<span class="mw-page-title-namespace">Module</span><span class="mw-page-title-separator">:</span><span class="mw-page-title-main">Check for unknown parameters</span>

This module is subject to page protection. It is a highly visible module in use by a very large number of pages, or is substituted very frequently. Because vandalism or mistakes would affect many pages, and even trivial editing might cause substantial load on the servers, it is protected from editing.

This module may be appended to a template to check for uses of unknown parameters.

Usage

Basic usage

{{#invoke:check for unknown parameters|check
|unknown=[[Category:Some tracking category]]
|arg1|arg2|arg3|argN}}

or to sort the entries in the tracking category by parameter with a preview error message

{{#invoke:check for unknown parameters|check
|unknown=[[Category:Some tracking category|_VALUE_]]
|preview=unknown parameter "_VALUE_"
|arg1|arg2|...|argN}}

or for an explicit red error message

{{#invoke:check for unknown parameters|check
|unknown=<span class="error">Sorry, I don't recognize _VALUE_</span>
|arg1|arg2|...|argN}}

Here, arg1, arg2, ..., argN, are the known parameters. Unnamed (positional) parameters can be added too: |1|2|argname1|argname2|.... Any parameter which is used, but not on this list, will cause the module to return whatever is passed with the unknown parameter. The _VALUE_ keyword, if used, will be changed to the name of the parameter. This is useful for either sorting the entries in a tracking category, or for provide more explicit information.

By default, the module makes no distinction between a defined-but-blank parameter and a non-blank parameter. That is, both unlisted |foo=x and |foo= are reported. To only track non-blank parameters use |ignoreblank=1.

By default, the module ignores blank positional parameters. That is, an unlisted |2= is ignored. To include blank positional parameters in the tracking use |showblankpositional=1.

Lua patterns

This module supports Lua patterns (similar to regular expressions), which are useful when there are many known parameters which use a systematic pattern. For example, template:infobox3cols uses

| regexp1 = header[%d][%d]*
| regexp2 = label[%d][%d]*
| regexp3 = data[%d][%d]*[abc]?
| regexp4 = class[%d][%d]*[abc]?
| regexp5 = rowclass[%d][%d]*
| regexp6 = rowstyle[%d][%d]*
| regexp7 = rowcellstyle[%d][%d]*

to match all parameters of the form headerNUM, labelNUM, dataNUM, dataNUMa, dataNUMb, dataNUMc, ..., rowcellstyleNUM, where NUM is a string of digits.

Example

{{Infobox
| above = {{{name|}}}

| label1 = Height
| data1 = {{{height|}}}

| label2 = Weight
| data2 = {{{weight|}}}

| label3 = Website
| data3 = {{{website|}}}
}}<!-- 
  end infobox, start tracking
-->{{#invoke:Check for unknown parameters|check
| unknown = {{main other|[[Category:Some tracking category|_VALUE_]]}}
| preview = unknown parameter "_VALUE_"
| name
| height | weight
| website
}}

See also

• Category:Unknown parameters (0) (category page can have header {{Unknown parameters category}})
• Module:Check for deprecated parameters – similar module that checks for deprecated parameters
• Module:Check for clobbered parameters – module that checks for conflicting parameters
• Module:TemplatePar – similar function (originally from dewiki)
• Template:Parameters and Module:Parameters – generates a list of parameter names for a given template
• Project:TemplateData based template parameter validation
• Module:Parameter validation checks a lot more
• User:Bamyers99/TemplateParametersTool - A tool for checking usage of template parameters

---

-- 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

	-- create the list of known args, regular expressions, and the return string
	local knownargs = {}
	local regexps = {}
	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

	-- loop over the parent args, and make sure they are on the list
	local ignoreblank = isnotempty(args['ignoreblank'])
	local showblankpos = isnotempty(args['showblankpositional'])
	local values = {}
	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 then
			local knownflag = false
			for _, regexp in ipairs(regexps) do
				if mw.ustring.match(tostring(k), regexp) then
					knownflag = true
					break
				end
			end
			if not knownflag and ( showblankpos or isnotempty(v) ) then
				table.insert(values, k .. ' = ' .. clean(v))
			end
		end
	end

	-- add results to the output tables
	local res = {}
	if #values > 0 then
		local unknown_text = args['unknown'] or 'Found _VALUE_, '

		if mw.getCurrentFrame():preprocess( "{{REVISIONID}}" ) == "" then
			local preview_text = args['preview']
			if isnotempty(preview_text) then
				preview_text = require('Module:If preview')._warning({preview_text})
			elseif preview == nil then
				preview_text = unknown_text
			end
			unknown_text = preview_text
		end
		for _, v in pairs(values) do
			-- Fix odd bug for | = which gets stripped to the empty string and
			-- breaks category links
			if v == '' then v = ' ' end

			-- avoid error with v = 'example%2' ("invalid capture index")
			local r = unknown_text: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