### Question:
ListArgumentSet implements ArgumentSet { @Override public boolean isEmpty() { return arguments.isEmpty(); } ListArgumentSet(List<String> arguments); @Override String get(int index); @Override int length(); @Override List<String> getAll(); @Override boolean isEmpty(); @Override boolean has(String argument); @Override String join(); @Override String[] toArray();  }### Answer:
@Test public void isEmpty() { assertFalse(listArgumentSet.isEmpty()); listArgumentSet = new ListArgumentSet(emptyList()); assertTrue(listArgumentSet.isEmpty()); }