Add --dirty option to process only Git-dirty files in Rector

src/Configuration/ConfigurationFactory.php

@@ -5,6 +5,7 @@
 
 use Rector\ChangesReporting\Output\ConsoleOutputFormatter;
 use Rector\Configuration\Parameter\SimpleParameterProvider;
+use Rector\FileSystem\GitDirtyFileFetcher;
 use Rector\ValueObject\Configuration;
 use RectorPrefix202511\Symfony\Component\Console\Input\InputInterface;
 use RectorPrefix202511\Symfony\Component\Console\Style\SymfonyStyle;
@@ -97,6 +98,12 @@ private function resolvePaths(InputInterface $input): array
             $this->setFilesWithoutExtensionParameter($commandLinePaths);
             return $commandLinePaths;
         }
+
+        $optionDirty = (bool) $input->getOption(\Rector\Configuration\Option::DIRTY);
+        if ($optionDirty) {
+            return (new GitDirtyFileFetcher())->fetchDirtyFiles();
+        }
+
         // fallback to parameter
         $configPaths = SimpleParameterProvider::provideArrayParameter(\Rector\Configuration\Option::PATHS);
         $this->setFilesWithoutExtensionParameter($configPaths);

src/Configuration/Option.php

@@ -143,6 +143,10 @@ final class Option
      * @var string
      */
     public const NO_DIFFS = 'no-diffs';
+    /**
+     * @var string
+     */
+    public const DIRTY = 'dirty';
     /**
      * @var string
      */

src/Console/ProcessConfigureDecorator.php

@@ -27,5 +27,6 @@ public static function decorate(Command $command): void
         $command->addOption(Option::PARALLEL_PORT, null, InputOption::VALUE_REQUIRED);
         $command->addOption(Option::PARALLEL_IDENTIFIER, null, InputOption::VALUE_REQUIRED);
         $command->addOption(Option::XDEBUG, null, InputOption::VALUE_NONE, 'Display xdebug output.');
+        $command->addOption(Option::DIRTY, null, InputOption::VALUE_NONE, 'Only process files with uncommitted changes according to Git (git status --porcelain)');
     }
 }

src/FileSystem/GitDirtyFileFetcher.php

@@ -0,0 +1,96 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\FileSystem;
+
+use function array_filter;
+use function explode;
+use function is_file;
+use function strlen;
+use function substr;
+use function trim;
+
+final class GitDirtyFileFetcher
+{
+    /**
+     * A callable that accepts a command string and returns an array of output lines,
+     * or a string. By default null -> uses exec().
+     *
+     * @var callable|null
+     */
+    private $commandRunner;
+
+    /**
+     * @param callable|null $commandRunner signature: fn(string $cmd): array|string
+     */
+    public function __construct(?callable $commandRunner = null)
+    {
+        $this->commandRunner = $commandRunner;
+    }
+
+    /**
+     * Return relative file paths reported by `git status --porcelain`.
+     *
+     * - includes modified (M), added (A), untracked (??) files
+     * - strips the two-character status prefix and whitespace
+     *
+     * @return string[] relative paths
+     */
+    public function fetchDirtyFiles(): array
+    {
+        $lines = $this->runCommand('git status --porcelain');
+
+        $files = [];
+
+        foreach ($lines as $line) {
+            $line = (string)$line;
+            if (trim($line) === '') {
+                continue;
+            }
+
+            // porcelain format: two-char status  space  path (path can include spaces)
+            // e.g. " M src/Service/Foo.php", "?? newfile.php"
+            if (strlen($line) <= 3) {
+                continue;
+            }
+
+            $path = trim(substr($line, 3));
+
+            if ($path === '') {
+                continue;
+            }
+
+            // prefer files on disk to avoid passing directories
+            if (is_file($path)) {
+                $files[] = $path;
+            }
+        }
+
+        // remove duplicates and empty entries
+        $files = array_filter($files);
+
+        return array_values($files);
+    }
+
+    /**
+     * @return string[] lines
+     */
+    private function runCommand(string $command): array
+    {
+        if ($this->commandRunner !== null) {
+            $result = ($this->commandRunner)($command);
+            if (is_array($result)) {
+                return $result;
+            }
+            if (is_string($result)) {
+                return explode("\n", $result);
+            }
+            return [];
+        }
+
+        $output = [];
+        @exec($command, $output);
+        return $output;
+    }
+}