t.Fatalf("Failed to write header: %s", err)
	}
	if _, err := tw.Write([]byte("fooo")); err != nil {
		t.Fatalf("Failed to write the file's data: %s", err)
	}
	tw.Close()

	tr := NewReader(&buffer)

	for {
		header, err := tr.Next()
		if err == io.EOF {
			break
		}
		if err != nil {
			t.Fatalf("Failed to read header: %s", err)
		}

	dw, err := w.Create("dir/")
	if err != nil {
		t.Fatal(err)
	}
	if _, err := dw.Write(nil); err != nil {
		t.Errorf("Write(nil) to directory: got %v, want nil", err)
	}
	if _, err := dw.Write([]byte("hello")); err == nil {
		t.Error(`Write("hello") to directory: got nil error, want non-nil`)
	}
}

func TestWriterDirAttributes(t *testing.T) {
	var buf bytes.Buffer
	w := NewWriter(&buf)