### Question:
GenericServiceTaskEditorWidget extends Composite implements HasValue<GenericServiceTaskValue> { public void setServiceImplementationOptions(List<String> options) { clearSelect(implementation); options.forEach(option -> implementation.add(newOption(option, option))); }  @PostConstruct void init(); void setServiceImplementationOptions(List<String> options); void setReadOnly(boolean readOnly); @Override GenericServiceTaskValue getValue(); @Override void setValue(GenericServiceTaskValue value); @Override void setValue(GenericServiceTaskValue newValue, boolean fireEvents); @Override HandlerRegistration addValueChangeHandler(ValueChangeHandler<GenericServiceTaskValue> handler);  }### Answer:
@Test public void setServiceImplementationOptions() { List<String> options = widget.getImplementationOptions(); doNothing().when(widget).clearSelect(any(Select.class)); when(widget.newOption(any(String.class), any(String.class))).thenReturn(option); doNothing().when(implementation).add(any(Select.class)); widget.setServiceImplementationOptions(options); verify(implementation, times(2)).add(any()); }