diff --git a/extensions/bootstrap/Progress.php b/extensions/bootstrap/Progress.php
index ed2d37d..184451c 100644
--- a/extensions/bootstrap/Progress.php
+++ b/extensions/bootstrap/Progress.php
@@ -48,7 +48,7 @@ use yii\helpers\Html;
  *     'bars' => [
  *         ['percent' => 30, 'options' => ['class' => 'bar-danger']],
  *         ['percent' => 30, 'label' => 'test', 'options' => ['class' => 'bar-success']],
- *         ['percent' => 35, 'options' => array['class' => 'bar-warning']],
+ *         ['percent' => 35, 'options' => ['class' => 'bar-warning']],
  *     ]
  * ]);
  * ```
diff --git a/extensions/swiftmailer/Mailer.php b/extensions/swiftmailer/Mailer.php
index 3418d8d..fda0477 100644
--- a/extensions/swiftmailer/Mailer.php
+++ b/extensions/swiftmailer/Mailer.php
@@ -17,9 +17,9 @@ use yii\mail\BaseMailer;
  * To use Mailer, you should configure it in the application configuration like the following,
  *
  * ~~~
- * 'components' => array(
+ * 'components' => [
  *     ...
- *     'email' => array(
+ *     'email' => [
  *         'class' => 'yii\swiftmailer\Mailer',
  *         'transport' => [
  *             'class' => 'Swift_SmtpTransport',
@@ -29,9 +29,9 @@ use yii\mail\BaseMailer;
  *             'port' => '587',
  *             'encryption' => 'tls',
  *         ],
- *     ),
+ *     ],
  *     ...
- * ),
+ * ],
  * ~~~
  *
  * You may also skip the configuration of the [[transport]] property. In that case, the default
diff --git a/framework/yii/web/AssetConverter.php b/framework/yii/web/AssetConverter.php
index a93b915..1b7d1c8 100644
--- a/framework/yii/web/AssetConverter.php
+++ b/framework/yii/web/AssetConverter.php
@@ -74,11 +74,11 @@ class AssetConverter extends Component implements AssetConverterInterface
 			'{from}' => escapeshellarg("$basePath/$asset"),
 			'{to}' => escapeshellarg("$basePath/$result"),
 		]);
-		$descriptor = array(
-			1 => array('pipe', 'w'),
-			2 => array('pipe', 'w'),
-		);
-		$pipes = array();
+		$descriptor = [
+			1 => ['pipe', 'w'],
+			2 => ['pipe', 'w'],
+		];
+		$pipes = [];
 		$proc = proc_open($command, $descriptor, $pipes, $basePath);
 		$stdout = stream_get_contents($pipes[1]);
 		$stderr = stream_get_contents($pipes[2]);
diff --git a/tests/unit/framework/mail/BaseMessageTest.php b/tests/unit/framework/mail/BaseMessageTest.php
index d80d4f7..35fa549 100644
--- a/tests/unit/framework/mail/BaseMessageTest.php
+++ b/tests/unit/framework/mail/BaseMessageTest.php
@@ -69,7 +69,7 @@ class BaseMessageTest extends TestCase
 class TestMailer extends BaseMailer
 {
 	public $messageClass = 'yiiunit\framework\mail\TestMessage';
-	public $sentMessages = array();
+	public $sentMessages = [];
 
 	protected function sendMessage($message)
 	{