public void FileNotExists()
 {
     Assert.ThrowsExact <ArgumentNullException>(() => Assert.FileNotExists(null as string));
     Assert.ThrowsExact <ArgumentNullException>(() => Assert.FileNotExists(null as FileInfo));
     Assert.DoesNotThrow(() => Assert.FileNotExists(NonExistingFile));
     Assert.DoesNotThrow(() => Assert.FileNotExists(NonExistingFileInfo));
     Assert.DoesNotThrow(() => Assert.FileNotExists(new FileInfo(NonExistingFile)));
     Assert.ThrowsExact <AssertionException>(() => Assert.FileNotExists(ExistingFile));
     Assert.ThrowsExact <AssertionException>(() => Assert.FileNotExists(ExistingFileInfo));
 }