Config: can use custom LocalFile object

src/Config.php

@@ -52,6 +52,7 @@
  * @property string     $generator       The documentation generator to use.
  * @property string     $filter          The filter to use for the run.
  * @property string[]   $bootstrap       One of more files to include before the run begins.
+ * @property string     $localFile       The LocalFile object to use in FileList.
  * @property int|string $reportWidth     The maximum number of columns that reports should use for output.
  *                                       Set to "auto" for have this value changed to the width of the terminal.
  * @property int        $errorSeverity   The minimum severity an error must have to be displayed.
@@ -138,6 +139,7 @@ class Config
         'generator'       => null,
         'filter'          => null,
         'bootstrap'       => null,
+        'localFile'       => null,
         'reports'         => null,
         'basepath'        => null,
         'reportWidth'     => null,
@@ -540,6 +542,7 @@ public function restoreDefaults()
         $this->generator       = null;
         $this->filter          = null;
         $this->bootstrap       = [];
+        $this->localFile       = null;
         $this->basepath        = null;
         $this->reports         = ['full' => null];
         $this->reportWidth     = 'auto';

src/Files/FileList.php

@@ -17,6 +17,7 @@
 use PHP_CodeSniffer\Autoload;
 use PHP_CodeSniffer\Config;
 use PHP_CodeSniffer\Exceptions\DeepExitException;
+use PHP_CodeSniffer\Exceptions\RuntimeException;
 use PHP_CodeSniffer\Ruleset;
 use PHP_CodeSniffer\Util\Common;
 use RecursiveArrayIterator;
@@ -194,7 +195,16 @@ public function current()
     {
         $path = key($this->files);
         if (isset($this->files[$path]) === false) {
-            $this->files[$path] = new LocalFile($path, $this->ruleset, $this->config);
+            if ($this->config->localFile === null) {
+                $this->files[$path] = new LocalFile($path, $this->ruleset, $this->config);
+            } else {
+                $localFileClass = $this->config->localFile;
+                if (is_a($localFileClass, '\PHP_CodeSniffer\Files\LocalFile', true) === false) {
+                    throw new RuntimeException('Custom LocalFile class '.$localFileClass.' is not a subtype of PHP_CodeSniffer\Files\LocalFile.');
+                }
+
+                $this->files[$path] = new $localFileClass($path, $this->ruleset, $this->config);
+            }
         }
 
         return $this->files[$path];