Add Sniff for check autovivification on array

Author: anzin

Magento2/Sniffs/PHP/ArrayAutovivificationSniff.php

@@ -0,0 +1,66 @@
+<?php
+/**
+ * Copyright © Magento, Inc. All rights reserved.
+ * See COPYING.txt for license details.
+ */
+declare(strict_types=1);
+
+namespace Magento2\Sniffs\PHP;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Sniffs\Sniff;
+
+/**
+ * Sniff to validate array autovivification.
+ */
+class ArrayAutovivificationSniff implements Sniff
+{
+    /**
+     * String representation of error.
+     *
+     * @var string
+     */
+    private $warningMessage = 'Deprecated: Automatic conversion of false to array is deprecated.';
+
+    /**
+     * Warning violation code.
+     *
+     * @var string
+     */
+    private $warningCode = 'Autovivification';
+
+    /**
+     * @inheritdoc
+     */
+    public function register(): array
+    {
+        return [
+            T_VARIABLE
+        ];
+    }
+
+    /**
+     * @inheritdoc
+     */
+    public function process(File $phpcsFile, $stackPtr): void
+    {
+        $positionSquareBracket = $phpcsFile->findNext(T_OPEN_SQUARE_BRACKET, $stackPtr, $stackPtr + 2);
+
+        if ($positionSquareBracket) {
+            $tokens = $phpcsFile->getTokens();
+            $propertyTokenKey = array_keys(array_column($tokens, 'content'), $tokens[$stackPtr]['content']);
+
+            arsort($propertyTokenKey);
+
+            foreach ($propertyTokenKey as $tokenKey) {
+                if ($tokenKey < $stackPtr && $tokens[$tokenKey + 2]['content'] === '=') {
+                    if ($tokens[$tokenKey + 4]['content'] != 'false') {
+                        return;
+                    }
+
+                    $phpcsFile->addWarning($this->warningMessage, $positionSquareBracket, $this->warningCode);
+                }
+            }
+        }
+    }
+}