Add directory filter

src/DirectoryFilter.php

@@ -0,0 +1,60 @@
+<?php
+/**
+ * Copyright (c) 2015 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Licensed under the MIT license:
+ * http://opensource.org/licenses/MIT
+ */
+
+namespace Icewind\Streams;
+
+/**
+ * Wrapper allows filtering of directories
+ *
+ * The filter callback will be called for each entry in the folder
+ * when the callback return false the entry will be filtered out
+ */
+class DirectoryFilter extends DirectoryWrapper {
+	/**
+	 * @var callable
+	 */
+	private $filter;
+
+	/**
+	 * @param string $path
+	 * @param array $options
+	 * @return bool
+	 */
+	public function dir_opendir($path, $options) {
+		$context = $this->loadContext('filter');
+		$this->filter = $context['filter'];
+		return true;
+	}
+
+	/**
+	 * @return string
+	 */
+	public function dir_readdir() {
+		$file = readdir($this->source);
+		$filter = $this->filter;
+		// keep reading untill we have an accepted entry or we're at the end of the folder
+		while ($file !== false && $filter($file) === false) {
+			$file = readdir($this->source);
+		}
+		return $file;
+	}
+
+	/**
+	 * @param resource $source
+	 * @param callable $filter
+	 * @return resource
+	 */
+	public static function wrap($source, callable $filter) {
+		$options = array(
+			'filter' => array(
+				'source' => $source,
+				'filter' => $filter
+			)
+		);
+		return self::wrapWithOptions($options);
+	}
+}

src/DirectoryWrapper.php

@@ -73,22 +73,6 @@ class DirectoryWrapper implements Directory {
 		return true;
 	}
 
-	/**
-	 * Creates a directory handle from the provided array or iterator
-	 *
-	 * @param resource $source
-	 * @return resource
-	 *
-	 * @throws \BadMethodCallException
-	 */
-	public static function wrap($source) {
-		$options = array(
-			'dir' => array(
-				'source' => $source)
-		);
-		return self::wrapWithOptions($options);
-	}
-
 	/**
 	 * @param string $options the options for the context to wrap the stream with
 	 * @return resource

tests/DirectoryFilter.php

@@ -0,0 +1,44 @@
+<?php
+/**
+ * Copyright (c) 2015 Robin Appelman <icewind@owncloud.com>
+ * This file is licensed under the Licensed under the MIT license:
+ * http://opensource.org/licenses/MIT
+ */
+
+namespace Icewind\Streams\Tests;
+
+class DirectoryFilter extends \PHPUnit_Framework_TestCase {
+	public function testFilterAcceptAll() {
+		$this->filter(['a', 'b', 'c'],
+			function () {
+				return true;
+			},
+			['a', 'b', 'c']);
+	}
+
+	public function testFilterRejectAll() {
+		$this->filter(['a', 'b', 'c'],
+			function () {
+				return false;
+			},
+			[]);
+	}
+
+	public function testFilterRejectLong() {
+		$this->filter(['a', 'bb', 'c'],
+			function ($file) {
+				return strlen($file) < 2;
+			},
+			['a', 'c']);
+	}
+
+	private function filter(array $files, callable $filter, array $expected) {
+		$source = \Icewind\Streams\IteratorDirectory::wrap($files);
+		$filtered = \Icewind\Streams\DirectoryFilter::wrap($source, $filter);
+		$result = [];
+		while (($file = readdir($filtered)) !== false) {
+			$result[] = $file;
+		}
+		$this->assertEquals($expected, $result);
+	}
+}

tests/DirectoryWrapper.php

@@ -8,6 +8,14 @@
 namespace Icewind\Streams\Tests;
 
 class DirectoryWrapperDummy extends \Icewind\Streams\DirectoryWrapper {
+	public static function wrap($source) {
+		$options = array(
+			'dir' => array(
+				'source' => $source)
+		);
+		return self::wrapWithOptions($options);
+	}
+
 	public function dir_readdir() {
 		$file = parent::dir_readdir();
 		if ($file !== false) {