Improve code quality and test performance

src/Ramstack.FileSystem.Abstractions/VirtualNode.cs

@@ -41,7 +41,7 @@ public abstract class VirtualNode
     /// <param name="path">The full path of the file or directory.</param>
     protected VirtualNode(string path)
     {
-        Debug.Assert(path == VirtualPath.Normalize(path));
+        Debug.Assert(VirtualPath.IsNormalized(path));
         FullName = path;
     }
 

src/Ramstack.FileSystem.Abstractions/VirtualNodeProperties.cs

@@ -9,11 +9,17 @@ namespace Ramstack.FileSystem;
 public sealed class VirtualNodeProperties
 {
     /// <summary>
-    /// Gets an instance of <see cref="VirtualNodeProperties"/> that represents a node with no data or an unavailable state.
+    /// Gets an instance of <see cref="VirtualNodeProperties"/> that represents a node with an unavailable state.
     /// </summary>
     public static VirtualNodeProperties Unavailable { get; } =
         new VirtualNodeProperties(default, default, default, -1);
 
+    /// <summary>
+    /// Gets an instance of <see cref="VirtualNodeProperties"/> that represents a node with no data.
+    /// </summary>
+    public static VirtualNodeProperties None { get; } =
+        new VirtualNodeProperties(default, default, default, 0);
+
     /// <summary>
     /// Gets the time when the current file or directory was created.
     /// </summary>

src/Ramstack.FileSystem.Adapters/VirtualDirectoryAdapter.cs

@@ -46,8 +46,8 @@ protected override void RefreshCore()
     protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken)
     {
         var properties = _file?.Exists ?? _directory!.Exists
-            ? VirtualNodeProperties.CreateDirectoryProperties(default, default, default)
-            : null;
+            ? VirtualNodeProperties.None
+            : VirtualNodeProperties.Unavailable;
 
         return new ValueTask<VirtualNodeProperties?>(properties);
     }

src/Ramstack.FileSystem.Amazon/S3Directory.cs

@@ -24,15 +24,12 @@ internal sealed class S3Directory : VirtualDirectory
     public S3Directory(AmazonS3FileSystem fileSystem, string path) : base(path)
     {
         _fs = fileSystem;
-        _prefix = FullName == "/" ? "" : $"{FullName[1..]}/";
+        _prefix = path == "/" ? "" : $"{path[1..]}/";
     }
 
     /// <inheritdoc />
-    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken)
-    {
-        var properties = VirtualNodeProperties.CreateDirectoryProperties(default, default, default);
-        return new ValueTask<VirtualNodeProperties?>(properties);
-    }
+    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken) =>
+        new ValueTask<VirtualNodeProperties?>(VirtualNodeProperties.None);
 
     /// <inheritdoc />
     protected override ValueTask CreateCoreAsync(CancellationToken cancellationToken) =>

src/Ramstack.FileSystem.Amazon/S3UploadStream.cs

@@ -91,13 +91,6 @@ public override int Read(byte[] buffer, int offset, int count)
         return 0;
     }
 
-    /// <inheritdoc />
-    public override long Seek(long offset, SeekOrigin origin)
-    {
-        Error_NotSupported();
-        return 0;
-    }
-
     /// <inheritdoc />
     public override void Write(byte[] buffer, int offset, int count) =>
         Write(buffer.AsSpan(offset, count));
@@ -139,6 +132,13 @@ public override async ValueTask WriteAsync(ReadOnlyMemory<byte> buffer, Cancella
         }
     }
 
+    /// <inheritdoc />
+    public override long Seek(long offset, SeekOrigin origin)
+    {
+        Error_NotSupported();
+        return 0;
+    }
+
     /// <inheritdoc />
     public override void SetLength(long value) =>
         Error_NotSupported();

src/Ramstack.FileSystem.Azure/AzureDirectory.cs

@@ -27,11 +27,8 @@ public AzureDirectory(AzureFileSystem fileSystem, string path) : base(path) =>
         _fs = fileSystem;
 
     /// <inheritdoc />
-    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken)
-    {
-        var properties = VirtualNodeProperties.CreateDirectoryProperties(default, default, default);
-        return new ValueTask<VirtualNodeProperties?>(properties);
-    }
+    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken) =>
+        new ValueTask<VirtualNodeProperties?>(VirtualNodeProperties.None);
 
     /// <inheritdoc />
     protected override ValueTask<bool> ExistsCoreAsync(CancellationToken cancellationToken) =>

src/Ramstack.FileSystem.Composite/CompositeDirectory.cs

@@ -23,11 +23,8 @@ public CompositeDirectory(CompositeFileSystem fileSystem, string path) : base(pa
         _fs = fileSystem;
 
     /// <inheritdoc />
-    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken)
-    {
-        var properties = VirtualNodeProperties.CreateDirectoryProperties(default, default, default);
-        return new ValueTask<VirtualNodeProperties?>(properties);
-    }
+    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken) =>
+        new ValueTask<VirtualNodeProperties?>(VirtualNodeProperties.None);
 
     /// <inheritdoc />
     protected override ValueTask CreateCoreAsync(CancellationToken cancellationToken) =>

src/Ramstack.FileSystem.Prefixed/PrefixedFileSystem.cs

@@ -130,11 +130,8 @@ public ArtificialDirectory(PrefixedFileSystem fileSystem, string path, VirtualDi
             (_fs, _directory) = (fileSystem, directory);
 
         /// <inheritdoc />
-        protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken)
-        {
-            var properties = VirtualNodeProperties.CreateDirectoryProperties(default, default, default);
-            return new ValueTask<VirtualNodeProperties?>(properties);
-        }
+        protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken) =>
+            new ValueTask<VirtualNodeProperties?>(VirtualNodeProperties.None);
 
         /// <inheritdoc />
         protected override ValueTask CreateCoreAsync(CancellationToken cancellationToken) =>

src/Ramstack.FileSystem.Zip/ZipDirectory.cs

@@ -20,16 +20,13 @@ internal sealed class ZipDirectory : VirtualDirectory
     /// Initializes a new instance of the <see cref="ZipDirectory"/> class.
     /// </summary>
     /// <param name="fileSystem">The file system associated with this directory.</param>
-    /// <param name="path">The path of directory.</param>
+    /// <param name="path">The path of the directory.</param>
     public ZipDirectory(ZipFileSystem fileSystem, string path) : base(path) =>
         _fileSystem = fileSystem;
 
     /// <inheritdoc />
-    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken)
-    {
-        var properties = VirtualNodeProperties.CreateDirectoryProperties(default, default, default);
-        return new ValueTask<VirtualNodeProperties?>(properties);
-    }
+    protected override ValueTask<VirtualNodeProperties?> GetPropertiesCoreAsync(CancellationToken cancellationToken) =>
+        new ValueTask<VirtualNodeProperties?>(VirtualNodeProperties.None);
 
     /// <inheritdoc />
     protected override ValueTask<bool> ExistsCoreAsync(CancellationToken cancellationToken) =>

tests/Ramstack.FileSystem.Specification.Tests/VirtualFileSystemSpecificationTests.cs

@@ -65,8 +65,8 @@ public async Task FileTree_VirtualNode_FileSystem_MatchesIssuingFileSystemRefere
         using var fs = GetFileSystem();
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var node in fs.GetFileNodesAsync("/", "**"))
         {
@@ -85,8 +85,8 @@ public async Task Exists_ReturnsTrue_For_ExistingFile()
         using var fs = GetFileSystem();
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var node in fs.GetFileNodesAsync("/", "**"))
         {
@@ -114,8 +114,8 @@ public async Task File_OpenRead_ReturnsReadableStream()
         using var fs = GetFileSystem();
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
         {
@@ -148,8 +148,8 @@ public async Task File_OpenWrite_ReturnsWritableStream()
             return;
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
         {
@@ -205,8 +205,8 @@ public async Task File_Write_OverwritesContent_When_OverwriteIsTrue()
             return;
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
         {
@@ -233,8 +233,8 @@ public async Task File_Write_ThrowsException_For_ExistingFile_When_OverwriteIsFa
             return;
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
         {
@@ -324,8 +324,8 @@ public async Task File_Readonly_OpenWrite_ThrowsException()
             return;
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
         {
@@ -362,8 +362,8 @@ public async Task File_Readonly_Write_ThrowsException()
             return;
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
         {
@@ -395,8 +395,8 @@ public async Task File_Readonly_Delete_ThrowsException()
             return;
 
         Assert.That(
-            await fs.GetFilesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetFilesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var file in fs.GetFilesAsync("/", "**"))
             Assert.That(() => file.DeleteAsync(), Throws.Exception);
@@ -705,8 +705,8 @@ public async Task Directory_Create_For_ExistingDirectory()
             return;
 
         Assert.That(
-            await fs.GetDirectoriesAsync("/", "**").CountAsync(),
-            Is.Not.Zero);
+            await fs.GetDirectoriesAsync("/", "**").AnyAsync(),
+            Is.True);
 
         await foreach (var directory in fs.GetDirectoriesAsync("/", "**"))
             await directory.CreateAsync();