public void WriteAllBytesShouldOverwriteHiddenFile() { var path = Path.GetTempFileName(); File.WriteAllText(path, "hi there"); File.SetAttributes(path, FileAttributes.Hidden); fileSystem.WriteAllBytes(path, Encoding.ASCII.GetBytes("hi")); Assert.AreEqual("hi", File.ReadAllText(path)); Assert.AreNotEqual(0, File.GetAttributes(path) & FileAttributes.Hidden); }