Mapper { @VisibleForOverride protected Predicate<R> requirement(CommandNode<T> command) { return (Predicate<R>) TRUE; }  CommandNode<R> map(CommandNode<T> command); static final Command<?> NONE; static final Predicate<?> TRUE; static final SuggestionProvider<?> EMPTY; }
@Test void predicate() { assertTrue(mapper.requirement(null).test(null)); }