Добавлена поддержка запоминания языка для аккаунта

Обновлена минимальная версия Yii2
Удалено немного хлама от Yii2 Advanced
Исправлены некоторые тесты

tests/codeception/common/unit/validators/LanguageValidatorTest.php

@@ -0,0 +1,53 @@
+<?php
+namespace codeception\common\unit\validators;
+
+use Codeception\Specify;
+use common\validators\LanguageValidator;
+use ReflectionClass;
+use tests\codeception\common\unit\TestCase;
+
+class LanguageValidatorTest extends TestCase {
+    use Specify;
+
+    public function testGetFilesNames() {
+        $this->specify('get list of 2 languages: ru and en', function() {
+            $model = $this->createModelWithFixturePath();
+            expect($this->callProtected($model, 'getFilesNames'))->equals(['en', 'ru']);
+        });
+    }
+
+    public function testValidateValue() {
+        $this->specify('get null, because language is supported', function() {
+            $model = $this->createModelWithFixturePath();
+            expect($this->callProtected($model, 'validateValue', 'ru'))->null();
+        });
+
+        $this->specify('get error message, because language is unsupported', function() {
+            $model = $this->createModelWithFixturePath();
+            expect($this->callProtected($model, 'validateValue', 'by'))->equals([
+                $model->message,
+                [],
+            ]);
+        });
+    }
+
+    /**
+     * @return LanguageValidator
+     */
+    private function createModelWithFixturePath() {
+        return new class extends LanguageValidator {
+            public function getFolderPath() {
+                return __DIR__ . '/../fixtures/data/i18n';
+            }
+        };
+    }
+
+    private function callProtected($object, string $function, ...$args) {
+        $class = new ReflectionClass($object);
+        $method = $class->getMethod($function);
+        $method->setAccessible(true);
+
+        return $method->invokeArgs($object, $args);
+    }
+
+}