Modernize project targets and Docker test flow

VirtualFS.Tests/Physical/PhysicalFileSystemTests.cs

@@ -1,14 +1,31 @@
 using VirtualFS.Physical;
 
-namespace VirtualFS.Tests.Physical
+namespace VirtualFS.Tests.Physical;
+
+public sealed class PhysicalFileSystemTests : IDisposable
 {
-    [TestClass]
-    public class PhysicalFileSystemTests
+    private readonly string _rootPath;
+    private readonly PhysicalFileSystem _fileSystem;
+
+    public PhysicalFileSystemTests()
     {
-        [TestMethod]
-        public void TestEnumerate()
-        {
-            Assert.IsTrue(new PhysicalFileSystem(new DirectoryInfo("C:\\")).GetEntries("/").Count() > 0);
-        }
+        _rootPath = System.IO.Path.Combine(System.IO.Path.GetTempPath(), "VirtualFS.Physical.Tests", Guid.NewGuid().ToString("N"));
+        System.IO.Directory.CreateDirectory(_rootPath);
+        System.IO.File.WriteAllText(System.IO.Path.Combine(_rootPath, "entry.txt"), "content");
+        System.IO.Directory.CreateDirectory(System.IO.Path.Combine(_rootPath, "nested"));
+
+        _fileSystem = new PhysicalFileSystem(new DirectoryInfo(_rootPath));
     }
-}
+
+    [Fact]
+    public void EnumerateReturnsEntriesFromMountedDirectory()
+    {
+        Assert.True(_fileSystem.GetEntries("/").Count() > 0);
+    }
+
+    public void Dispose()
+    {
+        if (System.IO.Directory.Exists(_rootPath))
+            System.IO.Directory.Delete(_rootPath, recursive: true);
+    }
+}