From 5251db72245657cad3ea1aae15b2c1d408e470de Mon Sep 17 00:00:00 2001
From: Taloth Saldono <Taloth@users.noreply.github.com>
Date: Sat, 16 May 2020 19:08:55 +0200
Subject: [PATCH] Fixed recursion issue when emptying recycle bin

---
 .../DiskTests/DiskProviderFixtureBase.cs      | 32 +++++++++++++++++++
 src/NzbDrone.Common/Disk/DiskProviderBase.cs  | 21 ++++++++----
 .../MediaFiles/DiskScanService.cs             |  8 ++---
 3 files changed, 49 insertions(+), 12 deletions(-)

diff --git a/src/NzbDrone.Common.Test/DiskTests/DiskProviderFixtureBase.cs b/src/NzbDrone.Common.Test/DiskTests/DiskProviderFixtureBase.cs
index c81aefbd8..77f048f33 100644
--- a/src/NzbDrone.Common.Test/DiskTests/DiskProviderFixtureBase.cs
+++ b/src/NzbDrone.Common.Test/DiskTests/DiskProviderFixtureBase.cs
@@ -212,6 +212,38 @@ namespace NzbDrone.Common.Test.DiskTests
             Subject.GetParentFolder(path).Should().Be(parent);
         }
 
+        [Test]
+        public void RemoveEmptySubfolders_should_remove_nested_empty_folder()
+        {
+            var mainDir = GetTempFilePath();
+            var subDir1 = Path.Combine(mainDir, "depth1");
+            var subDir2 = Path.Combine(subDir1, "depth2");
+            Directory.CreateDirectory(subDir2);
+
+            Subject.RemoveEmptySubfolders(mainDir);
+
+            Directory.Exists(mainDir).Should().Be(true);
+            Directory.Exists(subDir1).Should().Be(false);
+        }
+
+        [Test]
+        public void RemoveEmptySubfolders_should_not_remove_nested_nonempty_folder()
+        {
+            var mainDir = GetTempFilePath();
+            var subDir1 = Path.Combine(mainDir, "depth1");
+            var subDir2 = Path.Combine(subDir1, "depth2");
+            var file = Path.Combine(subDir1, "file1.txt");
+            Directory.CreateDirectory(subDir2);
+            File.WriteAllText(file, "I should not be deleted");
+
+            Subject.RemoveEmptySubfolders(mainDir);
+
+            Directory.Exists(mainDir).Should().Be(true);
+            Directory.Exists(subDir1).Should().Be(true);
+            Directory.Exists(subDir2).Should().Be(false);
+            File.Exists(file).Should().Be(true);
+        }
+
         private void DoHardLinkRename(FileShare fileShare)
         {
             var sourceDir = GetTempFilePath();
diff --git a/src/NzbDrone.Common/Disk/DiskProviderBase.cs b/src/NzbDrone.Common/Disk/DiskProviderBase.cs
index a22aeabe6..39a1dfeea 100644
--- a/src/NzbDrone.Common/Disk/DiskProviderBase.cs
+++ b/src/NzbDrone.Common/Disk/DiskProviderBase.cs
@@ -145,7 +145,7 @@ namespace NzbDrone.Common.Disk
         {
             Ensure.That(path, () => path).IsValidPath();
 
-            return Directory.EnumerateDirectories(path).Empty();
+            return Directory.EnumerateFileSystemEntries(path).Empty();
         }
 
         public string[] GetDirectories(string path)
@@ -489,14 +489,21 @@ namespace NzbDrone.Common.Disk
 
         public void RemoveEmptySubfolders(string path)
         {
-            var subfolders = Directory.GetDirectories(path, "*", SearchOption.AllDirectories);
-            var files = GetFiles(path, SearchOption.AllDirectories);
-
-            foreach (var subfolder in subfolders)
+            // Depth first search for empty subdirectories
+            foreach (var subdir in Directory.EnumerateDirectories(path))
             {
-                if (files.None(f => subfolder.IsParentPath(f)))
+                RemoveEmptySubfolders(subdir);
+
+                if (Directory.EnumerateFileSystemEntries(subdir).Empty())
                 {
-                    DeleteFolder(subfolder, false);
+                    try
+                    {
+                        Directory.Delete(subdir, false);
+                    }
+                    catch (Exception ex)
+                    {
+                        Logger.Warn(ex, "Failed to remove empty directory {0}", subdir);
+                    }
                 }
             }
         }
diff --git a/src/NzbDrone.Core/MediaFiles/DiskScanService.cs b/src/NzbDrone.Core/MediaFiles/DiskScanService.cs
index 13fff69ef..1c2c67225 100644
--- a/src/NzbDrone.Core/MediaFiles/DiskScanService.cs
+++ b/src/NzbDrone.Core/MediaFiles/DiskScanService.cs
@@ -202,14 +202,12 @@ namespace NzbDrone.Core.MediaFiles
         {
             if (_configService.DeleteEmptyFolders)
             {
-                if (_diskProvider.GetFiles(path, SearchOption.AllDirectories).Empty())
+                _diskProvider.RemoveEmptySubfolders(path);
+
+                if (_diskProvider.FolderEmpty(path))
                 {
                     _diskProvider.DeleteFolder(path, true);
                 }
-                else
-                {
-                    _diskProvider.RemoveEmptySubfolders(path);
-                }
             }
         }