nggettext_extract failed to extract translatable string with printf format on html files

[fujiwarat]

Currently translate attribute works with grunt-angular-gettext but it's not useful for printf format.

E.g. I'd like to use gettext for the following text on html files:

<li>
{{user.status?'Disable':'Enable'}} user
</li>

to

<li>
{{sprintf(i18n._("%s user"), user.status?i18n._('Disable'):i18n._('Enable'))}}
</li>

I set ['_', 'N_'] to markerNames and attributes in Gruntfile.js file angular-gettext works but grunt nggettext_extract cannot extract "%s user", "Disable" and "Enable".

The following JavaScript file is used:

var gettext = require("angular-gettext");
var sprintf = require("sprintf-js").sprintf;

angular.module('test', ['gettext'])
    .run(function ($rootScope, $window, gettextCatalog) {
        gettextCatalog.setCurrentLanguage('ja');
        gettextCatalog.loadRemote('js/ja.json');
        gettextCatalog._ = gettextCatalog.getString;
        gettextCatalog.N_ = function(s) {
            return s;
        }
        $rootScope.i18n = gettextCatalog;
        $rootScope.sprintf = sprintf;
    });

If I could move those strings on html to JavaScript files, they would work with grunt nggettext_extract but there are a lot of translatable strings. sprintf() is used to get rid of non-translatable strings likes codes, html tags,