### Question:
JsFunctionBodyBuilder { public JsArriveHandlerBuilder whenCssSelectorArrives(String cssSelector) { return new JsArriveHandlerBuilder(cssSelector, this); } JsFunctionBodyBuilder(JsFunctionDeclarerBuilder jsFunctionDeclarerBuilder); JsCollector endBody(); JsArriveHandlerBuilder whenCssSelectorArrives(String cssSelector); JsFunctionBodyBuilder write(String string); JsLeaveHandlerBuilder whenCssSelectorLeaves(String cssSelector);  }### Answer:
@Test public void createsANotNullArriveHandler() { JsFunctionDeclarerBuilder jsFunctionDeclarerBuilder = mock(JsFunctionDeclarerBuilder.class); JsFunctionBodyBuilder jsFunctionBodyBuilder = new JsFunctionBodyBuilder(jsFunctionDeclarerBuilder); assertNotNull(jsFunctionBodyBuilder.whenCssSelectorArrives("#title")); }