Initialize a translation function

It matches the API of ngettext().

tests/LanguagesTest.php

@@ -0,0 +1,41 @@
+<?php
+
+require_once 'application/Languages.php';
+
+/**
+ * Class LanguagesTest.
+ */
+class LanguagesTest extends PHPUnit_Framework_TestCase
+{
+    /**
+     * Test t() with a simple non identified value.
+     */
+    public function testTranslateSingleNotID()
+    {
+        $text = 'abcdé 564 fgK';
+        $this->assertEquals($text, t($text));
+    }
+
+    /**
+     * Test t() with a non identified plural form.
+     */
+    public function testTranslatePluralNotID()
+    {
+        $text = '%s sandwich';
+        $nText = '%s sandwiches';
+        $this->assertEquals('0 sandwich', t($text, $nText));
+        $this->assertEquals('1 sandwich', t($text, $nText, 1));
+        $this->assertEquals('2 sandwiches', t($text, $nText, 2));
+    }
+
+    /**
+     * Test t() with a non identified invalid plural form.
+     */
+    public function testTranslatePluralNotIDInvalid()
+    {
+        $text = 'sandwich';
+        $nText = 'sandwiches';
+        $this->assertEquals('sandwich', t($text, $nText, 1));
+        $this->assertEquals('sandwiches', t($text, $nText, 2));
+    }
+}