Module:Redirect
Jump to navigation
Jump to search
The printable version is no longer supported and may have rendering errors. Please update your browser bookmarks and please use the default browser print function instead.
Documentation for this module may be created at Module:Redirect/doc
-- This module provides functions for getting the target of a redirect page.
local p = {}
-- Gets a mw.title object, using pcall to avoid generating script errors if we
-- are over the expensive function count limit (among other possible causes).
local function getTitle(...)
local success, titleObj = pcall(mw.title.new, ...)
if success then
return titleObj
else
return nil
end
end
-- Gets the name of a page that a redirect leads to, or nil if it isn't a
-- redirect.
function p.getTargetFromText(text)
return string.match(
text,
"^%s*#[Rr][Ee][Dd][Ii][Rr][Ee][Cc][Tt]%s*:?%s*%[%[([^%[%]|]-)%]%]"
) or string.match(
text,
"^%s*#[Rr][Ee][Dd][Ii][Rr][Ee][Cc][Tt]%s*:?%s*%[%[([^%[%]|]-)|[^%[%]]-%]%]"
)
end
-- Gets the target of a redirect. If the page specified is not a redirect,
-- returns nil.
function p.getTarget(page, fulltext)
-- Get the title object. Both page names and title objects are allowed
-- as input.
local titleObj
if type(page) == 'string' or type(page) == 'number' then
titleObj = getTitle(page)
elseif type(page) == 'table' and type(page.getContent) == 'function' then
titleObj = page
else
error(string.format(
"bad argument #1 to 'getTarget'"
.. " (string, number, or title object expected, got %s)",
type(page)
), 2)
end
if not titleObj or not titleObj.isRedirect then
return nil
end
-- Find the target by using string matching on the page content.
local target = p.getTargetFromText(titleObj:getContent() or "")
if target then
local targetTitle = getTitle(target)
if targetTitle then
if fulltext then
return targetTitle.fullText
else
return targetTitle.prefixedText
end
else
return nil
end
else
-- The page is a redirect, but matching failed. This indicates a bug in
-- the redirect matching pattern, so throw an error.
error(string.format(
'could not parse redirect on page "%s"',
fulltext and titleObj.fullText or titleObj.prefixedText
))
end
end
--[[
-- Given a single page name determines what page it redirects to and returns the
-- target page name, or the passed page name when not a redirect. The passed
-- page name can be given as plain text or as a page link.
--
-- Returns page name as plain text, or when the bracket parameter is given, as a
-- page link. Returns an error message when page does not exist or the redirect
-- target cannot be determined for some reason.
--]]
function p.luaMain(rname, bracket, fulltext)
if type(rname) ~= "string" or not rname:find("%S") then
return nil
end
bracket = bracket and "[[%s]]" or "%s"
rname = rname:match("%[%[(.+)%]%]") or rname
local target = p.getTarget(rname, fulltext)
local ret = target or rname
ret = getTitle(ret)
if ret then
if fulltext then
ret = ret.fullText
else
ret = ret.prefixedText
end
return bracket:format(ret)
else
return nil
end
end
-- Provides access to the luaMain function from wikitext.
function p.main(frame)
local args = require('Module:Arguments').getArgs(frame, {frameOnly = true})
return p.luaMain(args[1], args.bracket, args.fulltext) or ''
end
-- Returns true if the specified page is a redirect, and false otherwise.
function p.luaIsRedirect(page)
local titleObj = getTitle(page)
if not titleObj then
return false
end
if titleObj.isRedirect then
return true
else
return false
end
end
-- Provides access to the luaIsRedirect function from wikitext, returning 'yes'
-- if the specified page is a redirect, and the blank string otherwise.
function p.isRedirect(frame)
local args = require('Module:Arguments').getArgs(frame, {frameOnly = true})
if p.luaIsRedirect(args[1]) then
return 'yes'
else
return ''
end
end
return p