[stable16] Fix "unshare group share from self" activity

lib/AppInfo/Application.php

@@ -110,6 +110,6 @@ public function registerFilesActivity() {
 
 		$eventDispatcher = $this->getContainer()->getServer()->getEventDispatcher();
 		$eventDispatcher->addListener('OCP\Share::preUnshare', [FilesHooksStatic::class, 'unShare']);
-		$eventDispatcher->addListener('OCP\Share::postUnshareFromSelf', [FilesHooksStatic::class, 'unShare']);
+		$eventDispatcher->addListener('OCP\Share::postUnshareFromSelf', [FilesHooksStatic::class, 'unShareSelf']);
 	}
 }

lib/FilesHooks.php

@@ -781,6 +781,21 @@ public function unShare(IShare $share) {
 		}
 	}
 
+	/**
+	 * Manage unsharing a share from self only events
+	 * @param IShare $share
+	 * @throws \OCP\Files\NotFoundException
+	 */
+	public function unShareSelf(IShare $share) {
+		if (in_array($share->getNodeType(), ['file', 'folder'], true)) {
+			if ($share->getShareType() === Share::SHARE_TYPE_GROUP) {
+				$this->unshareFromSelfGroup($share);
+			} else {
+				$this->unShare($share);
+			}
+		}
+	}
+
 	/**
 	 * Unharing a file or folder from a user
 	 *
@@ -854,6 +869,22 @@ protected function unshareFromGroup(IShare $share) {
 		}
 	}
 
+	/**
+	 * Unsharing a file or folder from self from a group share
+	 *
+	 * @param IShare $share
+	 * @throws \OCP\Files\NotFoundException
+	 */
+	protected function unshareFromSelfGroup(IShare $share) {
+		// User performing the unshare
+		$this->shareNotificationForSharer('self_unshared', $this->currentUser->getUID(), $share->getNodeId(), $share->getNodeType());
+
+		// Owner
+		if ($this->currentUser->getUID() !== null) {
+			$this->shareNotificationForOriginalOwners($this->currentUser->getUID(), 'self_unshared_by', $this->currentUser->getUID(), $share->getNodeId(), $share->getNodeType());
+		}
+	}
+
 	/**
 	 * Sharing a file or folder via link/public
 	 *

lib/FilesHooksStatic.php

@@ -105,4 +105,15 @@ public static function unShare(GenericEvent $event) {
 			self::getHooks()->unShare($share);
 		}
 	}
+
+	/**
+	 * "Unsharing a share from self only" event
+	 * @param GenericEvent $event
+	 */
+	public static function unShareSelf(GenericEvent $event) {
+		$share = $event->getSubject();
+		if ($share instanceof IShare) {
+			self::getHooks()->unShareSelf($share);
+		}
+	}
 }