Merge pull request #11363 from owncloud/sharing_group_shares_stable7

Sharing group shares stable7

14 files changed, 741 insertions, 429 deletions

diff --git a/apps/files_sharing/appinfo/app.php b/apps/files_sharing/appinfo/app.php
index b22c553ec93..ec429529887 100644
--- a/apps/files_sharing/appinfo/app.php
+++ b/apps/files_sharing/appinfo/app.php
@@ -12,6 +12,9 @@ OC::$CLASSPATH['OCA\Files\Share\Api'] = 'files_sharing/lib/api.php';
 OC::$CLASSPATH['OCA\Files\Share\Maintainer'] = 'files_sharing/lib/maintainer.php';
 OC::$CLASSPATH['OCA\Files\Share\Proxy'] = 'files_sharing/lib/proxy.php';
 
+// Exceptions
+OC::$CLASSPATH['OCA\Files_Sharing\Exceptions\BrokenPath'] = 'files_sharing/lib/exceptions.php';
+
 \OCP\App::registerAdmin('files_sharing', 'settings-admin');
 
 \OCA\Files_Sharing\Helper::registerHooks();
diff --git a/apps/files_sharing/lib/exceptions.php b/apps/files_sharing/lib/exceptions.php
new file mode 100644
index 00000000000..2a57a69a95f
--- /dev/null
+++ b/apps/files_sharing/lib/exceptions.php
@@ -0,0 +1,32 @@
+<?php
+/**
+ * ownCloud
+ *
+ * @author Bjoern Schiessle
+ * @copyright 2014 Bjoern Schiessle <schiessle@owncloud.com>
+ *
+ * This library is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU AFFERO GENERAL PUBLIC LICENSE
+ * License as published by the Free Software Foundation; either
+ * version 3 of the License, or any later version.
+ *
+ * This library is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU AFFERO GENERAL PUBLIC LICENSE for more details.
+ *
+ * You should have received a copy of the GNU Affero General Public
+ * License along with this library.  If not, see <http://www.gnu.org/licenses/>.
+ *
+ */
+
+namespace OCA\Files_Sharing\Exceptions;
+
+/**
+ * Expected path with a different root
+ * Possible Error Codes:
+ * 10 - Path not relative to data/ and point to the users file directory
+
+ */
+class BrokenPath extends \Exception {
+}
diff --git a/apps/files_sharing/lib/share/file.php b/apps/files_sharing/lib/share/file.php
index 2ae7fdc16ab..dacdb9308be 100644
--- a/apps/files_sharing/lib/share/file.php
+++ b/apps/files_sharing/lib/share/file.php
@@ -38,7 +38,7 @@ class OC_Share_Backend_File implements OCP\Share_Backend_File_Dependent {
 			// FIXME: attributes should not be set here,
 			// keeping this pattern for now to avoid unexpected
 			// regressions
-			$this->path = basename($path);
+			$this->path = \OC\Files\Filesystem::normalizePath(basename($path));
 			return true;
 		}
 		return false;
@@ -57,7 +57,7 @@ class OC_Share_Backend_File implements OCP\Share_Backend_File_Dependent {
 	 * create unique target
 	 * @param string $filePath
 	 * @param string $shareWith
-	 * @param string $exclude
+	 * @param array $exclude (optional)
 	 * @return string
 	 */
 	public function generateTarget($filePath, $shareWith, $exclude = null) {
@@ -83,10 +83,7 @@ class OC_Share_Backend_File implements OCP\Share_Backend_File_Dependent {
 			}
 		}
 
-		$excludeList = \OCP\Share::getItemsSharedWithUser('file', $shareWith, self::FORMAT_TARGET_NAMES);
-		if (is_array($exclude)) {
-			$excludeList = array_merge($excludeList, $exclude);
-		}
+		$excludeList = (is_array($exclude)) ? $exclude : array();
 
 		return \OCA\Files_Sharing\Helper::generateUniqueTarget($target, $excludeList, $view);
 	}
diff --git a/apps/files_sharing/lib/sharedmount.php b/apps/files_sharing/lib/sharedmount.php
index 564ac43ec74..4ad2d4e6b3e 100644
--- a/apps/files_sharing/lib/sharedmount.php
+++ b/apps/files_sharing/lib/sharedmount.php
@@ -58,7 +58,7 @@ class SharedMount extends Mount implements MoveableMount {
 	 * update fileTarget in the database if the mount point changed
 	 * @param string $newPath
 	 * @param array $share reference to the share which should be modified
-	 * @return type
+	 * @return bool
 	 */
 	private static function updateFileTarget($newPath, &$share) {
 		// if the user renames a mount point from a group share we need to create a new db entry
@@ -91,7 +91,7 @@ class SharedMount extends Mount implements MoveableMount {
 	 * @param string $path the absolute path
 	 * @return string e.g. turns '/admin/files/test.txt' into '/test.txt'
 	 */
-	private function stripUserFilesPath($path) {
+	protected function stripUserFilesPath($path) {
 		$trimmed = ltrim($path, '/');
 		$split = explode('/', $trimmed);
 
@@ -99,8 +99,8 @@ class SharedMount extends Mount implements MoveableMount {
 		if (count($split) < 3 || $split[1] !== 'files') {
 			\OCP\Util::writeLog('file sharing',
 				'Can not strip userid and "files/" from path: ' . $path,
-				\OCP\Util::DEBUG);
-			return false;
+				\OCP\Util::ERROR);
+			throw new \OCA\Files_Sharing\Exceptions\BrokenPath('Path does not start with /user/files', 10);
 		}
 
 		// skip 'user' and 'files'
@@ -121,7 +121,15 @@ class SharedMount extends Mount implements MoveableMount {
 		$relTargetPath = $this->stripUserFilesPath($target);
 		$share = $this->storage->getShare();
 
-		$result = $this->updateFileTarget($relTargetPath, $share);
+		$result = true;
+
+		if (!empty($share['grouped'])) {
+			foreach ($share['grouped'] as $s) {
+				$result = $this->updateFileTarget($relTargetPath, $s) && $result;
+			}
+		} else {
+			$result = $this->updateFileTarget($relTargetPath, $share) && $result;
+		}
 
 		if ($result) {
 			$this->setMountPoint($target);
@@ -144,8 +152,9 @@ class SharedMount extends Mount implements MoveableMount {
 	 */
 	public function removeMount() {
 		$mountManager = \OC\Files\Filesystem::getMountManager();
+		/** @var \OC\Files\Storage\Shared */
 		$storage = $this->getStorage();
-		$result =  \OCP\Share::unshareFromSelf($storage->getItemType(), $storage->getMountPoint());
+		$result = $storage->unshareStorage();
 		$mountManager->removeMount($this->mountPoint);
 
 		return $result;
diff --git a/apps/files_sharing/lib/sharedstorage.php b/apps/files_sharing/lib/sharedstorage.php
index 02fcd7041dd..dc161616110 100644
--- a/apps/files_sharing/lib/sharedstorage.php
+++ b/apps/files_sharing/lib/sharedstorage.php
@@ -532,4 +532,21 @@ class Shared extends \OC\Files\Storage\Common implements ISharedStorage {
 		return null;
 	}
 
+	/**
+	 * unshare complete storage, also the grouped shares
+	 *
+	 * @return bool
+	 */
+	public function unshareStorage() {
+		$result = true;
+		if (!empty($this->share['grouped'])) {
+			foreach ($this->share['grouped'] as $share) {
+				$result = $result && \OCP\Share::unshareFromSelf($share['item_type'], $share['file_target']);
+			}
+		}
+		$result = $result && \OCP\Share::unshareFromSelf($this->getItemType(), $this->getMountPoint());
+
+		return $result;
+	}
+
 }
diff --git a/apps/files_sharing/tests/base.php b/apps/files_sharing/tests/base.php
index 34ec4a36ede..738ba3493ba 100644
--- a/apps/files_sharing/tests/base.php
+++ b/apps/files_sharing/tests/base.php
@@ -35,6 +35,8 @@ abstract class Test_Files_Sharing_Base extends \PHPUnit_Framework_TestCase {
 	const TEST_FILES_SHARING_API_USER2 = "test-share-user2";
 	const TEST_FILES_SHARING_API_USER3 = "test-share-user3";
 
+	const TEST_FILES_SHARING_API_GROUP1 = "test-share-group1";
+
 	public $stateFilesEncryption;
 	public $filename;
 	public $data;
@@ -60,6 +62,10 @@ abstract class Test_Files_Sharing_Base extends \PHPUnit_Framework_TestCase {
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER2, true);
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER3, true);
 
+		// create group
+		\OC_Group::createGroup(self::TEST_FILES_SHARING_API_GROUP1);
+		\OC_Group::addToGroup(self::TEST_FILES_SHARING_API_USER2, self::TEST_FILES_SHARING_API_GROUP1);
+
 	}
 
 	function setUp() {
@@ -86,6 +92,9 @@ abstract class Test_Files_Sharing_Base extends \PHPUnit_Framework_TestCase {
 		} else {
 			\OC_App::disable('files_encryption');
 		}
+
+		$query = \OCP\DB::prepare('DELETE FROM `*PREFIX*share`');
+		$query->execute();
 	}
 
 	public static function tearDownAfterClass() {
@@ -94,6 +103,9 @@ abstract class Test_Files_Sharing_Base extends \PHPUnit_Framework_TestCase {
 		\OC_User::deleteUser(self::TEST_FILES_SHARING_API_USER1);
 		\OC_User::deleteUser(self::TEST_FILES_SHARING_API_USER2);
 		\OC_User::deleteUser(self::TEST_FILES_SHARING_API_USER3);
+
+		// delete group
+		\OC_Group::deleteGroup(self::TEST_FILES_SHARING_API_GROUP1);
 	}
 
 	/**
diff --git a/apps/files_sharing/tests/share.php b/apps/files_sharing/tests/share.php
index 31246c5df44..fe80cfca781 100644
--- a/apps/files_sharing/tests/share.php
+++ b/apps/files_sharing/tests/share.php
@@ -57,6 +57,10 @@ class Test_Files_Sharing extends Test_Files_Sharing_Base {
 
 		self::$tempStorage = null;
 
+		// clear database table
+		$query = \OCP\DB::prepare('DELETE FROM `*PREFIX*share`');
+		$query->execute();
+
 		parent::tearDown();
 	}
 
@@ -68,10 +72,6 @@ class Test_Files_Sharing extends Test_Files_Sharing_Base {
 
 		$fileinfo = $this->view->getFileInfo($this->filename);
 
-		$pathinfo = pathinfo($this->filename);
-
-		$duplicate = '/' . $pathinfo['filename'] . ' (2).' . $pathinfo['extension'];
-
 		$result = \OCP\Share::shareItem('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
 				\Test_Files_Sharing::TEST_FILES_SHARING_API_USER2, 31);
 
@@ -84,47 +84,146 @@ class Test_Files_Sharing extends Test_Files_Sharing_Base {
 
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER2);
 		$this->assertTrue(\OC\Files\Filesystem::file_exists($this->filename));
-		$this->assertTrue(\OC\Files\Filesystem::file_exists($duplicate));
 
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER3);
 		$this->assertTrue(\OC\Files\Filesystem::file_exists($this->filename));
-		$this->assertFalse(\OC\Files\Filesystem::file_exists($duplicate));
 
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER2);
 		\OC\Files\Filesystem::unlink($this->filename);
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER2);
+		// both group share and user share should be gone
 		$this->assertFalse(\OC\Files\Filesystem::file_exists($this->filename));
-		$this->assertTrue(\OC\Files\Filesystem::file_exists($duplicate));
 
 		// for user3 nothing should change
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER3);
 		$this->assertTrue(\OC\Files\Filesystem::file_exists($this->filename));
-		$this->assertFalse(\OC\Files\Filesystem::file_exists($duplicate));
+	}
+
+	/**
+	 * if a file was shared as group share and as individual share they should be grouped
+	 */
+	function testGroupingOfShares() {
+
+		$fileinfo = $this->view->getFileInfo($this->filename);
+
+		$result = \OCP\Share::shareItem('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_GROUP,
+				\Test_Files_Sharing::TEST_FILES_SHARING_API_GROUP1, \OCP\PERMISSION_READ);
+
+		$this->assertTrue($result);
+
+		$result = \OCP\Share::shareItem('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
+				\Test_Files_Sharing::TEST_FILES_SHARING_API_USER2, \OCP\PERMISSION_UPDATE);
+
+		$this->assertTrue($result);
 
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER2);
-		\OC\Files\Filesystem::unlink($duplicate);
-		self::loginHelper(self::TEST_FILES_SHARING_API_USER2);
-		$this->assertFalse(\OC\Files\Filesystem::file_exists($this->filename));
-		$this->assertFalse(\OC\Files\Filesystem::file_exists($duplicate));
 
-		// for user3 nothing should change
-		self::loginHelper(self::TEST_FILES_SHARING_API_USER3);
-		$this->assertTrue(\OC\Files\Filesystem::file_exists($this->filename));
-		$this->assertFalse(\OC\Files\Filesystem::file_exists($duplicate));
+		$result = \OCP\Share::getItemSharedWith('file', null);
+
+		$this->assertTrue(is_array($result));
+
+		// test should return exactly one shares created from testCreateShare()
+		$this->assertSame(1, count($result));
+
+		$share = reset($result);
+		$this->assertSame(\OCP\PERMISSION_READ | \OCP\PERMISSION_UPDATE, $share['permissions']);
+
+		\OC\Files\Filesystem::rename($this->filename, $this->filename . '-renamed');
+
+		$result = \OCP\Share::getItemSharedWith('file', null);
+
+		$this->assertTrue(is_array($result));
+
+		// test should return exactly one shares created from testCreateShare()
+		$this->assertSame(1, count($result));
+
+		$share = reset($result);
+		$this->assertSame(\OCP\PERMISSION_READ | \OCP\PERMISSION_UPDATE, $share['permissions']);
+		$this->assertSame($this->filename . '-renamed', $share['file_target']);
 
-		//cleanup
 		self::loginHelper(self::TEST_FILES_SHARING_API_USER1);
-		\OCP\Share::unshare('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_GROUP,
-				'testGroup');
-		\OCP\Share::unshare('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
-				self::TEST_FILES_SHARING_API_USER2);
-		\OC_Group::removeFromGroup(self::TEST_FILES_SHARING_API_USER2, 'testGroup');
-		\OC_Group::removeFromGroup(self::TEST_FILES_SHARING_API_USER2, 'testGroup');
-		\OC_Group::deleteGroup('testGroup');
 
+		// unshare user share
+		$result = \OCP\Share::unshare('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
+				\Test_Files_Sharing::TEST_FILES_SHARING_API_USER2);
+		$this->assertTrue($result);
+
+		self::loginHelper(self::TEST_FILES_SHARING_API_USER2);
+
+		$result = \OCP\Share::getItemSharedWith('file', null);
+
+		$this->assertTrue(is_array($result));
+
+		// test should return the remaining group share
+		$this->assertSame(1, count($result));
+
+		$share = reset($result);
+		// only the group share permissions should be available now
+		$this->assertSame(\OCP\PERMISSION_READ, $share['permissions']);
+		$this->assertSame($this->filename . '-renamed', $share['file_target']);
 
 	}
 
+	/**
+	 * user1 share file to a group and to a user2 in the same group. Then user2
+	 * unshares the file from self. Afterwards user1 should no longer see the
+	 * single user share to user2. If he re-shares the file to user2 the same target
+	 * then the group share should be used to group the item
+	 */
+	function testShareAndUnshareFromSelf() {
+		$fileinfo = $this->view->getFileInfo($this->filename);
+
+		// share the file to group1 (user2 is a member of this group) and explicitely to user2
+		\OCP\Share::shareItem('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_GROUP, self::TEST_FILES_SHARING_API_GROUP1, \OCP\PERMISSION_ALL);
+		\OCP\Share::shareItem('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER, self::TEST_FILES_SHARING_API_USER2, \OCP\PERMISSION_ALL);
+
+		// user1 should have to shared files
+		$shares = \OCP\Share::getItemsShared('file');
+		$this->assertSame(2, count($shares));
+
+		// user2 should have two files "welcome.txt" and the shared file,
+		// both the group share and the single share of the same file should be
+		// grouped to one file
+		\Test_Files_Sharing::loginHelper(self::TEST_FILES_SHARING_API_USER2);
+		$dirContent = \OC\Files\Filesystem::getDirectoryContent('/');
+		$this->assertSame(2, count($dirContent));
+		$this->verifyDirContent($dirContent, array('welcome.txt', ltrim($this->filename, '/')));
+
+		// now user2 deletes the share (= unshare from self)
+		\OC\Files\Filesystem::unlink($this->filename);
+
+		// only welcome.txt should exists
+		$dirContent = \OC\Files\Filesystem::getDirectoryContent('/');
+		$this->assertSame(1, count($dirContent));
+		$this->verifyDirContent($dirContent, array('welcome.txt'));
+
+		// login as user1...
+		\Test_Files_Sharing::loginHelper(self::TEST_FILES_SHARING_API_USER1);
+
+		// ... now user1 should have only one shared file, the group share
+		$shares = \OCP\Share::getItemsShared('file');
+		$this->assertSame(1, count($shares));
+
+		// user1 shares a gain the file directly to user2
+		\OCP\Share::shareItem('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER, self::TEST_FILES_SHARING_API_USER2, \OCP\PERMISSION_ALL);
+
+		// user2 should see again welcome.txt and the shared file
+		\Test_Files_Sharing::loginHelper(self::TEST_FILES_SHARING_API_USER2);
+		$dirContent = \OC\Files\Filesystem::getDirectoryContent('/');
+		$this->assertSame(2, count($dirContent));
+		$this->verifyDirContent($dirContent, array('welcome.txt', ltrim($this->filename, '/')));
+
+
+	}
+
+	function verifyDirContent($content, $expected) {
+		foreach ($content as $c) {
+			if (!in_array($c['name'], $expected)) {
+				$this->assertTrue(false, "folder should only contain '" . implode(',', $expected) . "', found: " .$c['name']);
+			}
+		}
+	}
+
 	function testShareWithDifferentShareFolder() {
 
 		$fileinfo = $this->view->getFileInfo($this->filename);
@@ -146,12 +245,6 @@ class Test_Files_Sharing extends Test_Files_Sharing_Base {
 		$this->assertTrue(\OC\Files\Filesystem::file_exists('/Shared/subfolder/' . $this->folder));
 
 		//cleanup
-		self::loginHelper(self::TEST_FILES_SHARING_API_USER1);
-		\OCP\Share::unshare('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
-				self::TEST_FILES_SHARING_API_USER2);
-		\OCP\Share::unshare('folder', $folderinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
-				self::TEST_FILES_SHARING_API_USER2);
-
 		\OCP\Config::deleteSystemValue('share_folder');
 	}
 
@@ -173,18 +266,14 @@ class Test_Files_Sharing extends Test_Files_Sharing_Base {
 		$this->assertTrue(is_array($result));
 
 		// test should return exactly one shares created from testCreateShare()
-		$this->assertTrue(count($result) === 1);
+		$this->assertSame(1, count($result), 'more then one share found');
 
 		$share = reset($result);
 		$this->assertSame($expectedPermissions, $share['permissions']);
-
-		\OCP\Share::unshare('file', $fileinfo['fileid'], \OCP\Share::SHARE_TYPE_USER,
-				\Test_Files_Sharing::TEST_FILES_SHARING_API_USER2);
 	}
 
 	function DataProviderTestFileSharePermissions() {
 		$permission1 = \OCP\PERMISSION_ALL;
-		$permission2 = \OCP\PERMISSION_DELETE;
 		$permission3 = \OCP\PERMISSION_READ;
 		$permission4 = \OCP\PERMISSION_READ | \OCP\PERMISSION_UPDATE;
 		$permission5 = \OCP\PERMISSION_READ | \OCP\PERMISSION_DELETE;
@@ -192,7 +281,6 @@ class Test_Files_Sharing extends Test_Files_Sharing_Base {
 
 		return array(
 			array($permission1, \OCP\PERMISSION_ALL & ~\OCP\PERMISSION_DELETE),
-			array($permission2, 0),
 			array($permission3, $permission3),
 			array($permission4, $permission4),
 			array($permission5, $permission3),
diff --git a/apps/files_sharing/tests/sharedmount.php b/apps/files_sharing/tests/sharedmount.php
index f8c65734184..ac910944f9f 100644
--- a/apps/files_sharing/tests/sharedmount.php
+++ b/apps/files_sharing/tests/sharedmount.php
@@ -194,4 +194,41 @@ class Test_Files_Sharing_Mount extends Test_Files_Sharing_Base {
 		\OC_Group::removeFromGroup(self::TEST_FILES_SHARING_API_USER3, 'testGroup');
 	}
 
+	/**
+	 * @dataProvider dataProviderTestStripUserFilesPath
+	 * @param string $path
+	 * @param string $expectedResult
+	 * @param bool $exception if a exception is expected
+	 */
+	function testStripUserFilesPath($path, $expectedResult, $exception) {
+		$testClass = new DummyTestClassSharedMount(null, null);
+		try {
+			$result = $testClass->stripUserFilesPathDummy($path);
+			$this->assertSame($expectedResult, $result);
+		} catch (\Exception $e) {
+			if ($exception) {
+				$this->assertSame(10, $e->getCode());
+			} else {
+				$this->assertTrue(false, "Exception catched, but expected: " . $expectedResult);
+			}
+		}
+	}
+
+	function dataProviderTestStripUserFilesPath() {
+		return array(
+			array('/user/files/foo.txt', '/foo.txt', false),
+			array('/user/files/folder/foo.txt', '/folder/foo.txt', false),
+			array('/data/user/files/foo.txt', null, true),
+			array('/data/user/files/', null, true),
+			array('/files/foo.txt', null, true),
+			array('/foo.txt', null, true),
+		);
+	}
+
+}
+
+class DummyTestClassSharedMount extends \OCA\Files_Sharing\SharedMount {
+	public function stripUserFilesPathDummy($path) {
+		return $this->stripUserFilesPath($path);
+	}
 }
diff --git a/lib/private/share/helper.php b/lib/private/share/helper.php
index 46e3c280488..2418535c9d5 100644
--- a/lib/private/share/helper.php
+++ b/lib/private/share/helper.php
@@ -35,8 +35,8 @@ class Helper extends \OC\Share\Constants {
 	 * @throws \Exception
 	 * @return string Item target
 	 */
-	public static function generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
-		$suggestedTarget = null, $groupParent = null) {
+	public static function generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $suggestedTarget = null, $groupParent = null) {
+		// FIXME: $uidOwner and $groupParent seems to be unused
 		$backend = \OC\Share\Share::getBackend($itemType);
 		if ($shareType == self::SHARE_TYPE_LINK) {
 			if (isset($suggestedTarget)) {
@@ -54,91 +54,28 @@ class Helper extends \OC\Share\Constants {
 			if ($shareType == self::SHARE_TYPE_USER) {
 				// Share with is a user, so set share type to user and groups
 				$shareType = self::$shareTypeUserAndGroups;
-				$userAndGroups = array_merge(array($shareWith), \OC_Group::getUserGroups($shareWith));
-			} else {
-				$userAndGroups = false;
 			}
-			$exclude = null;
-			// Backend has 3 opportunities to generate a unique target
-			for ($i = 0; $i < 2; $i++) {
-				// Check if suggested target exists first
-				if ($i == 0 && isset($suggestedTarget)) {
-					$target = $suggestedTarget;
-				} else {
-					if ($shareType == self::SHARE_TYPE_GROUP) {
-						$target = $backend->generateTarget($itemSource, false, $exclude);
-					} else {
-						$target = $backend->generateTarget($itemSource, $shareWith, $exclude);
-					}
-					if (is_array($exclude) && in_array($target, $exclude)) {
-						break;
-					}
-				}
-				// Check if target already exists
-				$checkTarget = \OC\Share\Share::getItems($itemType, $target, $shareType, $shareWith);
-				if (!empty($checkTarget)) {
-					foreach ($checkTarget as $item) {
-						// Skip item if it is the group parent row
-						if (isset($groupParent) && $item['id'] == $groupParent) {
-							if (count($checkTarget) == 1) {
-								return $target;
-							} else {
-								continue;
-							}
-						}
-						if ($item['uid_owner'] == $uidOwner) {
-							if ($itemType == 'file' || $itemType == 'folder') {
-								$meta = \OC\Files\Filesystem::getFileInfo($itemSource);
-								if ($item['file_source'] == $meta['fileid']) {
-									return $target;
-								}
-							} else if ($item['item_source'] == $itemSource) {
-								return $target;
-							}
-						}
-					}
-					if (!isset($exclude)) {
-						$exclude = array();
-					}
-					// Find similar targets to improve backend's chances to generate a unqiue target
-					if ($userAndGroups) {
-						if ($column == 'file_target') {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share`'
-								.' WHERE `item_type` IN (\'file\', \'folder\')'
-								.' AND `share_type` IN (?,?,?)'
-								.' AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\')');
-							$result = $checkTargets->execute(array(self::SHARE_TYPE_USER, self::SHARE_TYPE_GROUP,
-								self::$shareTypeGroupUserUnique));
-						} else {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share`'
-								.' WHERE `item_type` = ? AND `share_type` IN (?,?,?)'
-								.' AND `share_with` IN (\''.implode('\',\'', $userAndGroups).'\')');
-							$result = $checkTargets->execute(array($itemType, self::SHARE_TYPE_USER,
-								self::SHARE_TYPE_GROUP, self::$shareTypeGroupUserUnique));
-						}
-					} else {
-						if ($column == 'file_target') {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share`'
-								.' WHERE `item_type` IN (\'file\', \'folder\')'
-								.' AND `share_type` = ? AND `share_with` = ?');
-							$result = $checkTargets->execute(array(self::SHARE_TYPE_GROUP, $shareWith));
-						} else {
-							$checkTargets = \OC_DB::prepare('SELECT `'.$column.'` FROM `*PREFIX*share`'
-								.' WHERE `item_type` = ? AND `share_type` = ? AND `share_with` = ?');
-							$result = $checkTargets->execute(array($itemType, self::SHARE_TYPE_GROUP, $shareWith));
-						}
-					}
-					while ($row = $result->fetchRow()) {
-						$exclude[] = $row[$column];
-					}
-				} else {
-					return $target;
+			$exclude = array();
+
+			$result = \OCP\Share::getItemsSharedWithUser($itemType, $shareWith);
+			foreach ($result as $row) {
+				if ($row['permissions'] > 0) {
+					$exclude[] = $row[$column];
 				}
 			}
+
+			// Check if suggested target exists first
+			if (!isset($suggestedTarget)) {
+				$suggestedTarget = $itemSource;
+			}
+			if ($shareType == self::SHARE_TYPE_GROUP) {
+				$target = $backend->generateTarget($suggestedTarget, false, $exclude);
+			} else {
+				$target = $backend->generateTarget($suggestedTarget, $shareWith, $exclude);
+			}
+
+			return $target;
 		}
-		$message = 'Sharing backend registered for '.$itemType.' did not generate a unique target for '.$itemSource;
-		\OC_Log::write('OCP\Share', $message, \OC_Log::ERROR);
-		throw new \Exception($message);
 	}
 
 	/**
@@ -146,10 +83,12 @@ class Helper extends \OC\Share\Constants {
 	 * @param int $parent Id of item to delete
 	 * @param bool $excludeParent If true, exclude the parent from the delete (optional)
 	 * @param string $uidOwner The user that the parent was shared with (optional)
+	 * @param int $newParent new parent for the childrens
 	 */
-	public static function delete($parent, $excludeParent = false, $uidOwner = null) {
+	public static function delete($parent, $excludeParent = false, $uidOwner = null, $newParent = null) {
 		$ids = array($parent);
 		$deletedItems = array();
+		$changeParent = array();
 		$parents = array($parent);
 		while (!empty($parents)) {
 			$parents = "'".implode("','", $parents)."'";
@@ -167,8 +106,6 @@ class Helper extends \OC\Share\Constants {
 			// Reset parents array, only go through loop again if items are found
 			$parents = array();
 			while ($item = $result->fetchRow()) {
-				$ids[] = $item['id'];
-				$parents[] = $item['id'];
 				$tmpItem = array(
 					'id' => $item['id'],
 					'shareWith' => $item['share_with'],
@@ -179,12 +116,28 @@ class Helper extends \OC\Share\Constants {
 				if (isset($item['file_target'])) {
 					$tmpItem['fileTarget'] = $item['file_target'];
 				}
-				$deletedItems[] = $tmpItem;
+				// if we have a new parent for the child we remember the child
+				// to update the parent, if not we add it to the list of items
+				// which should be deleted
+				if ($newParent !== null) {
+					$changeParent[] = $item['id'];
+				} else {
+					$deletedItems[] = $tmpItem;
+					$ids[] = $item['id'];
+					$parents[] = $item['id'];
+				}
 			}
 		}
 		if ($excludeParent) {
 			unset($ids[0]);
 		}
+
+		if (!empty($changeParent)) {
+			$idList = "'".implode("','", $changeParent)."'";
+			$query = \OC_DB::prepare('UPDATE `*PREFIX*share` SET `parent` = ? WHERE `id` IN ('.$idList.')');
+			$query->execute(array($newParent));
+		}
+
 		if (!empty($ids)) {
 			$idList = "'".implode("','", $ids)."'";
 			$query = \OC_DB::prepare('DELETE FROM `*PREFIX*share` WHERE `id` IN ('.$idList.')');
diff --git a/lib/private/share/hooks.php b/lib/private/share/hooks.php
index 9ac64d888ea..66b197b921b 100644
--- a/lib/private/share/hooks.php
+++ b/lib/private/share/hooks.php
@@ -45,6 +45,7 @@ class Hooks extends \OC\Share\Constants {
 	 * @param array $arguments
 	 */
 	public static function post_addToGroup($arguments) {
+
 		// Find the group shares and check if the user needs a unique target
 		$query = \OC_DB::prepare('SELECT * FROM `*PREFIX*share` WHERE `share_type` = ? AND `share_with` = ?');
 		$result = $query->execute(array(self::SHARE_TYPE_GROUP, $arguments['gid']));
@@ -52,18 +53,25 @@ class Hooks extends \OC\Share\Constants {
 			.' `item_target`, `parent`, `share_type`, `share_with`, `uid_owner`, `permissions`,'
 			.' `stime`, `file_source`, `file_target`) VALUES (?,?,?,?,?,?,?,?,?,?,?)');
 		while ($item = $result->fetchRow()) {
-			if ($item['item_type'] == 'file' || $item['item_type'] == 'file') {
-				$itemTarget = null;
-			} else {
-				$itemTarget = Helper::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER,
-						$arguments['uid'], $item['uid_owner'], $item['item_target'], $item['id']);
-			}
-			if (isset($item['file_source'])) {
-				$fileTarget = Helper::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER,
-					$arguments['uid'], $item['uid_owner'], $item['file_target'], $item['id']);
+
+			$sourceExists = \OC\Share\Share::getItemSharedWithBySource($item['item_type'], $item['item_source'], self::FORMAT_NONE, null, true, $arguments['uid']);
+
+			if ($sourceExists) {
+				$fileTarget = $sourceExists['file_target'];
+				$itemTarget = $sourceExists['item_target'];
 			} else {
-				$fileTarget = null;
+				$itemTarget = Helper::generateTarget($item['item_type'], $item['item_source'], self::SHARE_TYPE_USER, $arguments['uid'],
+					$item['owner'], null, $item['parent']);
+
+				// do we also need a file target
+				if ($item['item_type'] === 'file' || $item['item_type'] === 'folder') {
+					$fileTarget = Helper::generateTarget('file', $item['file_target'], self::SHARE_TYPE_USER, $arguments['uid'],
+							$item['owner'], null, $item['parent']);
+				} else {
+					$fileTarget = null;
+				}
 			}
+
 			// Insert an extra row for the group share if the item or file target is unique for this user
 			if ($itemTarget != $item['item_target'] || $fileTarget != $item['file_target']) {
 				$query->execute(array($item['item_type'], $item['item_source'], $itemTarget, $item['id'],
diff --git a/lib/private/share/share.php b/lib/private/share/share.php
index 22e354e515d..cfdc8aa9ffe 100644
--- a/lib/private/share/share.php
+++ b/lib/private/share/share.php
@@ -294,23 +294,32 @@ class Share extends \OC\Share\Constants {
 
 		$shares = array();
 
+		$column = ($itemType === 'file' || $itemType === 'folder') ? 'file_source' : 'item_source';
+
+		$where = ' `' . $column . '` = ? AND `item_type` = ? ';
+		$arguments = array($itemSource, $itemType);
+		// for link shares $user === null
+		if ($user !== null) {
+			$where .= ' AND `share_with` = ? ';
+			$arguments[] = $user;
+		}
+
 		// first check if there is a db entry for the specific user
 		$query = \OC_DB::prepare(
-				'SELECT `file_target`, `permissions`, `expiration`
+				'SELECT *
 					FROM
 					`*PREFIX*share`
-					WHERE
-					`item_source` = ? AND `item_type` = ? AND `share_with` = ?'
+					WHERE' . $where
 				);
 
-		$result = \OC_DB::executeAudited($query, array($itemSource, $itemType, $user));
+		$result = \OC_DB::executeAudited($query, $arguments);
 
 		while ($row = $result->fetchRow()) {
 			$shares[] = $row;
 		}
 
 		//if didn't found a result than let's look for a group share.
-		if(empty($shares)) {
+		if(empty($shares) && $user !== null) {
 			$groups = \OC_Group::getUserGroups($user);
 
 			$query = \OC_DB::prepare(
@@ -318,7 +327,7 @@ class Share extends \OC\Share\Constants {
 						FROM
 						`*PREFIX*share`
 						WHERE
-						`item_source` = ? AND `item_type` = ? AND `share_with` in (?)'
+						`' . $column . '` = ? AND `item_type` = ? AND `share_with` in (?)'
 					);
 
 			$result = \OC_DB::executeAudited($query, array($itemSource, $itemType, implode(',', $groups)));
@@ -339,11 +348,13 @@ class Share extends \OC\Share\Constants {
 	 * @param int $format (optional) Format type must be defined by the backend
 	 * @param mixed $parameters
 	 * @param boolean $includeCollections
-	 * @return mixed Return depends on format
+	 * @param string $shareWith (optional) define against which user should be checked, default: current user
+	 * @return array
 	 */
 	public static function getItemSharedWithBySource($itemType, $itemSource, $format = self::FORMAT_NONE,
-		$parameters = null, $includeCollections = false) {
-		return self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, \OC_User::getUser(), null, $format,
+		$parameters = null, $includeCollections = false, $shareWith = null) {
+		$shareWith = ($shareWith === null) ? \OC_User::getUser() : $shareWith;
+		return self::getItems($itemType, $itemSource, self::$shareTypeUserAndGroups, $shareWith, null, $format,
 			$parameters, 1, $includeCollections, true);
 	}
 
@@ -676,9 +687,31 @@ class Share extends \OC\Share\Constants {
 	 * @return boolean true on success or false on failure
 	 */
 	public static function unshare($itemType, $itemSource, $shareType, $shareWith) {
-		$item = self::getItems($itemType, $itemSource, $shareType, $shareWith, \OC_User::getUser(),self::FORMAT_NONE, null, 1);
-		if (!empty($item)) {
-			self::unshareItem($item);
+
+		// check if it is a valid itemType
+		self::getBackend($itemType);
+
+		$items = self::getItemSharedWithUser($itemType, $itemSource, $shareWith);
+
+		$toDelete = array();
+		$newParent = null;
+		$currentUser = \OC_User::getUser();
+		foreach ($items as $item) {
+			// delete the item with the expected share_type and owner
+			if ((int)$item['share_type'] === (int)$shareType && $item['uid_owner'] === $currentUser) {
+				$toDelete = $item;
+			// if there is more then one result we don't have to delete the children
+			// but update their parent. For group shares the new parent should always be
+			// the original group share and not the db entry with the unique name
+			} else if ((int)$item['share_type'] === self::$shareTypeGroupUserUnique) {
+				$newParent = $item['parent'];
+			} else {
+				$newParent = $item['id'];
+			}
+		}
+
+		if (!empty($toDelete)) {
+			self::unshareItem($toDelete, $newParent);
 			return true;
 		}
 		return false;
@@ -769,7 +802,7 @@ class Share extends \OC\Share\Constants {
 			}
 		}
 
-		if (!$itemUnshared && isset($groupShare)) {
+		if (!$itemUnshared && isset($groupShare) && !isset($uniqueGroupShare)) {
 			$query = \OC_DB::prepare('INSERT INTO `*PREFIX*share`'
 					.' (`item_type`, `item_source`, `item_target`, `parent`, `share_type`,'
 					.' `share_with`, `uid_owner`, `permissions`, `stime`, `file_source`, `file_target`)'
@@ -1050,9 +1083,10 @@ class Share extends \OC\Share\Constants {
 	/**
 	 * Unshares a share given a share data array
 	 * @param array $item Share data (usually database row)
+	 * @param int new parent ID
 	 * @return null
 	 */
-	protected static function unshareItem(array $item) {
+	protected static function unshareItem(array $item, $newParent = null) {
 		// Pass all the vars we have for now, they may be useful
 		$hookParams = array(
 			'id'            => $item['id'],
@@ -1069,7 +1103,7 @@ class Share extends \OC\Share\Constants {
 		}
 
 		\OC_Hook::emit('OCP\Share', 'pre_unshare', $hookParams);
-		$deletedShares = Helper::delete($item['id']);
+		$deletedShares = Helper::delete($item['id'], false, null, $newParent);
 		$deletedShares[] = $hookParams;
 		$hookParams['deletedShares'] = $deletedShares;
 		\OC_Hook::emit('OCP\Share', 'post_unshare', $hookParams);
@@ -1288,13 +1322,17 @@ class Share extends \OC\Share\Constants {
 				$queryArgs = array_merge($queryArgs, $collectionTypes);
 			}
 		}
+
+		if ($shareType == self::$shareTypeUserAndGroups && $limit === 1) {
+			// Make sure the unique user target is returned if it exists,
+			// unique targets should follow the group share in the database
+			// If the limit is not 1, the filtering can be done later
+			$where .= ' ORDER BY `*PREFIX*share`.`id` DESC';
+		} else {
+			$where .= ' ORDER BY `*PREFIX*share`.`id` ASC';
+		}
+
 		if ($limit != -1 && !$includeCollections) {
-			if ($shareType == self::$shareTypeUserAndGroups) {
-				// Make sure the unique user target is returned if it exists,
-				// unique targets should follow the group share in the database
-				// If the limit is not 1, the filtering can be done later
-				$where .= ' ORDER BY `*PREFIX*share`.`id` DESC';
-			}
 			// The limit must be at least 3, because filtering needs to be done
 			if ($limit < 3) {
 				$queryLimit = 3;
@@ -1303,7 +1341,6 @@ class Share extends \OC\Share\Constants {
 			}
 		} else {
 			$queryLimit = null;
-			$where .= ' ORDER BY `*PREFIX*share`.`id` ASC';
 		}
 		$select = self::createSelectStatement($format, $fileDependent, $uidOwner);
 		$root = strlen($root);
@@ -1311,7 +1348,7 @@ class Share extends \OC\Share\Constants {
 		$result = $query->execute($queryArgs);
 		if (\OC_DB::isError($result)) {
 			\OC_Log::write('OCP\Share',
-				\OC_DB::getErrorMessage($result) . ', select=' . $select . ' where=' . $where,
+				\OC_DB::getErrorMessage($result) . ', select=' . $select . ' where=',
 				\OC_Log::ERROR);
 		}
 		$items = array();
@@ -1325,6 +1362,12 @@ class Share extends \OC\Share\Constants {
 				$row['share_type'] = self::SHARE_TYPE_GROUP;
 				$row['unique_name'] = true; // remember that we use a unique name for this user
 				$row['share_with'] = $items[$row['parent']]['share_with'];
+				// if the group share was unshared from the user we keep the permission, otherwise
+				// we take the permission from the parent because this is always the up-to-date
+				// permission for the group share
+				if ($row['permissions'] > 0) {
+					$row['permissions'] = $items[$row['parent']]['permissions'];
+				}
 				// Remove the parent group share
 				unset($items[$row['parent']]);
 				if ($row['permissions'] == 0) {
@@ -1332,10 +1375,10 @@ class Share extends \OC\Share\Constants {
 				}
 			} else if (!isset($uidOwner)) {
 				// Check if the same target already exists
-				if (isset($targets[$row[$column]])) {
+				if (isset($targets[$row['id']])) {
 					// Check if the same owner shared with the user twice
 					// through a group and user share - this is allowed
-					$id = $targets[$row[$column]];
+					$id = $targets[$row['id']];
 					if (isset($items[$id]) && $items[$id]['uid_owner'] == $row['uid_owner']) {
 						// Switch to group share type to ensure resharing conditions aren't bypassed
 						if ($items[$id]['share_type'] != self::SHARE_TYPE_GROUP) {
@@ -1351,12 +1394,12 @@ class Share extends \OC\Share\Constants {
 							unset($items[$id]);
 							$id = $row['id'];
 						}
-						// Combine the permissions for the item
 						$items[$id]['permissions'] |= (int)$row['permissions'];
-						continue;
+
 					}
-				} else {
-					$targets[$row[$column]] = $row['id'];
+					continue;
+				} elseif (!empty($row['parent'])) {
+					$targets[$row['parent']] = $row['id'];
 				}
 			}
 			// Remove root from file source paths if retrieving own shared items
@@ -1394,6 +1437,7 @@ class Share extends \OC\Share\Constants {
 					}
 				}
 			}
+
 			if($checkExpireDate) {
 				if (self::expireItem($row)) {
 					continue;
@@ -1411,8 +1455,17 @@ class Share extends \OC\Share\Constants {
 				$row['displayname_owner'] = \OCP\User::getDisplayName($row['uid_owner']);
 			}
 
-			$items[$row['id']] = $row;
+			if ($row['permissions'] > 0) {
+				$items[$row['id']] = $row;
+			}
+
+		}
+
+		// group items if we are looking for items shared with the current user
+		if (isset($shareWith) && $shareWith === \OCP\User::getUser()) {
+			$items = self::groupItems($items, $itemType);
 		}
+
 		if (!empty($items)) {
 			$collectionItems = array();
 			foreach ($items as &$row) {
@@ -1498,6 +1551,47 @@ class Share extends \OC\Share\Constants {
 	}
 
 	/**
+	 * group items with link to the same source
+	 *
+	 * @param array $items
+	 * @param string $itemType
+	 * @return array of grouped items
+	 */
+	protected static function groupItems($items, $itemType) {
+
+		$fileSharing = ($itemType === 'file' || $itemType === 'folder') ? true : false;
+
+		$result = array();
+
+		foreach ($items as $item) {
+			$grouped = false;
+			foreach ($result as $key => $r) {
+				// for file/folder shares we need to compare file_source, otherwise we compare item_source
+				// only group shares if they already point to the same target, otherwise the file where shared
+				// before grouping of shares was added. In this case we don't group them toi avoid confusions
+				if (( $fileSharing && $item['file_source'] === $r['file_source'] && $item['file_target'] === $r['file_target']) ||
+						(!$fileSharing && $item['item_source'] === $r['item_source'] && $item['item_target'] === $r['item_target'])) {
+					// add the first item to the list of grouped shares
+					if (!isset($result[$key]['grouped'])) {
+						$result[$key]['grouped'][] = $result[$key];
+					}
+					$result[$key]['permissions'] = (int) $item['permissions'] | (int) $r['permissions'];
+					$result[$key]['grouped'][] = $item;
+					$grouped = true;
+					break;
+				}
+			}
+
+			if (!$grouped) {
+				$result[] = $item;
+			}
+
+		}
+
+		return $result;
+	}
+
+/**
 	 * Put shared item into the database
 	 * @param string $itemType Item type
 	 * @param string $itemSource Item source
@@ -1514,121 +1608,34 @@ class Share extends \OC\Share\Constants {
 	 */
 	private static function put($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
 		$permissions, $parentFolder = null, $token = null, $itemSourceName = null, \DateTime $expirationDate = null) {
-		$backend = self::getBackend($itemType);
-		$l = \OC_L10N::get('lib');
-		// Check if this is a reshare
-		if ($checkReshare = self::getItemSharedWithBySource($itemType, $itemSource, self::FORMAT_NONE, null, true)) {
 
-			// Check if attempting to share back to owner
-			if ($checkReshare['uid_owner'] == $shareWith && $shareType == self::SHARE_TYPE_USER) {
-				$message = 'Sharing %s failed, because the user %s is the original sharer';
-				$message_t = $l->t('Sharing %s failed, because the user %s is the original sharer', array($itemSourceName, $shareWith));
+		$queriesToExecute = array();
+		$suggestedItemTarget = null;
 
-				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OC_Log::ERROR);
-				throw new \Exception($message_t);
-			}
-			// Check if share permissions is granted
-			if (self::isResharingAllowed() && (int)$checkReshare['permissions'] & \OCP\PERMISSION_SHARE) {
-				if (~(int)$checkReshare['permissions'] & $permissions) {
-					$message = 'Sharing %s failed, because the permissions exceed permissions granted to %s';
-					$message_t = $l->t('Sharing %s failed, because the permissions exceed permissions granted to %s', array($itemSourceName, $uidOwner));
-
-					\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $uidOwner), \OC_Log::ERROR);
-					throw new \Exception($message_t);
-				} else {
-					// TODO Don't check if inside folder
-					$parent = $checkReshare['id'];
-					$itemSource = $checkReshare['item_source'];
-					$fileSource = $checkReshare['file_source'];
-					$suggestedItemTarget = $checkReshare['item_target'];
-					$suggestedFileTarget = $checkReshare['file_target'];
-					$filePath = $checkReshare['file_target'];
-					$expirationDate = min($expirationDate, $checkReshare['expiration']);
-				}
-			} else {
-				$message = 'Sharing %s failed, because resharing is not allowed';
-				$message_t = $l->t('Sharing %s failed, because resharing is not allowed', array($itemSourceName));
-
-				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName), \OC_Log::ERROR);
-				throw new \Exception($message_t);
-			}
-		} else {
-			$parent = null;
-			$suggestedItemTarget = null;
-			$suggestedFileTarget = null;
-			if (!$backend->isValidSource($itemSource, $uidOwner)) {
-				$message = 'Sharing %s failed, because the sharing backend for '
-					.'%s could not find its source';
-				$message_t = $l->t('Sharing %s failed, because the sharing backend for %s could not find its source', array($itemSource, $itemType));
-				\OC_Log::write('OCP\Share', sprintf($message, $itemSource, $itemType), \OC_Log::ERROR);
-				throw new \Exception($message_t);
-			}
-			if ($backend instanceof \OCP\Share_Backend_File_Dependent) {
-				$filePath = $backend->getFilePath($itemSource, $uidOwner);
-				if ($itemType == 'file' || $itemType == 'folder') {
-					$fileSource = $itemSource;
-				} else {
-					$meta = \OC\Files\Filesystem::getFileInfo($filePath);
-					$fileSource = $meta['fileid'];
-				}
-				if ($fileSource == -1) {
-					$message = 'Sharing %s failed, because the file could not be found in the file cache';
-					$message_t = $l->t('Sharing %s failed, because the file could not be found in the file cache', array($itemSource));
-
-					\OC_Log::write('OCP\Share', sprintf($message, $itemSource), \OC_Log::ERROR);
-					throw new \Exception($message_t);
-				}
-			} else {
-				$filePath = null;
-				$fileSource = null;
-			}
+		$result = self::checkReshare($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $itemSourceName, $expirationDate);
+		if(!empty($result)) {
+			$parent = $result['parent'];
+			$itemSource = $result['itemSource'];
+			$fileSource = $result['fileSource'];
+			$suggestedItemTarget = $result['suggestedItemTarget'];
+			$suggestedFileTarget = $result['suggestedFileTarget'];
+			$filePath = $result['filePath'];
+			$expirationDate = $result['expirationDate'];
 		}
 
-		// Share with a group
+		$isGroupShare = false;
 		if ($shareType == self::SHARE_TYPE_GROUP) {
-			$groupItemTarget = Helper::generateTarget($itemType, $itemSource, $shareType, $shareWith['group'],
-				$uidOwner, $suggestedItemTarget);
-			$run = true;
-			$error = '';
-			\OC_Hook::emit('OCP\Share', 'pre_shared', array(
-				'itemType' => $itemType,
-				'itemSource' => $itemSource,
-				'itemTarget' => $groupItemTarget,
-				'shareType' => $shareType,
-				'shareWith' => $shareWith['group'],
-				'uidOwner' => $uidOwner,
-				'permissions' => $permissions,
-				'fileSource' => $fileSource,
-				'expiration' => $expirationDate,
-				'token' => $token,
-				'run' => &$run,
-				'error' => &$error
-			));
-
-			if ($run === false) {
-				throw new \Exception($error);
-			}
-
-			if (isset($fileSource)) {
-				if ($parentFolder) {
-					if ($parentFolder === true) {
-						$groupFileTarget = Helper::generateTarget('file', $filePath, $shareType,
-							$shareWith['group'], $uidOwner, $suggestedFileTarget);
-						// Set group default file target for future use
-						$parentFolders[0]['folder'] = $groupFileTarget;
-					} else {
-						// Get group default file target
-						$groupFileTarget = $parentFolder[0]['folder'].$itemSource;
-						$parent = $parentFolder[0]['id'];
-					}
-				} else {
-					$groupFileTarget = Helper::generateTarget('file', $filePath, $shareType, $shareWith['group'],
-						$uidOwner, $suggestedFileTarget);
-				}
-			} else {
-				$groupFileTarget = null;
+			$isGroupShare = true;
+			$users = \OC_Group::usersInGroup($shareWith['group']);
+			// remove current user from list
+			if (in_array(\OCP\User::getUser(), $users)) {
+				unset($users[array_search(\OCP\User::getUser(), $users)]);
 			}
-			$queriesToExecute = array();
+			$groupItemTarget = Helper::generateTarget($itemType, $itemSource, $shareType, $shareWith['group'],
+					$uidOwner, $suggestedItemTarget);
+			$groupFileTarget = $filePath;
+
+			// add group share to table and remember the id as parent
 			$queriesToExecute['groupShare'] = array(
 				'itemType'			=> $itemType,
 				'itemSource'		=> $itemSource,
@@ -1639,165 +1646,229 @@ class Share extends \OC\Share\Constants {
 				'permissions'		=> $permissions,
 				'shareTime'			=> time(),
 				'fileSource'		=> $fileSource,
-				'fileTarget'		=> $groupFileTarget,
+				'fileTarget'		=> $filePath,
 				'token'				=> $token,
 				'parent'			=> $parent,
 				'expiration'		=> $expirationDate,
 			);
-			// Loop through all users of this group in case we need to add an extra row
-			foreach ($shareWith['users'] as $uid) {
-				$itemTarget = Helper::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $uid,
+
+		} else {
+			$users = array($shareWith);
+			$itemTarget = Helper::generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
+					$suggestedItemTarget);
+		}
+
+		$run = true;
+		$error = '';
+		$preHookData = array(
+			'itemType' => $itemType,
+			'itemSource' => $itemSource,
+			'shareType' => $shareType,
+			'uidOwner' => $uidOwner,
+			'permissions' => $permissions,
+			'fileSource' => $fileSource,
+			'expiration' => $expirationDate,
+			'token' => $token,
+			'run' => &$run,
+			'error' => &$error
+		);
+
+		$preHookData['itemTarget'] = ($isGroupShare) ? $groupItemTarget : $itemTarget;
+		$preHookData['shareWith'] = ($isGroupShare) ? $shareWith['group'] : $shareWith;
+
+		\OC_Hook::emit('OCP\Share', 'pre_shared', $preHookData);
+
+		if ($run === false) {
+			throw new \Exception($error);
+		}
+
+		foreach ($users as $user) {
+			$sourceId = ($itemType === 'file' || $itemType === 'folder') ? $fileSource : $itemSource;
+			$sourceExists = self::getItemSharedWithBySource($itemType, $sourceId, self::FORMAT_NONE, null, true, $user);
+
+			$shareType = ($isGroupShare) ? self::$shareTypeGroupUserUnique : $shareType;
+
+			if ($sourceExists) {
+				$fileTarget = $sourceExists['file_target'];
+				$itemTarget = $sourceExists['item_target'];
+
+				// for group shares we don't need a additional entry if the target is the same
+				if($isGroupShare && $groupItemTarget === $itemTarget) {
+					continue;
+				}
+
+			} elseif(!$sourceExists && !$isGroupShare)  {
+
+				$itemTarget = Helper::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $user,
 					$uidOwner, $suggestedItemTarget, $parent);
 				if (isset($fileSource)) {
 					if ($parentFolder) {
 						if ($parentFolder === true) {
-							$fileTarget = Helper::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $uid,
+							$fileTarget = Helper::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $user,
 								$uidOwner, $suggestedFileTarget, $parent);
 							if ($fileTarget != $groupFileTarget) {
-								$parentFolders[$uid]['folder'] = $fileTarget;
+								$parentFolders[$user]['folder'] = $fileTarget;
 							}
-						} else if (isset($parentFolder[$uid])) {
-							$fileTarget = $parentFolder[$uid]['folder'].$itemSource;
-							$parent = $parentFolder[$uid]['id'];
+						} else if (isset($parentFolder[$user])) {
+							$fileTarget = $parentFolder[$user]['folder'].$itemSource;
+							$parent = $parentFolder[$user]['id'];
 						}
 					} else {
 						$fileTarget = Helper::generateTarget('file', $filePath, self::SHARE_TYPE_USER,
-							$uid, $uidOwner, $suggestedFileTarget, $parent);
+							$user, $uidOwner, $suggestedFileTarget, $parent);
 					}
 				} else {
 					$fileTarget = null;
 				}
-				// Insert an extra row for the group share if the item or file target is unique for this user
-				if ($itemTarget != $groupItemTarget || (isset($fileSource) && $fileTarget != $groupFileTarget)) {
-					$queriesToExecute[] = array(
-						'itemType'			=> $itemType,
-						'itemSource'		=> $itemSource,
-						'itemTarget'		=> $itemTarget,
-						'shareType'			=> self::$shareTypeGroupUserUnique,
-						'shareWith'			=> $uid,
-						'uidOwner'			=> $uidOwner,
-						'permissions'		=> $permissions,
-						'shareTime'			=> time(),
-						'fileSource'		=> $fileSource,
-						'fileTarget'		=> $fileTarget,
-						'token'				=> $token,
-						//'parent'			=> $parent,
-						'expiration'		=> $expirationDate,
-					);
+
+			} else {
+
+				// group share which doesn't exists until now, check if we need a unique target for this user
+
+				$itemTarget = Helper::generateTarget($itemType, $itemSource, self::SHARE_TYPE_USER, $user,
+					$uidOwner, $suggestedItemTarget, $parent);
+
+				// do we also need a file target
+				if (isset($fileSource)) {
+					$fileTarget = Helper::generateTarget('file', $filePath, self::SHARE_TYPE_USER, $user,
+							$uidOwner, $suggestedFileTarget, $parent);
+				} else {
+					$fileTarget = null;
+				}
+
+				if ($itemTarget === $groupItemTarget && (isset($fileSource) && $fileTarget === $groupItemTarget)) {
+					continue;
 				}
 			}
 
+			$queriesToExecute[] = array(
+					'itemType'			=> $itemType,
+					'itemSource'		=> $itemSource,
+					'itemTarget'		=> $itemTarget,
+					'shareType'			=> $shareType,
+					'shareWith'			=> $user,
+					'uidOwner'			=> $uidOwner,
+					'permissions'		=> $permissions,
+					'shareTime'			=> time(),
+					'fileSource'		=> $fileSource,
+					'fileTarget'		=> $fileTarget,
+					'token'				=> $token,
+					'parent'			=> $parent,
+					'expiration'		=> $expirationDate,
+				);
+
+		}
+
+		if ($isGroupShare) {
 			self::insertShare($queriesToExecute['groupShare']);
 			// Save this id, any extra rows for this group share will need to reference it
 			$parent = \OC_DB::insertid('*PREFIX*share');
 			unset($queriesToExecute['groupShare']);
+		}
 
-			foreach ($queriesToExecute as $shareQuery) {
-				$shareQuery['parent'] = $parent;
-				self::insertShare($shareQuery);
-			}
+		foreach ($queriesToExecute as $shareQuery) {
+			$shareQuery['parent'] = $parent;
+			self::insertShare($shareQuery);
+		}
 
-			\OC_Hook::emit('OCP\Share', 'post_shared', array(
-				'itemType' => $itemType,
-				'itemSource' => $itemSource,
-				'itemTarget' => $groupItemTarget,
-				'parent' => $parent,
-				'shareType' => $shareType,
-				'shareWith' => $shareWith['group'],
-				'uidOwner' => $uidOwner,
-				'permissions' => $permissions,
-				'fileSource' => $fileSource,
-				'fileTarget' => $groupFileTarget,
-				'id' => $parent,
-				'token' => $token,
-				'expirationDate' => $expirationDate,
-			));
-
-			if ($parentFolder === true) {
-				// Return parent folders to preserve file target paths for potential children
-				return $parentFolders;
+		$postHookData = array(
+			'itemType' => $itemType,
+			'itemSource' => $itemSource,
+			'parent' => $parent,
+			'shareType' => $shareType,
+			'uidOwner' => $uidOwner,
+			'permissions' => $permissions,
+			'fileSource' => $fileSource,
+			'id' => $parent,
+			'token' => $token,
+			'expirationDate' => $expirationDate,
+		);
+
+		$postHookData['shareWith'] = ($isGroupShare) ? $shareWith['group'] : $shareWith;
+		$postHookData['itemTarget'] = ($isGroupShare) ? $groupItemTarget : $itemTarget;
+		$postHookData['fileTarget'] = ($isGroupShare) ? $groupFileTarget : $fileTarget;
+
+		\OC_Hook::emit('OCP\Share', 'post_shared', $postHookData);
+
+
+		return true;
+	}
+
+	private static function checkReshare($itemType, $itemSource, $shareType, $shareWith, $uidOwner, $permissions, $itemSourceName, $expirationDate) {
+		$backend = self::getBackend($itemType);
+		$l = \OC_L10N::get('lib');
+
+		$checkReshare = self::getItemSharedWithBySource($itemType, $itemSource, self::FORMAT_NONE, null, true);
+		if ($checkReshare) {
+			// Check if attempting to share back to owner
+			if ($checkReshare['uid_owner'] == $shareWith && $shareType == self::SHARE_TYPE_USER) {
+				$message = 'Sharing %s failed, because the user %s is the original sharer';
+				$message_t = $l->t('Sharing %s failed, because the user %s is the original sharer', array($itemSourceName, $shareWith));
+
+				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $shareWith), \OC_Log::ERROR);
+				throw new \Exception($message_t);
 			}
-		} else {
-			$itemTarget = Helper::generateTarget($itemType, $itemSource, $shareType, $shareWith, $uidOwner,
-				$suggestedItemTarget);
-			$run = true;
-			$error = '';
-			\OC_Hook::emit('OCP\Share', 'pre_shared', array(
-				'itemType' => $itemType,
-				'itemSource' => $itemSource,
-				'itemTarget' => $itemTarget,
-				'shareType' => $shareType,
-				'shareWith' => $shareWith,
-				'uidOwner' => $uidOwner,
-				'permissions' => $permissions,
-				'fileSource' => $fileSource,
-				'token' => $token,
-				'expirationDate' => $expirationDate,
-				'run' => &$run,
-				'error' => &$error,
-			));
-
-			if ($run === false) {
-				throw new \Exception($error);
-			}
-
-			if (isset($fileSource)) {
-				if ($parentFolder) {
-					if ($parentFolder === true) {
-						$fileTarget = Helper::generateTarget('file', $filePath, $shareType, $shareWith,
-							$uidOwner, $suggestedFileTarget);
-						$parentFolders['folder'] = $fileTarget;
-					} else {
-						$fileTarget = $parentFolder['folder'].$itemSource;
-						$parent = $parentFolder['id'];
-					}
+
+			// Check if share permissions is granted
+			if (self::isResharingAllowed() && (int)$checkReshare['permissions'] & \OCP\PERMISSION_SHARE) {
+				if (~(int)$checkReshare['permissions'] & $permissions) {
+					$message = 'Sharing %s failed, because the permissions exceed permissions granted to %s';
+					$message_t = $l->t('Sharing %s failed, because the permissions exceed permissions granted to %s', array($itemSourceName, $uidOwner));
+
+					\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName, $uidOwner), \OC_Log::ERROR);
+					throw new \Exception($message_t);
 				} else {
-					$fileTarget = Helper::generateTarget('file', $filePath, $shareType, $shareWith, $uidOwner,
-						$suggestedFileTarget);
+					// TODO Don't check if inside folder
+					$result['parent'] = $checkReshare['id'];
+					$result['itemSource'] = $checkReshare['item_source'];
+					$result['fileSource'] = $checkReshare['file_source'];
+					$result['suggestedItemTarget'] = $checkReshare['item_target'];
+					$result['suggestedFileTarget'] = $checkReshare['file_target'];
+					$result['filePath'] = $checkReshare['file_target'];
+					$result['expirationDate'] = min($expirationDate, $checkReshare['expiration']);
 				}
 			} else {
-				$fileTarget = null;
-			}
+				$message = 'Sharing %s failed, because resharing is not allowed';
+				$message_t = $l->t('Sharing %s failed, because resharing is not allowed', array($itemSourceName));
 
-			self::insertShare(array(
-				'itemType'			=> $itemType,
-				'itemSource'		=> $itemSource,
-				'itemTarget'		=> $itemTarget,
-				'shareType'			=> $shareType,
-				'shareWith'			=> $shareWith,
-				'uidOwner'			=> $uidOwner,
-				'permissions'		=> $permissions,
-				'shareTime'			=> time(),
-				'fileSource'		=> $fileSource,
-				'fileTarget'		=> $fileTarget,
-				'token'				=> $token,
-				'parent'			=> $parent,
-				'expiration'		=> $expirationDate,
-			));
+				\OC_Log::write('OCP\Share', sprintf($message, $itemSourceName), \OC_Log::ERROR);
+				throw new \Exception($message_t);
+			}
+		} else {
+			$result['parent'] = null;
+			$result['suggestedItemTarget'] = null;
+			$result['suggestedFileTarget'] = null;
+			$result['itemSource'] = $itemSource;
+			$result['expirationDate'] = $expirationDate;
+			if (!$backend->isValidSource($itemSource, $uidOwner)) {
+				$message = 'Sharing %s failed, because the sharing backend for '
+					.'%s could not find its source';
+				$message_t = $l->t('Sharing %s failed, because the sharing backend for %s could not find its source', array($itemSource, $itemType));
+				\OC_Log::write('OCP\Share', sprintf($message, $itemSource, $itemType), \OC_Log::ERROR);
+				throw new \Exception($message_t);
+			}
+			if ($backend instanceof \OCP\Share_Backend_File_Dependent) {
+				$result['filePath'] = $backend->getFilePath($itemSource, $uidOwner);
+				if ($itemType == 'file' || $itemType == 'folder') {
+					$result['fileSource'] = $itemSource;
+				} else {
+					$meta = \OC\Files\Filesystem::getFileInfo($result['filePath']);
+					$result['fileSource'] = $meta['fileid'];
+				}
+				if ($result['fileSource'] == -1) {
+					$message = 'Sharing %s failed, because the file could not be found in the file cache';
+					$message_t = $l->t('Sharing %s failed, because the file could not be found in the file cache', array($itemSource));
 
-			$id = \OC_DB::insertid('*PREFIX*share');
-			\OC_Hook::emit('OCP\Share', 'post_shared', array(
-				'itemType' => $itemType,
-				'itemSource' => $itemSource,
-				'itemTarget' => $itemTarget,
-				'parent' => $parent,
-				'shareType' => $shareType,
-				'shareWith' => $shareWith,
-				'uidOwner' => $uidOwner,
-				'permissions' => $permissions,
-				'fileSource' => $fileSource,
-				'fileTarget' => $fileTarget,
-				'id' => $id,
-				'token' => $token,
-				'expirationDate' => $expirationDate,
-			));
-			if ($parentFolder === true) {
-				$parentFolders['id'] = $id;
-				// Return parent folder to preserve file target paths for potential children
-				return $parentFolders;
+					\OC_Log::write('OCP\Share', sprintf($message, $itemSource), \OC_Log::ERROR);
+					throw new \Exception($message_t);
+				}
+			} else {
+				$result['filePath'] = null;
+				$result['fileSource'] = null;
 			}
 		}
-		return true;
+
+		return $result;
 	}
 
 	private static function insertShare(array $shareData)
@@ -1873,9 +1944,9 @@ class Share extends \OC\Share\Constants {
 		$select = '*';
 		if ($format == self::FORMAT_STATUSES) {
 			if ($fileDependent) {
-				$select = '`*PREFIX*share`.`id`, `*PREFIX*share`.`parent`, `share_type`, `path`, `storage`, `share_with`, `uid_owner` , `file_source`, `stime`';
+				$select = '`*PREFIX*share`.`id`, `*PREFIX*share`.`parent`, `share_type`, `path`, `storage`, `share_with`, `uid_owner` , `file_source`, `stime`, `*PREFIX*share`.`permissions`';
 			} else {
-				$select = '`id`, `parent`, `share_type`, `share_with`, `uid_owner`, `item_source`, `stime`';
+				$select = '`id`, `parent`, `share_type`, `share_with`, `uid_owner`, `item_source`, `stime`, `*PREFIX*share`.`permissions`';
 			}
 		} else {
 			if (isset($uidOwner)) {
diff --git a/lib/public/share.php b/lib/public/share.php
index bb9c6ec5886..8ce389a1ed7 100644
--- a/lib/public/share.php
+++ b/lib/public/share.php
@@ -139,7 +139,7 @@ class Share extends \OC\Share\Constants {
 	 * @param int $format (optional) Format type must be defined by the backend
 	 * @param mixed $parameters
 	 * @param bool $includeCollections
-	 * @return mixed Return depends on format
+	 * @return array
 	 */
 	public static function getItemSharedWithBySource($itemType, $itemSource, $format = self::FORMAT_NONE,
 		$parameters = null, $includeCollections = false) {
@@ -361,7 +361,7 @@ interface Share_Backend {
 	 * Get a unique name of the item for the specified user
 	 * @param string $itemSource
 	 * @param string|false $shareWith User the item is being shared with
-	 * @param array|null $exclude List of similar item names already existing as shared items
+	 * @param array|null $exclude List of similar item names already existing as shared items @deprecated since version OC7
 	 * @return string Target name
 	 *
 	 * This function needs to verify that the user does not already have an item with this name.
diff --git a/tests/lib/share/backend.php b/tests/lib/share/backend.php
index 420bd9d88b3..50ce24e07b6 100644
--- a/tests/lib/share/backend.php
+++ b/tests/lib/share/backend.php
@@ -38,19 +38,36 @@ class Test_Share_Backend implements OCP\Share_Backend {
 
 	public function generateTarget($itemSource, $shareWith, $exclude = null) {
 		// Always make target be test.txt to cause conflicts
-		$target = 'test.txt';
-		if (isset($exclude)) {
+
+		if (substr($itemSource, 0, strlen('test')) !== 'test') {
+			$target = "test.txt";
+		} else {
+			$target = $itemSource;
+		}
+
+
+		$shares = \OCP\Share::getItemsSharedWithUser('test', $shareWith);
+
+		$knownTargets = array();
+		foreach ($shares as $share) {
+			$knownTargets[] = $share['item_target'];
+		}
+
+
+		if (in_array($target, $knownTargets)) {
 			$pos = strrpos($target, '.');
 			$name = substr($target, 0, $pos);
 			$ext = substr($target, $pos);
 			$append = '';
 			$i = 1;
-			while (in_array($name.$append.$ext, $exclude)) {
+			while (in_array($name.$append.$ext, $knownTargets)) {
 				$append = $i;
 				$i++;
 			}
 			$target = $name.$append.$ext;
+
 		}
+
 		return $target;
 	}
 
diff --git a/tests/lib/share/share.php b/tests/lib/share/share.php
index bb827eece73..fbff89567d2 100644
--- a/tests/lib/share/share.php
+++ b/tests/lib/share/share.php
@@ -48,8 +48,8 @@ class Test_Share extends PHPUnit_Framework_TestCase {
 		OC_User::setUserId($this->user1);
 		OC_Group::clearBackends();
 		OC_Group::useBackend(new OC_Group_Dummy);
-		$this->group1 = uniqid('group_');
-		$this->group2 = uniqid('group_');
+		$this->group1 = uniqid('group1_');
+		$this->group2 = uniqid('group2_');
 		OC_Group::createGroup($this->group1);
 		OC_Group::createGroup($this->group2);
 		OC_Group::addToGroup($this->user1, $this->group1);
@@ -522,7 +522,7 @@ class Test_Share extends PHPUnit_Framework_TestCase {
 		OC_User::setUserId($this->user2);
 		$this->assertEquals(array(OCP\PERMISSION_READ | OCP\PERMISSION_UPDATE), OCP\Share::getItemSharedWith('test', 'test.txt', Test_Share_Backend::FORMAT_PERMISSIONS));
 		OC_User::setUserId($this->user4);
-		$this->assertEquals(array(), OCP\Share::getItemsSharedWith('test', Test_Share_Backend::FORMAT_TARGET));
+		$this->assertEquals(array('test.txt'), OCP\Share::getItemsSharedWith('test', Test_Share_Backend::FORMAT_TARGET));
 
 		// Valid share with same person - group then user
 		OC_User::setUserId($this->user1);
@@ -733,20 +733,88 @@ class Test_Share extends PHPUnit_Framework_TestCase {
 			array(false, array('share_with' => '1234567890', 'share_type' => '3', 'id' => 101)),
 			array(false, array('share_with' => '1234567890', 'share_type' => 3, 'id' => 101)),
 		);
+	}
 
-		/*
-		if (!isset($linkItem['share_with'])) {
-			return true;
-		}
+	/**
+	 * @dataProvider dataProviderTestGroupItems
+	 * @param type $ungrouped
+	 * @param type $grouped
+	 */
+	function testGroupItems($ungrouped, $grouped) {
 
-		if ($linkItem['share_type'] != \OCP\Share::SHARE_TYPE_LINK) {
-			return true;
-		}
+		$result = DummyShareClass::groupItemsTest($ungrouped);
 
-		if ( \OC::$session->exists('public_link_authenticated')
-			&& \OC::$session->get('public_link_authenticated') === $linkItem['id'] ) {
-			return true;
+		$this->compareArrays($grouped, $result);
+
+	}
+
+	function compareArrays($result, $expectedResult) {
+		foreach ($expectedResult as $key => $value) {
+			if (is_array($value)) {
+				$this->compareArrays($result[$key], $value);
+			} else {
+				$this->assertSame($value, $result[$key]);
+			}
 		}
-		 * */
+	}
+
+	function dataProviderTestGroupItems() {
+		return array(
+			// one array with one share
+			array(
+				array( // input
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_ALL, 'item_target' => 't1')),
+				array( // expected result
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_ALL, 'item_target' => 't1'))),
+			// two shares both point to the same source
+			array(
+				array( // input
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ, 'item_target' => 't1'),
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_UPDATE, 'item_target' => 't1'),
+					),
+				array( // expected result
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ | \OCP\PERMISSION_UPDATE, 'item_target' => 't1',
+						'grouped' => array(
+							array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ, 'item_target' => 't1'),
+							array('item_source' => 1, 'permissions' => \OCP\PERMISSION_UPDATE, 'item_target' => 't1'),
+							)
+						),
+					)
+				),
+			// two shares both point to the same source but with different targets
+			array(
+				array( // input
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ, 'item_target' => 't1'),
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_UPDATE, 'item_target' => 't2'),
+					),
+				array( // expected result
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ, 'item_target' => 't1'),
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_UPDATE, 'item_target' => 't2'),
+					)
+				),
+			// three shares two point to the same source
+			array(
+				array( // input
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ, 'item_target' => 't1'),
+					array('item_source' => 2, 'permissions' => \OCP\PERMISSION_CREATE, 'item_target' => 't2'),
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_UPDATE, 'item_target' => 't1'),
+					),
+				array( // expected result
+					array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ | \OCP\PERMISSION_UPDATE, 'item_target' => 't1',
+						'grouped' => array(
+							array('item_source' => 1, 'permissions' => \OCP\PERMISSION_READ, 'item_target' => 't1'),
+							array('item_source' => 1, 'permissions' => \OCP\PERMISSION_UPDATE, 'item_target' => 't1'),
+							)
+						),
+					array('item_source' => 2, 'permissions' => \OCP\PERMISSION_CREATE, 'item_target' => 't2'),
+					)
+				),
+		);
+	}
+}
+
+class DummyShareClass extends \OC\Share\Share {
+	public static function groupItemsTest($items) {
+		return parent::groupItems($items, 'test');
 	}
 }