diff --git a/src/Extension/CoreExtension.php b/src/Extension/CoreExtension.php
index bc837fcb2..866d99035 100644
--- a/src/Extension/CoreExtension.php
+++ b/src/Extension/CoreExtension.php
@@ -348,7 +348,7 @@ namespace {
     use Twig\Source;
     use Twig\Template;
 
-/**
+    /**
  * Cycles over a value.
  *
  * @param \ArrayAccess|array $values
diff --git a/src/Extension/HtmlExtension.php b/src/Extension/HtmlExtension.php
index 1aa1f8c4c..7e83083eb 100644
--- a/src/Extension/HtmlExtension.php
+++ b/src/Extension/HtmlExtension.php
@@ -54,14 +54,14 @@ final class HtmlExtension extends AbstractExtension
                 if (!class_exists(MimeTypes::class)) {
                     throw new \LogicException('The "data_uri" function requires the symfony/mime package to be installed.');
                 }
-    
+
                 $this->mimeTypes = new MimeTypes();
             }
 
             try {
                 $tmp = tempnam(sys_get_temp_dir(), 'mime');
                 file_put_contents($tmp, $data);
-                
+
                 if (null === $mime = $this->mimeTypes->guessMimeType($tmp)) {
                     $mime = 'text/plain';
                 }
@@ -93,12 +93,12 @@ function twig_html_classes(...$args): string
 {
     $classes = [];
     foreach ($args as $i => $arg) {
-        if (is_string($arg)) {
+        if (\is_string($arg)) {
             $classes[] = $arg;
-        } elseif (is_array($arg)) {
+        } elseif (\is_array($arg)) {
             foreach ($arg as $class => $condition) {
-                if (!is_string($class)) {
-                    throw new RuntimeError(sprintf('The html_classes function argument %d (key %d) should be a string, got "%s".', $i, $class, gettype($class)));
+                if (!\is_string($class)) {
+                    throw new RuntimeError(sprintf('The html_classes function argument %d (key %d) should be a string, got "%s".', $i, $class, \gettype($class)));
                 }
                 if (!$condition) {
                     continue;
@@ -106,7 +106,7 @@ function twig_html_classes(...$args): string
                 $classes[] = $class;
             }
         } else {
-            throw new RuntimeError(sprintf('The html_classes function argument %d should be either a string or an array, got "%s".', $i, gettype($arg)));
+            throw new RuntimeError(sprintf('The html_classes function argument %d should be either a string or an array, got "%s".', $i, \gettype($arg)));
         }
     }
 
diff --git a/tests/ParserTest.php b/tests/ParserTest.php
index 16a0efb12..8920f9fca 100644
--- a/tests/ParserTest.php
+++ b/tests/ParserTest.php
@@ -14,7 +14,6 @@ namespace Twig\Tests;
 use PHPUnit\Framework\TestCase;
 use Twig\Environment;
 use Twig\Loader\LoaderInterface;
-use Twig\Node\MacroNode;
 use Twig\Node\Node;
 use Twig\Node\SetNode;
 use Twig\Node\TextNode;
diff --git a/tests/Profiler/Dumper/AbstractTest.php b/tests/Profiler/Dumper/AbstractTest.php
index 3a11433cd..daaf83cd1 100644
--- a/tests/Profiler/Dumper/AbstractTest.php
+++ b/tests/Profiler/Dumper/AbstractTest.php
@@ -11,9 +11,8 @@ namespace Twig\Tests\Profiler\Dumper;
  * file that was distributed with this source code.
  */
 
-use Twig\Profiler\Profile;
-
 use PHPUnit\Framework\TestCase;
+use Twig\Profiler\Profile;
 
 abstract class AbstractTest extends TestCase
 {