Mapper { @VisibleForOverride protected @Nullable SuggestionProvider<R> suggestions(ArgumentCommandNode<T, ?> command) { return null; }  CommandNode<R> map(CommandNode<T> command); static final Command<?> NONE; static final Predicate<?> TRUE; static final SuggestionProvider<?> EMPTY; }
@Test void suggestions() { assertNull(mapper.suggestions(null)); }