### Question:
DNDListDOMHelper { static void setCSSWidth(final HTMLElement element, final int value) { element.style.setProperty("width", "calc(100% - " + value + "px)"); }   static final String DRAGGING; }### Answer:
@Test public void testSetCSSWidth() { element.style = mock(CSSStyleDeclaration.class); setCSSWidth(element, 321); verify(element.style).setProperty("width", "calc(100% - 321px)"); }