Difference between revisions of "Module:Navbar"

Revision as of 21:07, 31 March 2013

This Lua module is used on 11,200,000+ pages.
To avoid large-scale disruption and unnecessary server load, any changes to this module should first be tested in its /sandbox or /testcases subpages. The tested changes can then be added to this page in a single edit. Please consider discussing any changes on the talk page before implementing them.

This module is subject to page protection. It is a highly visible module in use by a very large number of pages, or is substituted very frequently. Because vandalism or mistakes would affect many pages, and even trivial editing might cause substantial load on the servers, it is protected from editing.

This is a Lua implementation of {{Navbar}}. It is used in Module:Navbox.

local p = {}

local HtmlBuilder = require('Module:HtmlBuilder')

function trim(s)
    return mw.ustring.match( s, "^%s*(.-)%s*$" )
end

function error(s)
    local span = HtmlBuilder.create('span')

    span
        .addClass('error')
        .css('float', 'left')
        .css('white-space', 'nowrap')
        .wikitext('Error: ' .. s)

    return tostring(span)
end

function getTitle( pageName )
    pageName = trim( pageName );
    if mw.ustring.sub(pageName, 1, 1) == ':' then
        return mw.title.new( mw.ustring.sub(pageName, 2) );
    else
        return mw.title.new( pageName, 'Template' );
    end    
end

function _navbar( args )
    if not args[1] then
        return error('No name provided')
    end
 
    local good, title;
    good, title = pcall( getTitle, args[1] );
    if not good then
        return error('Expensive parser function limit exceeded');
    end    

    if not title then
        return error('Page does not exist')
    end
 
    local mainpage = title.fullText;
    local talkpage = title.talkPageTitle and title.talkPageTitle.fullText or ''
    local editurl = title:fullUrl( 'action=edit' ); 
 
    local viewLink, talkLink, editLink = 'view', 'talk', 'edit'
    if args.mini then
        viewLink, talkLink, editLink = 'v', 't', 'e'
    end
 
    local div = HtmlBuilder.create( 'div' )
    div
        .addClass( 'noprint' )
        .addClass( 'plainlinks' )
        .addClass( 'hlist' )
        .addClass( 'navbar')
        .cssText( args.style )
 
    if args.mini then div.addClass('mini') end
 
    if not (args.mini or args.plain) then
        div
            .tag( 'span' )
                .css( 'word-spacing', 0 )
                .cssText( args.fontstyle )
                .wikitext( args.text or 'This box:' )
                .wikitext( ' ' )
    end
 
    if args.brackets then
        div
            .tag('span')
                .css('margin-right', '-0.125em')
                .cssText( args.fontstyle )
                .wikitext( '&#91;' )
                .newline();
    end
 
    local ul = div.tag('ul');
 
    ul
        .tag( 'li' )
            .addClass( 'nv-view' )
            .wikitext( '[[' .. mainpage .. '|' )
            .tag( 'span ' )
                .attr( 'title', 'View this template' )
                .cssText( args.fontstyle or '' )
                .wikitext( viewLink )
                .done()
            .wikitext( ']]' )
            .done()
        .tag( 'li' )
            .addClass( 'nv-talk' )
            .wikitext( '[[' .. talkpage .. '|' )
            .tag( 'span ' )
                .attr( 'title', 'Discuss this template' )
                .cssText( args.fontstyle or '' )
                .wikitext( talkLink )
                .done()
            .wikitext( ']]' );
 
    if not args.noedit then 
        ul
            .tag( 'li' )
                .addClass( 'nv-edit' )
                .wikitext( '[' .. editurl .. ' ' )
                .tag( 'span ' )
                    .attr( 'title', 'Edit this template' )
                    .cssText( args.fontstyle or '' )
                    .wikitext( editLink )
                    .done()
                .wikitext( ']' );
    end
 
    if args.brackets then
        div
            .tag('span')
                .css('margin-left', '-0.125em')
                .cssText( args.fontstyle or '' )
                .wikitext( '&#93;' )
                .newline();
    end
 
    return tostring(div)
end

function p.navbar(frame)
    local origArgs
    -- If called via #invoke, use the args passed into the invoking template.
    -- Otherwise, for testing purposes, assume args are being passed directly in.
    if frame == mw.getCurrentFrame() then
        origArgs = frame:getParent().args
    else
        origArgs = frame
    end
 
    -- ParserFunctions considers the empty string to be false, so to preserve the previous 
    -- behavior of {{navbar}}, change any empty arguments to nil, so Lua will consider
    -- them false too.
    args = {}
    for k, v in pairs(origArgs) do
        if v ~= '' then
            args[k] = v
        end
    end
 
    return _navbar(args)
end
 
return p