Module:Redirect: Difference between revisions

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    (handle apostrophes and other characters escaped by {{TALKPAGENAME}}, per protected edit request by User:Jackmcbarn)
    m (45 revisions imported from wikipedia:Module:Redirect: see Topic:Vtixlm0q28eo6jtf)
     
    (8 intermediate revisions by 5 users not shown)
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    -- Given a single page name determines what page it redirects to and returns the target page name, or the
    -- This module provides functions for getting the target of a redirect page.
    -- 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.


    -- Thus these are roughly the same:
    local p = {}
    -- [[{{#invoke:redirect|main|redirect-page-name}}]] and {{#invoke:redirect|main|redirect-page-name|bracket=yes}}
     
    -- 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)
    local target = 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*%[%[([^%[%]|]-)|[^%[%]]-%]%]"
    )
    return target and mw.uri.decode(target, 'PATH')
    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