This allows template users to use their own twig extensions if they want, while also allowing us to remove the "twigInit" hook. Hooks come at a price, and it doesn't make much sense to use them in this case, as they would only be useful if a module wants to add a twig extension even if the code instantiating SimpleSAML_XHTML_Template does not belong to that module. This could lead to unexpected behaviour (i.e. a module adding a hook that creates trouble for the templates defined in another module), so given the lack of use cases supporting the hook and the possible negative consequences implied, it's better to remove it.

This way we we allow those writing themes to use twig extensions, filters, or anything they may need.

This allows custom themes to inject data for all templates by simply adding a new hook.

Make the language parameter name available to the templates, and remove that parameter from the queryParams entry in the template data.

This allows us to focus on the “real” parameters, ignoring language selection routines. It also allows us to build our own language bar the way we want it, not only with links.

This allows us to build the language switching links even when we have query parameters that would otherwise get lost.

Add a couple of methods to perform translations with PHP's native gettext implementation, and start using them.

Since the class names were prepended with "\", the original extension was used, instead of our own wrapper. This fixes that issue, and sets the two new methods in SimpleSAML\Locale\Translate as the functions to use to replace the calls to gettext() and ngettext(). Support for the old translation system is still missing for twig templates.

Define SimpleSAML\XHTML\Template::$twig as a property (previously only set in the constructor) and make sure we use proper type checking when using it.

This makes instanciating the Translate/Template-class unnecessary.

Both have been migrated to use namespaces.

Move the list of language localized names to the SimpleSAML\Locale\Language class, and make the array of languages generated by SimpleSAML_XHTML_Template::generateLanguageBar() a bit more useful.

Now works for:
new SimpleSAML_XHTML_Template($globalConfig, 'saml:sp/wrong_authncontextclassref.tpl.php');

That is, the following styles work:
* SimpleSAML_XHTML_Template($config, 'hostnames.php');
* SimpleSAML_XHTML_Template($globalConfig, 'negotiate:disable.php');

These do not:

* SimpleSAML_XHTML_Template($this->config, 'discopower:disco-tpl.php', 'disco');
* SimpleSAML_XHTML_Template($globalConfig, 'saml:sp/wrong_authncontextclassref.tpl.php');
* new SimpleSAML_XHTML_Template($config, 'metadata.php', 'admin');
* SimpleSAML_XHTML_Template($config, 'consentAdmin:consentadmin.php', 'consentAdmin:consentadmin');

Loading from themes also not in place

Restore the rest of the public methods in SimpleSAML_XHTML_Template that were removed, make them wrappers of the new methods, and mark them as deprecated.