fix: Trigger correct notifications when moving directories (#866)

This pull request fixes directory move notifications in the file system watcher to trigger the correct events based on the destination path. The key change ensures that when a directory is moved outside the watched directory, a delete event is properly triggered instead of a rename event.

### Key changes:
- Fixed notification filter logic to use appropriate filters for different file system object types (files vs directories)
- Updated path matching logic to properly handle directory moves that cross watched directory boundaries
- Added comprehensive test coverage for directory move scenarios

Author: vbreuss

Source/Testably.Abstractions.Testing/FileSystem/FileSystemWatcherMock.cs

@@ -353,7 +353,9 @@ private bool MatchesFilter(ChangeDescription changeDescription)
 			if (!changeDescription.Path.StartsWith(fullPath,
 				_fileSystem.Execute.StringComparisonMode))
 			{
-				return false;
+				return changeDescription.ChangeType == WatcherChangeTypes.Renamed &&
+				       changeDescription.OldPath?.StartsWith(fullPath,
+					       _fileSystem.Execute.StringComparisonMode) == true;
 			}
 		}
 		else if (!string.Equals(
@@ -536,12 +538,28 @@ private string TransformPathAndName(
 		}
 
 		name = transformedName;
+		if (!_fileSystem.Path.IsPathRooted(Path))
+		{
+			string rootedWatchedPath = _fileSystem.Path.GetFullPath(Path);
+			if (path?.StartsWith(rootedWatchedPath, _fileSystem.Execute.StringComparisonMode) ==
+			    true)
+			{
+				path = _fileSystem.Path.Combine(Path, path.Substring(rootedWatchedPath.Length));
+			}
+		}
+
 		return path ?? "";
 	}
 
 	private void TriggerRenameNotification(ChangeDescription item)
 	{
-		if (_fileSystem.Execute.IsWindows)
+		if (!item.Path.StartsWith(Path, _fileSystem.Execute.StringComparisonMode) &&
+		    item.OldPath != null)
+		{
+			Deleted?.Invoke(this, ToFileSystemEventArgs(
+				WatcherChangeTypes.Deleted, item.OldPath, item.OldName));
+		}
+		else if (_fileSystem.Execute.IsWindows)
 		{
 			if (TryMakeRenamedEventArgs(item,
 				out RenamedEventArgs? eventArgs))
@@ -551,9 +569,9 @@ private void TriggerRenameNotification(ChangeDescription item)
 			else if (item.OldPath != null)
 			{
 				Deleted?.Invoke(this, ToFileSystemEventArgs(
-					item.ChangeType, item.OldPath, item.OldName));
+					WatcherChangeTypes.Deleted, item.OldPath, item.OldName));
 				Created?.Invoke(this, ToFileSystemEventArgs(
-					item.ChangeType, item.Path, item.Name));
+					WatcherChangeTypes.Created, item.Path, item.Name));
 			}
 		}
 		else
@@ -692,7 +710,8 @@ public WaitForChangedResultMock(
 		public bool TimedOut { get; }
 	}
 
-	internal sealed class ChangeDescriptionEventArgs(ChangeDescription changeDescription) : EventArgs
+	internal sealed class ChangeDescriptionEventArgs(ChangeDescription changeDescription)
+		: EventArgs
 	{
 		public ChangeDescription ChangeDescription { get; } = changeDescription;
 	}

Source/Testably.Abstractions.Testing/Storage/InMemoryStorage.cs

@@ -1028,7 +1028,7 @@ private bool IncludeItemInEnumeration(
 			ChangeDescription fileSystemChange =
 				_fileSystem.ChangeHandler.NotifyPendingChange(WatcherChangeTypes.Renamed,
 					container.Type,
-					NotifyFilters.FileName,
+					ToNotifyFilters(container.Type),
 					destination,
 					source);
 			if (_containers.TryRemove(source, out IStorageContainer? sourceContainer))

Tests/Testably.Abstractions.Testing.Tests/FileSystem/FileSystemWatcherMockTests.cs

@@ -299,7 +299,7 @@ public async Task RenamedEventArgs_ShouldUseDirectorySeparatorFromSimulatedFileS
 			fileSystem.File.WriteAllText(expectedOldFullPath, "foo");
 
 			using IFileSystemWatcher fileSystemWatcher =
-				fileSystem.FileSystemWatcher.New(parentDirectory);
+				fileSystem.FileSystemWatcher.New(fileSystem.Path.GetFullPath(parentDirectory));
 			using ManualResetEventSlim ms = new();
 			fileSystemWatcher.Renamed += (_, eventArgs) =>
 			{

Tests/Testably.Abstractions.Tests/FileSystem/FileSystemWatcher/NotifyFiltersTests.cs

@@ -611,6 +611,89 @@ public async Task NotifyFilter_MoveFile_ShouldTriggerChangedEventOnNotifyFilters
 		await That(result.OldName).IsEqualTo(FileSystem.Path.GetFileName(sourceName));
 	}
 
+	[Theory]
+	[InlineAutoData(NotifyFilters.DirectoryName)]
+	public async Task NotifyFilter_MoveDirectory_ShouldTriggerChangedEventOnNotifyFilters(
+		NotifyFilters notifyFilter, string sourceName, string destinationName)
+	{
+		SkipIfLongRunningTestsShouldBeSkipped();
+
+		FileSystem.Initialize();
+		FileSystem.Directory.CreateDirectory(sourceName);
+		RenamedEventArgs? result = null;
+		using ManualResetEventSlim ms = new();
+		using IFileSystemWatcher fileSystemWatcher =
+			FileSystem.FileSystemWatcher.New(BasePath);
+		fileSystemWatcher.Renamed += (_, eventArgs) =>
+		{
+			// ReSharper disable once AccessToDisposedClosure
+			try
+			{
+				result = eventArgs;
+				ms.Set();
+			}
+			catch (ObjectDisposedException)
+			{
+				// Ignore any ObjectDisposedException
+			}
+		};
+
+		fileSystemWatcher.NotifyFilter = notifyFilter;
+		fileSystemWatcher.IncludeSubdirectories = true;
+		fileSystemWatcher.EnableRaisingEvents = true;
+
+		FileSystem.Directory.Move(sourceName, destinationName);
+
+		await That(ms.Wait(ExpectSuccess, TestContext.Current.CancellationToken)).IsTrue();
+		await That(result).IsNotNull();
+		await That(result!.ChangeType).IsEqualTo(WatcherChangeTypes.Renamed);
+		await That(result.FullPath).IsEqualTo(FileSystem.Path.GetFullPath(destinationName));
+		await That(result.Name).IsEqualTo(FileSystem.Path.GetFileName(destinationName));
+		await That(result.OldFullPath).IsEqualTo(FileSystem.Path.GetFullPath(sourceName));
+		await That(result.OldName).IsEqualTo(FileSystem.Path.GetFileName(sourceName));
+	}
+
+	[Theory]
+	[InlineAutoData(NotifyFilters.DirectoryName)]
+	public async Task NotifyFilter_MoveDirectoryOutOfTheWatchedDirectory_ShouldTriggerChangedEventOnNotifyFilters(
+		NotifyFilters notifyFilter, string sourceName, string destinationName)
+	{
+		SkipIfLongRunningTestsShouldBeSkipped();
+
+		FileSystem.Initialize().WithSubdirectory("watched");
+		var sourcePath = FileSystem.Path.Combine("watched", sourceName);
+		FileSystem.Directory.CreateDirectory(sourcePath);
+		FileSystemEventArgs? result = null;
+		using ManualResetEventSlim ms = new();
+		using IFileSystemWatcher fileSystemWatcher =
+			FileSystem.FileSystemWatcher.New("watched");
+		fileSystemWatcher.Deleted += (_, eventArgs) =>
+		{
+			// ReSharper disable once AccessToDisposedClosure
+			try
+			{
+				result = eventArgs;
+				ms.Set();
+			}
+			catch (ObjectDisposedException)
+			{
+				// Ignore any ObjectDisposedException
+			}
+		};
+
+		fileSystemWatcher.NotifyFilter = notifyFilter;
+		fileSystemWatcher.IncludeSubdirectories = true;
+		fileSystemWatcher.EnableRaisingEvents = true;
+
+		FileSystem.Directory.Move(sourcePath, destinationName);
+
+		await That(ms.Wait(ExpectSuccess, TestContext.Current.CancellationToken)).IsTrue();
+		await That(result).IsNotNull();
+		await That(result!.ChangeType).IsEqualTo(WatcherChangeTypes.Deleted);
+		await That(result.FullPath).IsEqualTo(sourcePath);
+		await That(result.Name).IsEqualTo(sourceName);
+	}
+
 	[Theory]
 	[AutoData]
 	public async Task NotifyFilter_WriteFile_ShouldNotNotifyOnOtherFilters(string fileName)