Fix bogus deletion on copy + unlink through rename

Cross-storage rename would cause copy + unlink. That unlink operation
must not trigger the trashbin.

apps/files_trashbin/lib/storage.php

@@ -33,12 +33,43 @@ class Storage extends Wrapper {
 	// move files across storages
 	private $deletedFiles = array();
 
+	/**
+	 * Disable trash logic
+	 *
+	 * @var bool
+	 */
+	private static $disableTrash = false;
+
 	function __construct($parameters) {
 		$this->mountPoint = $parameters['mountPoint'];
 		parent::__construct($parameters);
 	}
 
+	/**
+	 * @internal
+	 */
+	public static function preRenameHook($params) {
+		// in cross-storage cases, a rename is a copy + unlink,
+		// that last unlink must not go to trash
+		self::$disableTrash = true;
+	}
+
+	/**
+	 * @internal
+	 */
+	public static function postRenameHook($params) {
+		self::$disableTrash = false;
+	}
+
+	/**
+	 * Deletes the given file by moving it into the trashbin.
+	 *
+	 * @param string $path
+	 */
 	public function unlink($path) {
+		if (self::$disableTrash) {
+			return $this->storage->unlink($path);
+		}
 		$normalized = Filesystem::normalizePath($this->mountPoint . '/' . $path);
 		$result = true;
 		if (!isset($this->deletedFiles[$normalized])) {

apps/files_trashbin/lib/trashbin.php

@@ -928,6 +928,9 @@ class Trashbin {
 		\OCP\Util::connectHook('OC_User', 'pre_deleteUser', 'OCA\Files_Trashbin\Hooks', 'deleteUser_hook');
 		//Listen to post write hook
 		\OCP\Util::connectHook('OC_Filesystem', 'post_write', 'OCA\Files_Trashbin\Hooks', 'post_write_hook');
+		// pre and post-rename, disable trash logic for the copy+unlink case
+		\OCP\Util::connectHook('OC_Filesystem', 'rename', 'OCA\Files_Trashbin\Storage', 'preRenameHook');
+		\OCP\Util::connectHook('OC_Filesystem', 'post_rename', 'OCA\Files_Trashbin\Storage', 'postRenameHook');
 	}
 
 	/**

apps/files_trashbin/tests/storage.php

@@ -37,6 +37,9 @@ class Storage extends \Test\TestCase {
 	protected function setUp() {
 		parent::setUp();
 
+		\OC_Hook::clear();
+		\OCA\Files_Trashbin\Trashbin::registerHooks();
+
 		$this->user = $this->getUniqueId('user');
 		\OC::$server->getUserManager()->createUser($this->user, $this->user);
 
@@ -58,6 +61,7 @@ class Storage extends \Test\TestCase {
 		\OC\Files\Filesystem::mount($this->originalStorage, array(), '/');
 		$this->logout();
 		\OC_User::deleteUser($this->user);
+		\OC_Hook::clear();
 		parent::tearDown();
 	}