Module:Resolve category redirect/sandbox

Resolves a soft category redirect.

It takes one parameter, which is the name of a category. It returns that category name, unless the category exists and is a {{category redirect}} ... when it returns the name of the redirect target.

Usage

{{Resolve category redirect|categoryname}}

Examples

Category exists and is not redirected

Category:1970s

• {{Resolve category redirect|1970s}} → 1970s
• {{Resolve category redirect|Category:1970s}} → Category:1970s

Category exists and is a soft redirect

Category:Mosques completed in the 19th century

• {{Resolve category redirect|Mosques completed in the 19th century}} → Mosques completed in the 19th century
• {{Resolve category redirect|Category:Mosques completed in the 19th century}} → Category:Mosques completed in the 19th century

Category exists and is a soft redirect

Category:Organisations

• {{Resolve category redirect|Organisations}} → Organisations
• {{Resolve category redirect|Category:Organisations}} → Category:Organisations

Non-existent category

Category:Colourless green things

• {{Resolve category redirect|Colourless green things}} → Colourless green things
• {{Resolve category redirect|Category:Colourless green things}} → Category:Colourless green things

Templates

Do not use templates in the target name.

{{Resolve category redirect}} cannot expand any templates in the target name, and the { character caused crashes (as did } and !). So it does not attempt to resolve any redirect where the target includes those characters.

Example

• Category:1781 in Mexico‎ contained {{category redirect|{{title year}} in New Spain}} which cannot be resolved. To be safe, {{Resolve category redirect|1781 in Mexico‎}} simply returned 1781 in Mexico‎.
  The above example has since been WIKI.org/w/index.php?title=Category:1781_in_Mexico&diff=prev&oldid=1160597791 changed to {{category redirect|1781 in New Spain}}, which can be resolved.

Avoiding deletion of the redirected page

If the parameter |keep=yes is included in the category redirect, this hides a speedy deletion button that is otherwise displayed to administrators.

It is helpful to also add {{R from category navigation}} to indicate that the redirect is required for navigation between category pages. See that template page for full syntax.

See also

• Template:Category redirect

---

local p = {}

--Returns the target of {{Category redirect}}, if it exists, else returns the original cat.
function p.rtarget( cat )
	if (mw.ustring.match( cat, '[{}!|]') ~= nil ) then
		return cat	
	end
	local catcontent = mw.title.new( cat or '', 'Category' ):getContent()
	if string.match( catcontent or '', '{{ *[Cc]at' ) then
		local getRegex = require('Module:Template redirect regex').main
		local tregex = getRegex('Category redirect')
		for _, v in pairs (tregex) do
			local rtarget = mw.ustring.match( catcontent, v..'%s*|%s*([^|{}}]+)' )
			if rtarget then
				rtarget = mw.ustring.gsub(rtarget, '^1%s*=%s*', '')
				rtarget = string.gsub(rtarget, '^[Cc]ategory:', '')
				return rtarget
			end
		end
	end
	return cat
end

function p.main( frame )
	local args = frame:getParent().args
	local cat  = args[1]
	
	if (cat == '') or (cat == nil) then
		return ''
	end
	return p.rtarget( cat )
end

return p