code review improvements

Author: karyna-t

dev/tests/static/testsuite/Magento/Test/Integrity/Di/CompilerTest.php

@@ -127,12 +127,9 @@ private function getPluginBlacklist(): array
             );
             $blacklistItems = [];
             foreach (glob($blacklistFiles) as $fileName) {
-                // phpcs:ignore Magento2.Performance.ForeachArrayMerge
-                $blacklistItems = array_merge(
-                    $blacklistItems,
-                    file($fileName, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES)
-                );
+                $blacklistItems[] = file($fileName, FILE_IGNORE_NEW_LINES | FILE_SKIP_EMPTY_LINES);
             }
+            $blacklistItems = array_merge([], ...$blacklistItems);
             $this->pluginBlacklist = $blacklistItems;
         }
         return $this->pluginBlacklist;
@@ -244,11 +241,10 @@ protected function _phpClassesDataProvider()
         $allowedFiles = array_keys($classes);
         foreach ($classes as $class) {
             if (!in_array($class, $output)) {
-                // phpcs:ignore Magento2.Performance.ForeachArrayMerge
-                $output = array_merge($output, $this->_buildInheritanceHierarchyTree($class, $allowedFiles));
-                $output = array_unique($output);
+                $output[] = $this->_buildInheritanceHierarchyTree($class, $allowedFiles);
             }
         }
+        $output = array_unique(array_merge([], ...$output));
 
         /** Convert data into data provider format */
         $outputClasses = [];

dev/tests/static/testsuite/Magento/Test/Integrity/Magento/Framework/Api/ExtensibleInterfacesTest.php

@@ -135,9 +135,10 @@ private function checkSetExtensionAttributes(
             } else {
                 // Get the parameter name via a regular expression capture because the class may
                 // not exist which causes a fatal error
-                preg_match('/\[\s\<\w+?>\s([?]?[\w]+)/s', $methodParameters[0]->__toString(), $matches);
+                preg_match('/\[\s\<\w+?>\s([?]?[\w\\\]+)/s', $methodParameters[0]->__toString(), $matches);
                 $isCorrectParameter = false;
-                if (isset($matches[1]) && '\\' . $matches[1] != $extensionInterfaceName) {
+                if (isset($matches[1])
+                    && ('\\' . ltrim($matches[1], '?')) === $extensionInterfaceName) {
                     $isCorrectParameter = true;
                 }