Issue #2546618 followup by plach: Document that we don't depend on the Symfony...

Issue #2546618 followup by plach: Document that we don't depend on the Symfony Translation component.

core/vendor/symfony/translation/Tests/DataCollectorTranslatorTest.php

+<?php
+
+/*
+ * This file is part of the Symfony package.
+ *
+ * (c) Fabien Potencier <fabien@symfony.com>
+ *
+ * For the full copyright and license information, please view the LICENSE
+ * file that was distributed with this source code.
+ */
+
+namespace Symfony\Component\Translation\Tests;
+
+use Symfony\Component\Translation\Translator;
+use Symfony\Component\Translation\DataCollectorTranslator;
+use Symfony\Component\Translation\Loader\ArrayLoader;
+
+class DataCollectorTranslatorTest extends \PHPUnit_Framework_TestCase
+{
+    protected function setUp()
+    {
+        if (!class_exists('Symfony\Component\HttpKernel\DataCollector\DataCollector')) {
+            $this->markTestSkipped('The "DataCollector" is not available');
+        }
+    }
+    public function testCollectMessages()
+    {
+        $collector = $this->createCollector();
+        $collector->setFallbackLocales(array('fr', 'ru'));
+
+        $collector->trans('foo');
+        $collector->trans('bar');
+        $collector->transChoice('choice', 0);
+        $collector->trans('bar_ru');
+
+        $expectedMessages = array();
+        $expectedMessages[] = array(
+              'id' => 'foo',
+              'translation' => 'foo (en)',
+              'locale' => 'en',
+              'domain' => 'messages',
+              'state' => DataCollectorTranslator::MESSAGE_DEFINED,
+        );
+        $expectedMessages[] = array(
+              'id' => 'bar',
+              'translation' => 'bar (fr)',
+              'locale' => 'fr',
+              'domain' => 'messages',
+              'state' => DataCollectorTranslator::MESSAGE_EQUALS_FALLBACK,
+        );
+        $expectedMessages[] = array(
+              'id' => 'choice',
+              'translation' => 'choice',
+              'locale' => 'en',
+              'domain' => 'messages',
+              'state' => DataCollectorTranslator::MESSAGE_MISSING,
+        );
+        $expectedMessages[] = array(
+              'id' => 'bar_ru',
+              'translation' => 'bar (ru)',
+              'locale' => 'ru',
+              'domain' => 'messages',
+              'state' => DataCollectorTranslator::MESSAGE_EQUALS_FALLBACK,
+        );
+
+        $this->assertEquals($expectedMessages, $collector->getCollectedMessages());
+    }
+
+    private function createCollector()
+    {
+        $translator = new Translator('en');
+        $translator->addLoader('array', new ArrayLoader());
+        $translator->addResource('array', array('foo' => 'foo (en)'), 'en');
+        $translator->addResource('array', array('bar' => 'bar (fr)'), 'fr');
+        $translator->addResource('array', array('bar_ru' => 'bar (ru)'), 'ru');
+
+        $collector = new DataCollectorTranslator($translator);
+
+        return $collector;
+    }
+}