import { expect } from 'chai' ; import { addAllToSet } from './add-all-to-set.function' ; describe ( 'addAllToSet' , ( ) => { it ( 'should create a set that has all the elements' , ( ) => { const set = addAllToSet ( [ 1 , 1 , 2 , 3 ] ) ; expect ( set . size ) . to . equal ( 3 ) ; } ) ; } ) ;