Add PHP linter

config/services.yaml

@@ -23,6 +23,7 @@ services:
         alias: 'Rector\Console\Application'
 
     Symfony\Component\Console\Descriptor\TextDescriptor: null
+    Symfony\Component\Process\PhpExecutableFinder: null
 
     # PhpParser - Parser
     PhpParser\ParserFactory: null

src/Console/Command/ProcessCommand.php

@@ -15,6 +15,7 @@ use Rector\Console\Shell;
 use Rector\Extension\ReportingExtensionRunner;
 use Rector\FileSystem\FilesFinder;
 use Rector\Guard\RectorGuard;
+use Rector\Linter\Linter;
 use Rector\PhpParser\NodeTraverser\RectorNodeTraverser;
 use Rector\Stubs\StubLoader;
 use Symfony\Component\Console\Input\InputArgument;
@@ -85,6 +86,11 @@ final class ProcessCommand extends AbstractCommand
      */
     private $paths = [];
 
+    /**
+     * @var Linter
+     */
+    private $linter;
+
     /**
      * @param string[] $paths
      * @param string[] $fileExtensions
@@ -100,6 +106,7 @@ final class ProcessCommand extends AbstractCommand
         ReportingExtensionRunner $reportingExtensionRunner,
         RectorNodeTraverser $rectorNodeTraverser,
         StubLoader $stubLoader,
+        Linter $linter,
         array $paths,
         array $fileExtensions
     ) {
@@ -114,9 +121,10 @@ final class ProcessCommand extends AbstractCommand
         $this->reportingExtensionRunner = $reportingExtensionRunner;
         $this->rectorNodeTraverser = $rectorNodeTraverser;
         $this->stubLoader = $stubLoader;
+        $this->paths = $paths;
+        $this->linter = $linter;
 
         parent::__construct();
-        $this->paths = $paths;
     }
 
     protected function configure(): void
@@ -203,6 +211,10 @@ final class ProcessCommand extends AbstractCommand
             $this->configuration->mustMatchGitDiff()
         );
 
+        foreach ($phpFileInfos as $phpFileInfo) {
+            $this->linter->lintFile($phpFileInfo);
+        }
+
         $this->additionalAutoloader->autoloadWithInputAndSource($input, $source);
 
         $this->rectorApplication->runOnFileInfos($phpFileInfos);

src/Exception/Linter/LintingException.php

@@ -0,0 +1,11 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Exception\Linter;
+
+use Exception;
+
+final class LintingException extends Exception
+{
+}

src/Linter/Linter.php

@@ -0,0 +1,43 @@
+<?php
+
+declare(strict_types=1);
+
+namespace Rector\Linter;
+
+use Rector\Exception\Linter\LintingException;
+use Symfony\Component\Process\PhpExecutableFinder;
+use Symfony\Component\Process\Process;
+use Symplify\SmartFileSystem\SmartFileInfo;
+
+/**
+ * Inspired by https://github.com/keradus/PHP-CS-Fixer/blob/a838434c7584e4744e2fca9950687d5326212560/Symfony/CS/Linter/Linter.php
+ */
+final class Linter
+{
+    /**
+     * @var string
+     */
+    private $executable;
+
+    public function __construct(PhpExecutableFinder $phpExecutableFinder)
+    {
+        $executable = $phpExecutableFinder->find();
+        if ($executable === false) {
+            throw new LintingException('PHP executable was not found');
+        }
+
+        $this->executable = $executable;
+    }
+
+    public function lintFile(SmartFileInfo $smartFileInfo): void
+    {
+        $process = new Process([$this->executable, '-l', $smartFileInfo->getRealPath()]);
+        $process->run();
+
+        if ($process->isSuccessful()) {
+            return;
+        }
+
+        throw new LintingException($process->getOutput(), (int) $process->getExitCode());
+    }
+}