Adds is_rtl() function to Twig

lib/Twig/Functions.php

@@ -1,5 +1,7 @@
 <?php
+
 namespace MailPoet\Twig;
+
 use MailPoet\Config\ServicesChecker;
 
 if(!defined('ABSPATH')) exit;
@@ -86,6 +88,11 @@ class Functions extends \Twig_Extension {
         'do_action',
         'do_action',
         array('is_safe' => array('all'))
+      ),
+      new \Twig_SimpleFunction(
+        'is_rtl',
+        array($this, 'isRtl'),
+        array('is_safe' => array('all'))
       )
     );
   }
@@ -162,4 +169,8 @@ class Functions extends \Twig_Extension {
     $checker = new ServicesChecker();
     return $checker->isPremiumKeyValid(false);
   }
+
+  function isRtl() {
+    return is_rtl();
+  }
 }

tests/unit/Twig/FunctionsTest.php

@@ -0,0 +1,22 @@
+<?php
+
+namespace MailPoet\Test\Twig;
+
+use AspectMock\Test as Mock;
+use MailPoet\Twig\Functions;
+
+class FunctionsTest extends \MailPoetTest {
+  function testItExecutesIsRtlFunction() {
+    $template = array('template' => '{% if is_rtl() %}rtl{% endif %}');
+    $twig = new \Twig_Environment(new \Twig_Loader_Array($template));
+    $twig->addExtension(new Functions());
+
+    Mock::func('MailPoet\Twig', 'is_rtl', true);
+    $result = $twig->render('template');
+    expect($result)->equals('rtl');
+
+    Mock::func('MailPoet\Twig', 'is_rtl', false);
+    $result = $twig->render('template');
+    expect($result)->isEmpty();
+  }
+}

views/layout.html

@@ -35,7 +35,7 @@ jQuery('.toplevel_page_mailpoet-newsletters.menu-top-last')
 <%= do_action('mailpoet_styles_admin_after') %>
 
 <!-- rtl specific stylesheet -->
-<% if is_rtl %>
+<% if is_rtl() %>
   <%= stylesheet('rtl.css') %>
 <% endif %>