diff --git a/tests/Compiler/BaseTestCase.php b/tests/Compiler/BaseTestCase.php
index 7aec8dc..69cd3ca 100644
--- a/tests/Compiler/BaseTestCase.php
+++ b/tests/Compiler/BaseTestCase.php
@@ -20,10 +20,6 @@ abstract class BaseTestCase extends TestCase
         /* RENDERER */
     ];
 
-    /**
-     * @param Template $document
-     * @return string
-     */
     protected function compile(Template $document): string
     {
         $compiler = new Compiler();
@@ -34,10 +30,6 @@ protected function compile(Template $document): string
         return $compiler->compile($document)->getContent();
     }
 
-    /**
-     * @param string $string
-     * @return Template
-     */
     protected function parse(string $string): Template
     {
         $parser = new Parser();
diff --git a/tests/Directive/BaseTestCase.php b/tests/Directive/BaseTestCase.php
index 1349f14..2a8111c 100644
--- a/tests/Directive/BaseTestCase.php
+++ b/tests/Directive/BaseTestCase.php
@@ -28,10 +28,6 @@ abstract class BaseTestCase extends \Spiral\Tests\Stempler\Compiler\BaseTestCase
 
     protected const DIRECTIVES = [];
 
-    /**
- * @param Template $document
- * @return string
- */
     protected function compile(Template $document): string
     {
         $compiler = new Compiler();
diff --git a/tests/Directive/OnlyKnownTest.php b/tests/Directive/OnlyKnownTest.php
index 8011dde..0e2913f 100644
--- a/tests/Directive/OnlyKnownTest.php
+++ b/tests/Directive/OnlyKnownTest.php
@@ -30,10 +30,6 @@ public function testForeachEndForeach(): void
         );
     }
 
-    /**
-     * @param string $string
-     * @return Template
-     */
     protected function parse(string $string): Template
     {
         $parser = new Parser();
diff --git a/tests/Grammar/BaseTestCase.php b/tests/Grammar/BaseTestCase.php
index 31014bb..db130ae 100644
--- a/tests/Grammar/BaseTestCase.php
+++ b/tests/Grammar/BaseTestCase.php
@@ -12,10 +12,6 @@ abstract class BaseTestCase extends TestCase
 {
     protected const GRAMMARS = [];
 
-    /**
-     * @param array  $tokens
-     * @param string $source
-     */
     protected function assertTokens(array $tokens, string $source): void
     {
         $parsed = $this->tokens($source);
diff --git a/tests/Syntax/BaseTestCase.php b/tests/Syntax/BaseTestCase.php
index 68708a5..61d46cf 100644
--- a/tests/Syntax/BaseTestCase.php
+++ b/tests/Syntax/BaseTestCase.php
@@ -15,10 +15,6 @@ abstract class BaseTestCase extends TestCase
         /* GRAMMAR => SYNTAX */
     ];
 
-    /**
-     * @param string $string
-     * @return Template
-     */
     protected function parse(string $string): Template
     {
         $parser = new Parser();
diff --git a/tests/Transform/AttributesTest.php b/tests/Transform/AttributesTest.php
index 7c923c5..f1868d3 100644
--- a/tests/Transform/AttributesTest.php
+++ b/tests/Transform/AttributesTest.php
@@ -16,7 +16,7 @@ class AttributesTest extends BaseTestCase
 {
     public function testAggregatedAttribute(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<a href="" attr:aggregate></a>'
@@ -36,7 +36,7 @@ public function testAggregatedAttribute(): void
 
     public function testAggregatedAttributePattern(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<a href="${href}" attr:aggregate="prefix:a-"></a>'
@@ -57,7 +57,7 @@ public function testAggregatedAttributePattern(): void
 
     public function testAggregateInclude(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<a href="${href}" attr:aggregate="include:style"></a>'
@@ -78,7 +78,7 @@ public function testAggregateInclude(): void
 
     public function testAggregateExclude(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<a href="${href}" attr:aggregate="exclude:style"></a>'
@@ -99,7 +99,7 @@ public function testAggregateExclude(): void
 
     public function testAggregateSimple(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="element" as="element"/><element href="google.com" style="color:red"/>'
@@ -120,7 +120,7 @@ public function testAggregateSimple(): void
 
     public function testAggregateVoid(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="element" as="element"/><element href="google.com" blue/>'
@@ -140,7 +140,7 @@ public function testAggregateVoid(): void
 
     public function testAggregateBlock(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="element" as="element"/>'
@@ -161,7 +161,7 @@ public function testAggregateBlock(): void
 
     public function testAggregatePHP(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="element" as="element"/>'
@@ -182,7 +182,7 @@ public function testAggregatePHP(): void
 
     public function testAggregateVerbatim(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="element" as="element"/><element href="google.com" style="color: <?=\'red\'?>"/>'
@@ -202,7 +202,7 @@ public function testAggregateVerbatim(): void
 
     public function testEqualsToPHP(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="element" as="element"/><element href="google.com" class=<?=\'red\'?>/>'
diff --git a/tests/Transform/BaseTestCase.php b/tests/Transform/BaseTestCase.php
index 4fee482..381179c 100644
--- a/tests/Transform/BaseTestCase.php
+++ b/tests/Transform/BaseTestCase.php
@@ -39,7 +39,7 @@ protected function compile(string $source, array $visitors = [], LoaderInterface
 
     protected function parse(string $source, array $visitors = [], LoaderInterface $loader = null)
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', $source);
 
         $builder = $this->getBuilder($loader, $visitors);
@@ -78,9 +78,6 @@ protected function getVisitors(): array
         return [];
     }
 
-    /**
-     * @return LoaderInterface
-     */
     protected function getFixtureLoader(): LoaderInterface
     {
         return new DirectoryLoader(__DIR__ . '/../fixtures');
diff --git a/tests/Transform/ExtendsTest.php b/tests/Transform/ExtendsTest.php
index 97b2f7a..b790fec 100644
--- a/tests/Transform/ExtendsTest.php
+++ b/tests/Transform/ExtendsTest.php
@@ -18,7 +18,7 @@ class ExtendsTest extends BaseTestCase
 {
     public function testNoExtends(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<block:content>hello world</block:content>');
 
         $builder = $this->getBuilder($loader, []);
@@ -31,7 +31,7 @@ public function testNoExtends(): void
 
     public function testExtendsParent(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends:parent/><block:content>hello world</block:content>');
         $loader->set('parent', '<b><block:content>parent world</block:content></b>');
 
@@ -45,7 +45,7 @@ public function testExtendsParent(): void
 
     public function testExtendsParentBlock(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends:parent/><block:content>hello ${parent}</block:content>');
         $loader->set('parent', '<b><block:content>parent world</block:content></b>');
 
@@ -59,7 +59,7 @@ public function testExtendsParentBlock(): void
 
     public function testExtendsParentBlockWithNoAttribute(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends:parent/><block:content>hello ${parent}</block:content>');
         $loader->set('parent', '<b attr:aggregate><block:content>parent world</block:content></b>');
 
@@ -73,7 +73,7 @@ public function testExtendsParentBlockWithNoAttribute(): void
 
     public function testExtendsParentBlockWithAttribute(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends:parent class="red"/><block:content>hello ${parent}</block:content>');
         $loader->set('parent', '<b attr:aggregate><block:content>parent world</block:content></b>');
 
@@ -87,7 +87,7 @@ public function testExtendsParentBlockWithAttribute(): void
 
     public function testExtendsAttribute(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends:parent value="x"/><block:content>hello ${parent}</block:content>');
         $loader->set('parent', '<b value="${value}"><block:content>parent world</block:content></b>');
 
@@ -101,7 +101,7 @@ public function testExtendsAttribute(): void
 
     public function testExtendsViaPath(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends path="parent" value="x"/><block:content>hello ${parent}</block:content>');
         $loader->set('parent', '<b value="${value}"><block:content>parent world</block:content></b>');
 
@@ -115,7 +115,7 @@ public function testExtendsViaPath(): void
 
     public function testExtendsMultiple(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<extends:child/><block:data>root</block:data>');
         $loader->set('child', '<extends:parent/><block:content><i><block:data/></i></block:content>');
         $loader->set('parent', '<b><block:content/></b>');
@@ -130,7 +130,7 @@ public function testExtendsMultiple(): void
 
     public function testExtendsInline(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', 'hello <placeholder><extends:child/><block:data>root</block:data></placeholder>');
         $loader->set('child', '<extends:parent/><block:content><i><block:data/></i></block:content>');
         $loader->set('parent', '<b><block:content/></b>');
diff --git a/tests/Transform/ImportBundleTest.php b/tests/Transform/ImportBundleTest.php
index 1d34c0c..ee07600 100644
--- a/tests/Transform/ImportBundleTest.php
+++ b/tests/Transform/ImportBundleTest.php
@@ -18,7 +18,7 @@ class ImportBundleTest extends BaseTestCase
 {
     public function testNoImport(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<url href="google.com">hello world</url>');
         $loader->set('import', '<a href="${href}">${context}</a>');
 
@@ -32,7 +32,7 @@ public function testNoImport(): void
 
     public function testInlineBundle(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '
 <use:bundle path="bundle" ns="prefix"/>
 <prefix:url href="google.com">hello world</prefix:url>
@@ -56,7 +56,7 @@ public function testInlineBundle(): void
 
     public function testImportElementViaBundle(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '
 <use:bundle path="bundle" ns="prefix"/>
 <prefix:url href="google.com">hello world</prefix:url>
diff --git a/tests/Transform/ImportElementTest.php b/tests/Transform/ImportElementTest.php
index 7d22cb2..3b5b551 100644
--- a/tests/Transform/ImportElementTest.php
+++ b/tests/Transform/ImportElementTest.php
@@ -19,7 +19,7 @@ class ImportElementTest extends BaseTestCase
 {
     public function testNoImport(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<url href="google.com">hello world</url>');
         $loader->set('import', '<a href="${href}">${context}</a>');
 
@@ -33,7 +33,7 @@ public function testNoImport(): void
 
     public function testSimpleImport(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="google.com">hello world</url>'
@@ -50,7 +50,7 @@ public function testSimpleImport(): void
 
     public function testImportWithPHP(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="<?php echo \'google.com\'?>">hello world</url>'
@@ -67,7 +67,7 @@ public function testImportWithPHP(): void
 
     public function testImportWithOutput(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}">hello world</url>'
@@ -85,7 +85,7 @@ public function testImportWithOutput(): void
 
     public function testStringValueIntoPHP(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}">hello world</url>'
@@ -104,7 +104,7 @@ public function testStringValueIntoPHP(): void
 
     public function testOutputValueIntoPHPFromAttribute(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}" value="<?php echo \'bad\'?>">abc</url>'
@@ -123,7 +123,7 @@ public function testOutputValueIntoPHPFromAttribute(): void
 
     public function testOutputValueIntoPHPFromAttributeUsingOutput(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}" value="{{ \'OK\' }}">abc</url>'
@@ -142,7 +142,7 @@ public function testOutputValueIntoPHPFromAttributeUsingOutput(): void
 
     public function testValueIntoPHPFromMultiValue(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}" value="hello {{ \'OK\' }}">abc</url>'
@@ -161,7 +161,7 @@ public function testValueIntoPHPFromMultiValue(): void
 
     public function testValueIntoPHPFromMultiValueWithSpacing(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}" value="{{ \'OK\' }}  {{ \'cool\' }}">abc</url>'
@@ -181,7 +181,7 @@ public function testValueIntoPHPFromMultiValueWithSpacing(): void
 
     public function testValueIntoPHPFromMultiValueWithSpacingAround(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/>'
@@ -202,7 +202,7 @@ public function testValueIntoPHPFromMultiValueWithSpacingAround(): void
 
     public function testDefaultPHPValue(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}"></url>'
@@ -222,7 +222,7 @@ public function testDefaultPHPValue(): void
 
     public function testDefaultPHPValueArray(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/><url href="{{ $url }}"></url>'
@@ -242,7 +242,7 @@ public function testDefaultPHPValueArray(): void
 
     public function testHasInjectionEmpty(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="opt"/><opt>hello world</opt>'
@@ -263,7 +263,7 @@ public function testHasInjectionEmpty(): void
 
     public function testHasInjection(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="opt"/><opt><block:header>abc</block:header>hello world</opt>'
@@ -284,7 +284,7 @@ public function testHasInjection(): void
 
     public function testParentBlock(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="h"/><h><block:c>a<block:parent/></block:c></h>'
@@ -300,7 +300,7 @@ public function testParentBlock(): void
 
     public function testParentBlockShort(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="h"/><h c="a ${parent}"/>'
diff --git a/tests/Transform/ImportInlineTest.php b/tests/Transform/ImportInlineTest.php
index c82d127..5cc800a 100644
--- a/tests/Transform/ImportInlineTest.php
+++ b/tests/Transform/ImportInlineTest.php
@@ -18,7 +18,7 @@ class ImportInlineTest extends BaseTestCase
 {
     public function testNoImport(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '<url href="google.com">hello world</url>');
         $loader->set('import', '<a href="${href}">${context}</a>');
 
@@ -32,7 +32,7 @@ public function testNoImport(): void
 
     public function testInlineImport(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '
 <use:inline name="url">
     <a href="${href}">${context}</a>
@@ -50,7 +50,7 @@ public function testInlineImport(): void
 
     public function testInlineImportN(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set('root', '
 <use:inline name="url">
     <a href="${href}">${context}</a>
diff --git a/tests/Transform/ImportedStackTest.php b/tests/Transform/ImportedStackTest.php
index 80e1aa1..c0dc7e8 100644
--- a/tests/Transform/ImportedStackTest.php
+++ b/tests/Transform/ImportedStackTest.php
@@ -31,7 +31,7 @@ public function testEmptyStack(): void
 
     public function testImportedStack(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:element path="import" as="url"/>
@@ -54,7 +54,7 @@ public function testImportedStack(): void
 
     public function testStackDefinedInParent(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<extends:parent/>
@@ -89,7 +89,7 @@ public function testStackDefinedInParent(): void
 
     public function testStackDefinedInParentWithChild(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<extends:parent/>
@@ -126,7 +126,7 @@ public function testStackDefinedInParentWithChild(): void
 
     public function testGrid(): void
     {
-        $loader = $loader ?? new StringLoader();
+        $loader ??= new StringLoader();
         $loader->set(
             'root',
             '<use:dir dir="grid" ns="grid"/>