fix: FileSystemInitializer supports nested directories (#376)

Initializing the file system with nested `DirectoryDescriptions` now
creates the correct nested path.

Author: vbreuss

Source/Testably.Abstractions.Testing/FileSystemInitializer/FileSystemInitializer.cs

@@ -145,7 +145,7 @@ private IDirectoryInfo WithDirectory(DirectoryDescription directory)
 
 		if (directory.Children.Length > 0)
 		{
-			DirectoryInitializer<TFileSystem> subdirectoryInitializer = new(this, directoryInfo);
+			FileSystemInitializer<TFileSystem> subdirectoryInitializer = new(this, directoryInfo);
 			foreach (FileSystemInfoDescription children in directory.Children)
 			{
 				subdirectoryInitializer.WithFileOrDirectory(children);

Tests/Testably.Abstractions.Testing.Tests/FileSystemInitializer/FileSystemInitializerTests.cs

@@ -1,4 +1,5 @@
 using System.IO;
+using System.Linq;
 using Testably.Abstractions.Testing.FileSystemInitializer;
 
 namespace Testably.Abstractions.Testing.Tests.FileSystemInitializer;
@@ -21,6 +22,24 @@ public void With_DirectoryDescriptions_ShouldCreateDirectories(
 		}
 	}
 
+	[Theory]
+	[AutoData]
+	public void With_DirectoryDescriptions_WithSubdirectories_ShouldCreateDirectories(
+		string parent, DirectoryDescription[] directories)
+	{
+		DirectoryDescription directoryDescription = new(parent,
+			directories.Cast<FileSystemInfoDescription>().ToArray());
+		MockFileSystem fileSystem = new();
+		IFileSystemInitializer<MockFileSystem> sut = fileSystem.Initialize();
+
+		sut.With(directoryDescription);
+
+		foreach (DirectoryDescription directory in directories)
+		{
+			fileSystem.Should().HaveDirectory(Path.Combine(parent, directory.Name));
+		}
+	}
+
 	[Theory]
 	[AutoData]
 	public void With_FileDescription_WithBytes_ShouldCreateFileContent(string name, byte[] bytes)