will otherwise interpret a space as the end of the URL. 	url = mw.ustring.gsub(url, '%s', function(s) return mw.uri.encode(s, 'PATH') end)  	-- If there is an empty query string or fragment id, remove it as it will cause mw.uri.new to throw an error 	url = mw.ustring.gsub(url, '#$', ) 	url = mw.ustring.gsub(url, '%?$', )  	-- If it's an HTTP[S] URL without the double slash, fix it. 	url = mw.ustring.gsub(url, '^[Hh][Tt][Tt][Pp]([Ss]?):(/?)([^/])', 'http%1://%3')  	local uri = safeUri(url)  	-- Handle URL's without a protocol and URL's that are protocol-relative,  	-- e.g. www.example.com/foo or www.example.com:8080/foo, and //www.example.com/foo 	if uri and (not uri.protocol or (uri.protocol and not uri.host)) and url:sub(1, 2) ~= '//' then 		url = 'http://' .. url 		uri = safeUri(url) 	end  	if text ==  then 		if uri then 			if uri.path == '/' then uri.path =  end  			local port =  			if uri.port then port = ':' .. uri.port end  			text = mw.ustring.lower(uri.host or ) .. port .. (uri.relativePath or )  			-- Add  before _/.-# sequences 			text = mw.ustring.gsub(text,"(/+)","%1")      -- This entry MUST be the first. "" has a "/" in it, you know. 			text = mw.ustring.gsub(text,"(%.+)","%1") 			-- text = mw.ustring.gsub(text,"(%-+)","%1") 	-- DISABLED for now 			text = mw.ustring.gsub(text,"(%#+)","%1") 			text = mw.ustring.gsub(text,"(_+)","%1") 		else -- URL is badly-formed, so just display whatever was passed in 			text = url 		end 	end  	return mw.ustring.format('[%s %s]', url, text) end  --[[ The main entry point for calling from Template:URL. --]] function p.url(frame) 	local templateArgs = frame.args 	local parentArgs = frame:getParent().args 	local url = templateArgs[1] or parentArgs[1] 	local text = templateArgs[2] or parentArgs[2] or 	local msg = templateArgs.msg or parentArgs.msg or  	url = url or extractUrl(templateArgs) or extractUrl(parentArgs) or 	return p._url(url, text, msg) end  --[[ The entry point for calling from the forked Template:URL2. This function returns no message by default. It strips out wiki-link markup, html tags, and everything after a space. --]] function p.url2(frame) 	local templateArgs = frame.args 	local parentArgs = frame:getParent().args 	local url = templateArgs[1] or parentArgs[1] 	local text = templateArgs[2] or parentArgs[2] or  	-- default to no message 	local msg = templateArgs.msg or parentArgs.msg or 'no' 	url = url or extractUrl(templateArgs) or extractUrl(parentArgs) or 	-- if the url came from a Wikidata call, it might have a pen icon appended 	-- we want to keep that and add it back at the end. 	local u1, penicon = mw.ustring.match( url, "(.*)( <span class='penicon.*)" ) 	if penicon then url = u1 end 	-- strip out html tags and [ ] from url 	url = (url or ):gsub("<[^>]*>", ""):gsub("[%[%]]", "") 	-- truncate anything after a space 	url = url:gsub("%%20", " "):gsub(" .*", "") 	return (p._url(url, text, msg) or "") .. (penicon or "") end  return p