# Module:Redirect hatnote

---
-- This module produces a "redirect" hatnote. It looks like this:
-- '"X" redirects here. For other uses, see Y.'
-- It implements the template.
---  
local mHatnote = require('Module:Hatnote')
local mHatList = require('Module:Hatnote list')
local mArguments --lazily initialize
local libraryUtil = require('libraryUtil')
local checkType = libraryUtil.checkType
local checkTypeMulti = libraryUtil.checkTypeMulti  
local p = {}  
local function getTitle(...)
local success, titleObj = pcall(mw.title.new, ...)
if success then
return titleObj
else
return nil
end
end  
function p.redirect
mArguments = require('Module:Arguments')
local args = mArguments.getArgs(, {parentOnly=true})
--Get number of redirects
local numRedirects = tonumber(.args[1]) or 1
-- Create the options table.
local options = {}
options.selfref = args.selfref
return p._redirect(args, numRedirects, options)
end  
function p._redirect(args, numRedirects, options, currentTitle, redirectTitle, targetTitle)
-- Validate the input. Don't bother checking currentTitle, redirectTitle or
-- targetTitle, as they are only used in testing.
checkType('_redirect', 1, args, 'table')
checkType('_redirect', 2, numRedirects, 'number', true)
numRedirects = numRedirects or 1
checkType('_redirect', 3, options, 'table', true)
options = options or {}
currentTitle = currentTitle or mw.title.getCurrentTitle
-- Get the table of redirects
local redirect = {}
for i = 1, numRedirects do
-- Return an error if a redirect parameter is missing.
if not args[i] then
return mHatnote.makeWikitextError(
'missing redirect parameter',
'Template:Redirect#Errors',
args.category
end
redirect[i] = args[i]
end
-- Generate the text.
local formattedRedirect = {}
for k,v in pairs(redirect) do
formattedRedirect[k] = '"' .. v .. '"'
end
local text = {
mHatList.andList(formattedRedirect) .. ' ' .. (#redirect == 1 and 'redirects' or 'redirect') .. ' here.',
mHatList._forSee(args, #redirect + 1, {title = redirect[1]})
}
text = table.concat(text, ' ')
-- Functionality for adding categories
local categoryTable = {}
function addCategory(cat)
if cat and cat ~= '' then
-- Add by index to avoid duplicates
categoryTable[string.format('', cat)] = true
end
end
--Generate tracking categories
local mhOptions = {}
for k,v in pairs(redirect) do
-- We don't need a tracking category if the template invocation has been
-- copied directly from the docs, or if we aren't in main- or category-space.
if not v:find('^REDIRECT%d*$') and v ~= 'TERM' --
and currentTitle.namespace == 0 or currentTitle.namespace == 14
then
redirectTitle = redirectTitle or getTitle(v)
if not redirectTitle or not redirectTitle.exists then
addCategory('Missing redirects')
elseif not redirectTitle.isRedirect then
addCategory('Articles with redirect hatnotes needing review')
else
local mRedirect = require('Module:Redirect')
local target = mRedirect.getTarget(redirectTitle)
targetTitle = targetTitle or target and getTitle(target)
if targetTitle and targetTitle ~= currentTitle then
addCategory('Articles with redirect hatnotes needing review')
end
end
end  
-- Generate the options to pass to Module:Hatnote.
if currentTitle.namespace == 0 and not mhOptions.selfref
and redirectTitle and redirectTitle.namespace ~= 0
then
-- We are on a mainspace page, and the hatnote starts with something
-- like "Wikipedia:Foo redirects here", so automatically label it as
-- a self-reference.
mhOptions.selfref = true
else
mhOptions.selfref = options.selfref
end
end
--concatenate all the categories
local category = ''
for k,v in pairs(categoryTable) do
category = category .. k
end  
return mHatnote._hatnote(text, mhOptions) .. category
end  
return p