VirtualFS/VirtualFS.Tests/RootFileSystemTest.cs

using VirtualFS.Implementation;
using VirtualFS.Physical;

namespace VirtualFS.Tests;

public sealed class RootFileSystemTests : IDisposable
{
    private readonly string _realRootPath;
    private readonly RootFileSystem _root;

    public RootFileSystemTests()
    {
        _realRootPath = System.IO.Path.Combine(System.IO.Path.GetTempPath(), "VirtualFS.Tests", Guid.NewGuid().ToString("N"));
        System.IO.Directory.CreateDirectory(_realRootPath);

        _root = new RootFileSystem();
        _root.Mount(new PhysicalFileSystem(new System.IO.DirectoryInfo(_realRootPath)), (Path)"/");
    }

    [Fact]
    public void EnumerateMergesMountedEntriesWithoutDuplicates()
    {
        var sharedRoot = new System.IO.DirectoryInfo(_realRootPath);
        System.IO.File.WriteAllText(System.IO.Path.Combine(_realRootPath, "first.txt"), "first");

        var root = new RootFileSystem();
        root.Mount(new PhysicalFileSystem(sharedRoot), (Path)"/");
        root.Mount(new PhysicalFileSystem(sharedRoot), (Path)"/");

        Assert.Equal(new PhysicalFileSystem(sharedRoot).GetEntries("/").Count(), root.GetEntries("/").Count());
    }

    [Fact]
    public void DirectoryCreateAndDeleteReflectsOnMountedPhysicalFileSystem()
    {
        var dir = _root.Root.Create("Test");
        var expectedPath = System.IO.Path.Combine(_realRootPath, "Test");

        Assert.True(System.IO.Directory.Exists(expectedPath));

        dir.Delete();

        Assert.False(System.IO.Directory.Exists(expectedPath));
    }

    public void Dispose()
    {
        if (System.IO.Directory.Exists(_realRootPath))
            System.IO.Directory.Delete(_realRootPath, recursive: true);
    }
}