Introduce SystemAgnosticSimpleRelativePathHelper

src/File/SystemAgnosticSimpleRelativePathHelper.php

@@ -0,0 +1,26 @@
+<?php declare(strict_types = 1);
+
+namespace PHPStan\File;
+
+use function str_starts_with;
+use function strlen;
+use function substr;
+
+class SystemAgnosticSimpleRelativePathHelper implements RelativePathHelper
+{
+
+	public function __construct(private FileHelper $fileHelper)
+	{
+	}
+
+	public function getRelativePath(string $filename): string
+	{
+		$cwd = $this->fileHelper->getWorkingDirectory();
+		if ($cwd !== '' && str_starts_with($filename, $cwd)) {
+			return substr($filename, strlen($cwd) + 1);
+		}
+
+		return $filename;
+	}
+
+}

src/Testing/TypeInferenceTestCase.php

@@ -12,7 +12,7 @@
 use PHPStan\DependencyInjection\Type\ParameterClosureTypeExtensionProvider;
 use PHPStan\DependencyInjection\Type\ParameterOutTypeExtensionProvider;
 use PHPStan\File\FileHelper;
-use PHPStan\File\RelativePathHelper;
+use PHPStan\File\SystemAgnosticSimpleRelativePathHelper;
 use PHPStan\Php\PhpVersion;
 use PHPStan\PhpDoc\PhpDocInheritanceResolver;
 use PHPStan\PhpDoc\StubPhpDocProvider;
@@ -146,8 +146,7 @@ public static function gatherAssertTypes(string $file): array
 	{
 		$fileHelper = self::getContainer()->getByType(FileHelper::class);
 
-		/** @var RelativePathHelper $relativePathHelper */
-		$relativePathHelper = self::getContainer()->getService('simpleRelativePathHelper');
+		$relativePathHelper = new SystemAgnosticSimpleRelativePathHelper($fileHelper);
 
 		$file = $fileHelper->normalizePath($file);