Added Files/Create sniff to create required files if these do not exist

Author: michalbundyra

src/ZendCodingStandard/Sniffs/Files/CreateSniff.php

@@ -0,0 +1,85 @@
+<?php
+/**
+ * @see       https://github.com/zendframework/zend-coding-standard for the canonical source repository
+ * @copyright https://github.com/zendframework/zend-coding-standard/blob/master/COPYRIGHT.md Copyright
+ * @license   https://github.com/zendframework/zend-coding-standard/blob/master/LICENSE.md New BSD License
+ */
+
+declare(strict_types=1);
+
+namespace ZendCodingStandard\Sniffs\Files;
+
+use PHP_CodeSniffer\Files\File;
+use PHP_CodeSniffer\Sniffs\Sniff;
+
+use function file_exists;
+use function touch;
+
+use const T_INLINE_HTML;
+use const T_MD_LINE;
+use const T_OPEN_TAG;
+
+/**
+ * This sniff should run only once to create all missing files.
+ * It's hacky solution, because sniffs works only on existing
+ * files. So here we try to run the sniff on any file to check
+ * for required files, and on fixing we create them.
+ */
+class CreateSniff implements Sniff
+{
+    /**
+     * @var string[]
+     */
+    public $supportedTokenizers = [
+        'MD',
+        'PHP',
+    ];
+
+    public $files = [
+        'COPYRIGHT.md',
+        'LICENSE.md',
+    ];
+
+    /**
+     * @var bool
+     */
+    private $run = false;
+
+    /**
+     * @return int[]
+     */
+    public function register() : array
+    {
+        return [
+            T_INLINE_HTML,
+            T_MD_LINE,
+            T_OPEN_TAG,
+        ];
+    }
+
+    /**
+     * @param int $stackPtr
+     * @return int
+     */
+    public function process(File $phpcsFile, $stackPtr)
+    {
+        if ($this->run) {
+            return $phpcsFile->numTokens + 1;
+        }
+        $this->run = true;
+
+        foreach ($this->files as $file) {
+            if (! file_exists($file)) {
+                $error = 'File %s does not exist';
+                $data = [$file];
+                $fix = $phpcsFile->addFixableError($error, 0, 'NotExists', $data);
+
+                if ($fix) {
+                    touch($file);
+                }
+            }
+        }
+
+        return $phpcsFile->numTokens + 1;
+    }
+}