Module:Template translation/sandbox

This is the module sandbox page for Module:Template translation (diff).

Module documentation

This Lua module is used on approximately 114,000 pages.
To avoid major disruption and server load, any changes should be tested in the module's /sandbox or /testcases subpages, or in your own module sandbox. The tested changes can be added to this page in a single edit. Consider discussing changes on the talk page before implementing them.

Purpose

This template, originally named "Translatable template" (often abbreviated as TNT, but which never meant "dynamite"!) is used to show translatable templates in the language of the current page. Templates, like all other MediaWiki pages, can be translated using the Translate extension, which creates subpages with the form "pagename/language code". The template first checks if the name of the page contains a language code. If it does, it then checks if the template name given as a first parameter has a translation in that language. If the page name does not contain a language code, or if the navigation template doesn't exist in that language, it will display the English template.

How to use

{{Translatable template|name of template|parameters....}}
{{TNT|name of template|parameters....}}
{{tnt|name of template|parameters....}}

The above simplied syntax cannot work if the named template also needs to be transcluded in other translatable templates, because it would cause self-recursion of {{Translatable template}}. An alternative is to use {{Translatable template name}} which does not expand the template with its parameters, but only returns the resolved template name, which can then be transcluded normally:

{{{{Translatable template name|name of template}}|parameters....}}
{{{{TNTN|name of template}}|parameters....}}
{{{{tntn|name of template}}|parameters....}}

Example (from Meta:Administrator):

{{Translatable template|User groups}} or {{TNT|User groups}}

which includes translated versions of {{User groups}} if it exists, or the English version if translations don't exist.

Parameters

The current version of the template may now include any kind of named or numbered parameters, whose values will be transferred into the called template (with the exception of parameter 1 containing the basename of the translatable template to transclude). Numbered parameters will be shifted down by one position, all named parameters will be passed unchanged.

One named parameter is treated specially:

{{Translatable template|namespace=:somename:|page name|parameters....}}
{{TNT|namespace=:somename:|page name|parameters....}}
{{tnt|namespace=:somename:|page name|parameters....}}

This namespace will be used to specify another namespace from which the translatable pagename will be transcluded, instead of referencing the page name from the default :Template: namespace. Note that this parameter is also passed (without modification) within the parameters of the transclusion.

Example with one parameters (from Global sysops):

{{TNT|Special global permissions/Seealso|Global sysops}}

where the second parameter "Global sysops" is the value of the first numbered parameter transferred into called page "Special global permissions/Seealso".

Dependency

Module:Template translation (standard version)
Module:Template translation/sandbox (used when this template is called with optional dummy parameter sandbox=/sandbox, for testing only)

local this = {}

function this.checkLanguage(subpage)
    --[[Check first if there's an any invalid character that would cause the
        mw.language.isKnownLanguageTag function() to throw an exception:
        - all ASCII controls in [\000-\031\127],
        - double quote ("), sharp sign (#), ampersand (&), apostrophe ('),
        - slash (/), colon (:), semicolon (;), lower than (<), greater than (>),
        - brackets and braces ([, ], {, }), pipe (|), backslash (\\)
        All other characters are accepted, including space and all non-ASCII
        characters (including \192, which is invalid in UTF-8).
    --]]
    if mw.language.isValidCode(subpage) and mw.language.isKnownLanguageTag(subpage)
    --[[However "SupportedLanguages" are too restrictive, as they discard many
        valid BCP47 script variants (only because MediaWiki still does not
        define automatic transliterators for them, e.g. "en-dsrt" or
        "fr-brai" for French transliteration in Braille), and country variants,
        (useful in localized data, even if they are no longer used for
        translations, such as zh-cn, also useful for legacy codes).
        We want to avoid matching subpagenames containing any uppercase letter,
        (even if they are considered valid in BCP 47, in which they are
        case-insensitive; they are not "SupportedLanguages" for MediaWiki, so
        they are not "KnownLanguageTags" for MediaWiki).
        To be more restrictive, we exclude any character that is not
        ASCII and not a lowercase letter, minus-hyphen, or digit, and any code
        that does not start by a letter or does not finish by a letter or digit.
        of that has more than 8 characters between hyphens, or has two hyphens.
    --]]
    or  string.find(subpage, "^[%l][%-%d%l]*[%d%l]$") ~= nil
    and string.find(subpage, "[%d%l][%d%l][%d%l][%d%l][%d%l][%d%l][%d%l][%d%l][%d%l]") == nil
    and string.find(subpage, "%-%-") == nil
    then
        return subpage
    end
    -- Otherwise there's currently no known language subpage
    return default
end

--[[Get the language of the given page, if it is a translation.
--]]
function this.getTitleLanguage(title, default)
    --[[This code does not work in all namespaces where the Translate tool works:
    local subpage = title.subpageText
    ]]
    local titleparts = mw.text.split(title.fullText, '/')
    local subpage = titleparts[#titleparts]
    return this.checkLanguage(subpage, default)
end

--[[Get the language of the current page, if it is a translation.
--]]
function this.getCurrentLanguage(default)
    return this.getTitleLanguage(mw.title.getCurrentTitle(), default)
end

--[[Get the language of the current frame, if it is a translation.
--]]
function this.getFrameLanguage(frame)
    local args = frame.args
    local default = args['default'] or ''
    return this.getTitleLanguage(frame:getParent():getTitle(), default)
end

--[[If on a translation subpage (like Foobar/de), this function renders
    a given template in the same language, if the translation is available.
    Otherwise, the template is rendered in its default language, without
    modification.
    This is aimed at replacing the current implementation of Template:TNT.
    ]]
function this.renderTranslatedTemplate(frame)
    local args = frame.args
    local pagename = args['template']
    
    --[[Check whether the pagename is actually in the Template namespace, or
        if we're transcluding a main-namespace page.
        (added for backward compatibility of Template:TNT)
        ]]
    local title
    local namespace = args['namespace'] or ''
    if namespace ~= '' -- Checks for namespace parameter for custom ns.
    then
        title = mw.title.new(pagename, namespace) or {} -- Costly
    else -- Supposes that set page is in ns10.
    	namespace = 'Template'
        title = mw.title.new(pagename, namespace) or {} -- Costly
        if (title.id or 0) == 0
        then -- not found in the Template namespace, assume the main namespace (for backward compatibility)
    	    namespace = ''
            title = mw.title.new(pagename, namespace) or {} -- Costly
        end
    end
    
    -- Get the last subpage and check if it matches a known language code.
    local subpage = args['uselang'] or ''
    if subpage == ''
    then
        subpage = this.getFrameLanguage(frame)
    end
    if subpage == ''
    then
        -- Check if a translation of the pagename exists in English
        local newtitle = mw.title.new(pagename .. '/' .. 'en', namespace) or {} -- Costly
        -- Use the translation when it exists
        if (newtitle.id or 0) ~= 0
        then
            title = newtitle
        end
    else
        -- Check if a translation of the pagename exists in that language
        local newtitle = mw.title.new(pagename .. '/' .. subpage, namespace) or {} -- Costly
        if (newtitle.id or 0) == 0
        then
            -- Check if a translation of the pagename exists in English
            newtitle = mw.title.new(pagename .. '/' .. 'en', namespace) or {} -- Costly
        end
        -- Use the translation when it exists
        if (newtitle.id or 0) ~= 0
        then
            title = newtitle
        end
    end
    
    -- At this point the title should exist, otherwise render a red link to the missing page (resolved in its assumed namespace)
    if (title.id or 0) == 0
    then
    	return '[[' .. title.prefixedText .. ']]'
    end
    
    -- Copy args pseudo-table to a proper table so we can feed it to expandTemplate.
    -- Then render the pagename.
    local arguments = {}
    for k, v in pairs((frame:getParent() or {}).args) do
        -- numbered args >= 1 need to be shifted
    	local n = tonumber(k) or 0
    	if n > 0
    	then
    		if n >= 2
    		then
                arguments[n - 1] = v
            end
        else
            arguments[k] = v
        end
    end
    arguments['template'] = title.prefixedText -- override the existing parameter of the base template name supplied with the full name of the actual template expanded
    arguments['namespace'] = nil -- discard the specified namespace override
    
    return frame:expandTemplate{title = ':' .. title.prefixedText, args = arguments}
end

return this

Purpose

How to use

Parameters

Dependency

See also