Module:Redirect hatnote

 --[[
 -- This module produces a "redirect" hatnote. It looks like this:
 -- '"X" redirects here. For other uses, see Y.'
 -- It implements the {{redirect}} template.
 --]]

 localmHatnote=require('Module:Hatnote')
 localmHatList=require('Module:Hatnote list')
 localmArguments--lazily initialize
 locallibraryUtil=require('libraryUtil')
 localcheckType=libraryUtil.checkType
 localcheckTypeMulti=libraryUtil.checkTypeMulti

 localp={}

 --------------------------------------------------------------------------------
 -- Helper functions
 --------------------------------------------------------------------------------

 localfunctiongetTitle(...)
 --Calls mw.title.new and returns either a title object, or nil on error
 localsuccess,titleObj=pcall(mw.title.new,...)
 returnsuccessandtitleObjornil
 end

 --------------------------------------------------------------------------------
 -- Main functions
 --------------------------------------------------------------------------------

 functionp.redirect(frame)
 mArguments=require('Module:Arguments')
 localargs=mArguments.getArgs(frame,{parentOnly=true})
 --Get number of redirects
 localnumRedirects=tonumber(frame.args[1])or1
 -- Create the options table.
 localoptions={}
 options.selfref=args.selfref
 returnp._redirect(args,numRedirects,options)
 end

 functionp._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=numRedirectsor1
 checkType('_redirect',3,options,'table',true)
 options=optionsor{}
 currentTitle=currentTitleormw.title.getCurrentTitle()
 -- Get the table of redirects
 localredirect={}
 fori=1,numRedirectsdo
 -- Return an error if a redirect parameter is missing.
 ifnotargs[i]then
 returnmHatnote.makeWikitextError(
 'missing redirect parameter',
 'Template:Redirect#Errors',
 args.category
 )
 end
 redirect[i]=args[i]
 end
 -- Generate the text.
 localformattedRedirect={}
 fork,vinpairs(redirect)do
 formattedRedirect[k]=mHatnote.quote(v)
 end
 localtext={
 mHatList.andList(formattedRedirect)..' '..(#redirect==1and'redirects'or'redirect')..' here.',
 mHatList._forSee(args,#redirect+1,{title=redirect[1],extratext=args.text})
 }
 text=table.concat(text,' ')
 -- Functionality for adding categories	
 localcategoryTable={}
 localfunctionaddCategory(cat)
 ifcatandcat~=''then
 -- Add by index to avoid duplicates
 categoryTable[string.format('[[Category:%s]]',cat)]=true
 end
 end
 --Generate tracking categories
 localmhOptions={}
 localredirTitle
 fork,vinpairs(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.
 ifnotv:find('^REDIRECT%d*$')andv~='TERM'-- 
 andcurrentTitle.namespace==0orcurrentTitle.namespace==14
 then
 redirTitle=redirectTitleorgetTitle(v)
 ifnotredirTitleornotredirTitle.existsthen
 addCategory('Missing redirects')
 elseifnotredirTitle.isRedirectthen
 ifstring.find(redirTitle:getContent(),'#invoke:RfD')then
 addCategory('Articles with redirect hatnotes impacted by RfD')
 else
 addCategory('Articles with redirect hatnotes needing review')
 end
 else
 localtarget=targetTitleorredirTitle.redirectTarget
 iftargetandtarget~=currentTitlethen
 addCategory('Articles with redirect hatnotes needing review')
 end
 end
 end

 -- Generate the options to pass to [[Module:Hatnote]].
 ifcurrentTitle.namespace==0andnotmhOptions.selfref
 andredirTitleandredirTitle.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
 localcategory=''
 fork,vinpairs(categoryTable)do
 category=category..k
 end

 returnmHatnote._hatnote(text,mhOptions)..category
 end

 returnp