local p = {}
local function noredir(page)
local link = page:fullUrl("redirect=no")
return "<span class=\"plainlinks\">[" .. link .. " " .. page.fullText .. "]</span>"
end
function p.main(frame)
local args = require("Module:Arguments").getArgs(frame, {removeBlanks=false})
-- Demo parameters, for demonstrating behavior with certain redirect
-- targets and avoiding categorization (do not use in articles)
local noError = args.noerror
local demo = args.demo or noError or args.thistarget or args.othertarget
local function formatError(err)
return "<span class=\"error\">Error in [[Module:R avoided double redirect]]: " .. err .. "</span>"
.. (demo and "" or "[[Category:Avoided double redirect errors]]")
end
local thisPage = mw.title.getCurrentTitle()
local otherPage = mw.title.new(args[1] or "")
if not otherPage then
return formatError("No other page was specified.");
end
if mw.title.equals(thisPage, otherPage) then
return formatError("The current page was passed as the parameter.");
end
-- Get mw.title objects for redirect targets.
-- Note that using mw.title's redirectTarget will correctly handle preview mode, unlike Module:Redirect.
local thisTarget, otherTarget
if demo and args.thistarget then
thisTarget = mw.title.new(args.thistarget)
else
thisTarget = thisPage.redirectTarget
end
if demo and args.othertarget then
otherTarget = mw.title.new(args.othertarget)
else
otherTarget = otherPage.redirectTarget
end
-- For double redirects
local thisDoubleTarget = thisTarget and thisTarget.redirectTarget
local otherDoubleTarget = otherTarget and otherTarget.redirectTarget
local function formatOutput(update, info)
local from, cat
if otherTarget then
from = "an alternative title or related topic of '''" .. noredir(otherPage) .. "''', another redirect to the same title"
else
from = "an alternative title or related topic of '''[[:" .. otherPage.fullText .. "]]''', a former redirect to the same title"
end
cat = demo and "" or update and "Avoided double redirects to be updated" or "Avoided double redirects"
return frame:expandTemplate({
title = "Redirect template",
args = {
id = 'R avoided double redirect',
from = from,
info = update and "\n**" .. info or info,
["all category"] = cat,
name = "From an avoided double redirect"
}
})
end
if not noError then
if not thisTarget then
return formatError("This page is not a functioning redirect – possibly disabled by RfD.", demo)
elseif mw.title.equals(thisPage, thisTarget) then
return formatOutput(true, "<span class=\"error\">This is a broken redirect (it redirects to itself).</span>")
elseif not thisTarget.exists then
return formatOutput(true, "<span class=\"error\">This is a broken redirect (its target does not exist).</span>")
elseif not otherPage.exists then
return formatOutput(true, "<span class=\"error\">[[:" .. otherPage.fullText .. "]] does not exist.</span>")
elseif otherTarget and mw.title.equals(otherPage, otherTarget) then
return formatOutput(true, "<span class=\"error\">[[:" .. otherPage.fullText .. "]] is a broken redirect (it redirects to itself).</span>")
elseif otherTarget and not otherTarget.exists then
return formatOutput(true, "<span class=\"error\">[[:" .. otherPage.fullText .. "]] is a broken redirect (it redirects to a page that does not exist).</span>")
elseif mw.title.equals(thisTarget, otherPage) then
if not otherTarget then
return formatOutput(true, "<span class=\"error\">[[:" .. otherPage.fullText .. "]] is not a redirect, and this already points to it.</span> Most likely this template should be removed.")
elseif mw.title.equals(otherTarget, thisPage) then
return formatOutput(true, "<span class=\"error\">This is a circular redirect.</span> Please change the target of both this redirect and " .. noredir(otherPage) .. " to the correct article.")
end
return formatOutput(true, "<span class=\"error\">This page redirects to " .. noredir(otherPage) .. ", which redirects to [[:" .. otherTarget.fullText .. "]].</span> Please change this redirect's target to [[:" .. otherTarget.fullText .. "]] or otherwise resolve the situation.")
elseif not otherTarget then
return formatOutput(true, "<span class=\"error\">[[:" .. otherPage.fullText .. "]] is not a redirect.</span> Most likely this redirect should be updated to point to [[:" .. otherPage.fullText .. "]] now that it is no longer a redirect, and this template removed.\n** If that is not the correct target for this redirect, update or remove this template and/or the redirect itself and/or the other page as appropriate.")
elseif thisDoubleTarget then
if otherDoubleTarget then
if mw.title.equals(thisDoubleTarget, otherDoubleTarget) then
return formatOutput(true, "<span class=\"error\">Both this page and " .. noredir(otherPage) .. " are double redirects.</span> Please change the redirect target of both to "
.. (thisDoubleTarget.isRedirect and "the correct article." or "[[:" .. thisDoubleTarget.fullText .. "]] (or some other correct article)."))
end
return formatOutput(true, "<span class=\"error\">Both this page and " .. noredir(otherPage) .. " are double redirects.</span> Please fix them.")
end
return formatOutput(true, "<span class=\"error\">This is a double redirect.</span> Please fix it, possibly by changing it to [[:" .. otherTarget.fullText .. "]].")
elseif not mw.title.equals(thisTarget, otherTarget) then
return formatOutput(true, "<span class=\"error\">This page and " .. noredir(otherPage) .. " redirect to different articles.</span> Most likely you should change this redirect's target to [[:" .. otherTarget.fullText .. "]] to match.\n** If that is not the correct target for this redirect, update or remove this template and/or the redirect itself and/or the other page as appropriate.")
elseif thisTarget.fragment ~= otherTarget.fragment then
-- Should this case report for update?
return formatOutput(false, "Because [[Wikipedia:Double redirects|double redirects]] are disallowed,"
.. " both pages currently point to [[:" .. otherTarget.prefixedText .. "]] (but with different anchors).\n"
.. "**If " .. noredir(otherPage) .. " is retargeted or is expanded into a separate article, template, or other project page, "
.. " this redirect will be recategorized to be updated."
)
end
end
return formatOutput(false, "Because [[Wikipedia:Double redirects|double redirects]] are disallowed,"
.. " both pages currently point to [[:" .. otherTarget.fullText .. "]].\n"
.. "**If " .. noredir(otherPage) .. " is retargeted or is expanded into a separate article, template, or other project page, "
.. " this redirect will be recategorized to be updated."
)
end
return p
