Improve type safety

Author: sebastianbergmann

.psalm/baseline.xml

@@ -4,8 +4,5 @@
     <MissingTemplateParam>
       <code>Iterator</code>
     </MissingTemplateParam>
-    <PossiblyFalseArgument>
-      <code>$this-&gt;basePath</code>
-    </PossiblyFalseArgument>
   </file>
 </files>

src/Facade.php

@@ -20,6 +20,10 @@
 final class Facade
 {
     /**
+     * @psalm-param list<string>|string $suffixes
+     * @psalm-param list<string>|string $prefixes
+     * @psalm-param list<string> $exclude
+     *
      * @psalm-return list<string>
      */
     public function getFilesAsArray(string $path, array|string $suffixes = '', array|string $prefixes = '', array $exclude = []): array

src/Factory.php

@@ -13,6 +13,7 @@
 use function array_filter;
 use function array_map;
 use function array_merge;
+use function array_values;
 use function glob;
 use function is_dir;
 use function is_string;
@@ -27,6 +28,12 @@
  */
 final class Factory
 {
+    /**
+     * @psalm-param list<string>|string $paths
+     * @psalm-param list<string>|string $suffixes
+     * @psalm-param list<string>|string $prefixes
+     * @psalm-param list<string> $exclude
+     */
     public function getFileIterator(array|string $paths, array|string $suffixes = '', array|string $prefixes = '', array $exclude = []): AppendIterator
     {
         if (is_string($paths)) {
@@ -73,6 +80,11 @@ public function getFileIterator(array|string $paths, array|string $suffixes = ''
         return $iterator;
     }
 
+    /**
+     * @psalm-param list<string> $paths
+     *
+     * @psalm-return list<string>
+     */
     private function resolveWildcards(array $paths): array
     {
         $_paths = [[]];
@@ -87,6 +99,6 @@ private function resolveWildcards(array $paths): array
             }
         }
 
-        return array_filter(array_merge(...$_paths));
+        return array_values(array_filter(array_merge(...$_paths)));
     }
 }

src/Iterator.php

@@ -11,12 +11,15 @@
 
 use function array_filter;
 use function array_map;
+use function array_values;
+use function assert;
 use function preg_match;
 use function realpath;
 use function str_ends_with;
 use function str_replace;
 use function str_starts_with;
 use FilterIterator;
+use SplFileInfo;
 
 /**
  * @internal This class is not covered by the backward compatibility promise for phpunit/php-file-iterator
@@ -27,23 +30,43 @@ final class Iterator extends FilterIterator
 
     public const SUFFIX = 1;
     private string|false $basePath;
+
+    /**
+     * @psalm-var list<string>
+     */
     private array $suffixes;
+
+    /**
+     * @psalm-var list<string>
+     */
     private array $prefixes;
+
+    /**
+     * @psalm-var list<string>
+     */
     private array $exclude;
 
+    /**
+     * @psalm-param list<string> $suffixes
+     * @psalm-param list<string> $prefixes
+     * @psalm-param list<string> $exclude
+     */
     public function __construct(string $basePath, \Iterator $iterator, array $suffixes = [], array $prefixes = [], array $exclude = [])
     {
         $this->basePath = realpath($basePath);
         $this->prefixes = $prefixes;
         $this->suffixes = $suffixes;
-        $this->exclude  = array_filter(array_map('realpath', $exclude));
+        $this->exclude  = array_values(array_filter(array_map('realpath', $exclude)));
 
         parent::__construct($iterator);
     }
 
     public function accept(): bool
     {
-        $current  = $this->getInnerIterator()->current();
+        $current = $this->getInnerIterator()->current();
+
+        assert($current instanceof SplFileInfo);
+
         $filename = $current->getFilename();
         $realPath = $current->getRealPath();
 
@@ -61,7 +84,7 @@ public function accept(): bool
     private function acceptPath(string $path): bool
     {
         // Filter files in hidden directories by checking path that is relative to the base path.
-        if (preg_match('=/\.[^/]*/=', str_replace($this->basePath, '', $path))) {
+        if (preg_match('=/\.[^/]*/=', str_replace((string) $this->basePath, '', $path))) {
             return false;
         }
 
@@ -84,6 +107,9 @@ private function acceptSuffix(string $filename): bool
         return $this->acceptSubString($filename, $this->suffixes, self::SUFFIX);
     }
 
+    /**
+     * @psalm-param list<string> $subStrings
+     */
     private function acceptSubString(string $filename, array $subStrings, int $type): bool
     {
         if (empty($subStrings)) {