diff --git a/lib/internal/Magento/Framework/View/Asset/MergeStrategy/Direct.php b/lib/internal/Magento/Framework/View/Asset/MergeStrategy/Direct.php
index e6ff58efe071a..315c3ee204864 100644
--- a/lib/internal/Magento/Framework/View/Asset/MergeStrategy/Direct.php
+++ b/lib/internal/Magento/Framework/View/Asset/MergeStrategy/Direct.php
@@ -6,6 +6,8 @@
 namespace Magento\Framework\View\Asset\MergeStrategy;
 
 use Magento\Framework\App\Filesystem\DirectoryList;
+use Magento\Framework\App\ObjectManager;
+use Magento\Framework\Math\Random;
 use Magento\Framework\View\Asset;
 
 /**
@@ -31,27 +33,27 @@ class Direct implements \Magento\Framework\View\Asset\MergeStrategyInterface
     private $cssUrlResolver;
 
     /**
-     * @var \Magento\Framework\Math\Random
+     * @var Random
      */
     private $mathRandom;
 
     /**
      * @param \Magento\Framework\Filesystem $filesystem
      * @param \Magento\Framework\View\Url\CssResolver $cssUrlResolver
-     * @param \Magento\Framework\Math\Random|null $mathRandom
+     * @param Random|null $mathRandom
      */
     public function __construct(
         \Magento\Framework\Filesystem $filesystem,
         \Magento\Framework\View\Url\CssResolver $cssUrlResolver,
-        \Magento\Framework\Math\Random $mathRandom = null
+        Random $mathRandom = null
     ) {
         $this->filesystem = $filesystem;
         $this->cssUrlResolver = $cssUrlResolver;
-        $this->mathRandom = $mathRandom ?: \Magento\Framework\App\ObjectManager::getInstance()->get(\Magento\Framework\Math\Random::class);;
+        $this->mathRandom = $mathRandom ?: ObjectManager::getInstance()->get(Random::class);
     }
 
     /**
-     * {@inheritdoc}
+     * @inheritdoc
      */
     public function merge(array $assetsToMerge, Asset\LocalInterface $resultAsset)
     {
@@ -67,10 +69,9 @@ public function merge(array $assetsToMerge, Asset\LocalInterface $resultAsset)
     /**
      * Merge files together and modify content if needed
      *
-     * @param \Magento\Framework\View\Asset\MergeableInterface[] $assetsToMerge
-     * @param \Magento\ Framework\View\Asset\LocalInterface $resultAsset
-     * @return string
-     * @throws \Magento\Framework\Exception\LocalizedException
+     * @param array $assetsToMerge
+     * @param Asset\LocalInterface $resultAsset
+     * @return array|string
      */
     private function composeMergedContent(array $assetsToMerge, Asset\LocalInterface $resultAsset)
     {
diff --git a/lib/internal/Magento/Framework/View/Test/Unit/Asset/MergeStrategy/DirectTest.php b/lib/internal/Magento/Framework/View/Test/Unit/Asset/MergeStrategy/DirectTest.php
index 19b17b4b52596..c23f13745c79f 100644
--- a/lib/internal/Magento/Framework/View/Test/Unit/Asset/MergeStrategy/DirectTest.php
+++ b/lib/internal/Magento/Framework/View/Test/Unit/Asset/MergeStrategy/DirectTest.php
@@ -5,11 +5,13 @@
  */
 namespace Magento\Framework\View\Test\Unit\Asset\MergeStrategy;
 
-use Magento\Framework\Filesystem\Directory\WriteInterface;
-use \Magento\Framework\View\Asset\MergeStrategy\Direct;
-
 use Magento\Framework\App\Filesystem\DirectoryList;
+use Magento\Framework\Filesystem\Directory\WriteInterface;
+use Magento\Framework\View\Asset\MergeStrategy\Direct;
 
+/**
+ * Test for Magento\Framework\View\Asset\MergeStrategy\Direct.
+ */
 class DirectTest extends \PHPUnit\Framework\TestCase
 {
     /**
@@ -69,7 +71,8 @@ public function testMergeNoAssets()
             ->method('getUniqueHash')
             ->willReturn($uniqId);
         $this->tmpDir->expects($this->once())->method('writeFile')->with('foo/result' . $uniqId, '');
-        $this->tmpDir->expects($this->once())->method('renameFile')->with('foo/result' . $uniqId, 'foo/result', $this->staticDir);
+        $this->tmpDir->expects($this->once())->method('renameFile')
+            ->with('foo/result' . $uniqId, 'foo/result', $this->staticDir);
         $this->object->merge([], $this->resultAsset);
     }
 
@@ -83,7 +86,8 @@ public function testMergeGeneric()
             ->method('getUniqueHash')
             ->willReturn($uniqId);
         $this->tmpDir->expects($this->once())->method('writeFile')->with('foo/result' . $uniqId, 'onetwo');
-        $this->tmpDir->expects($this->once())->method('renameFile')->with('foo/result' . $uniqId, 'foo/result', $this->staticDir);
+        $this->tmpDir->expects($this->once())->method('renameFile')
+            ->with('foo/result' . $uniqId, 'foo/result', $this->staticDir);
         $this->object->merge($assets, $this->resultAsset);
     }
 
@@ -92,7 +96,7 @@ public function testMergeCss()
         $uniqId = '_f929c374767e00712449660ea673f2f5';
         $this->resultAsset->expects($this->exactly(3))
             ->method('getPath')
-            ->will($this->returnValue('foo/result'));
+            ->willReturn('foo/result');
         $this->resultAsset->expects($this->any())->method('getContentType')->will($this->returnValue('css'));
         $assets = $this->prepareAssetsToMerge(['one', 'two']);
         $this->cssUrlResolver->expects($this->exactly(2))
@@ -101,13 +105,14 @@ public function testMergeCss()
         $this->cssUrlResolver->expects($this->once())
             ->method('aggregateImportDirectives')
             ->with('12')
-            ->will($this->returnValue('1020'));
+            ->willReturn('1020');
         $this->mathRandomMock->expects($this->once())
             ->method('getUniqueHash')
             ->willReturn($uniqId);
         $this->staticDir->expects($this->never())->method('writeFile');
         $this->tmpDir->expects($this->once())->method('writeFile')->with('foo/result' . $uniqId, '1020');
-        $this->tmpDir->expects($this->once())->method('renameFile')->with('foo/result' . $uniqId, 'foo/result', $this->staticDir);
+        $this->tmpDir->expects($this->once())->method('renameFile')
+            ->with('foo/result' . $uniqId, 'foo/result', $this->staticDir);
         $this->object->merge($assets, $this->resultAsset);
     }