import { expect } from "chai" ; import * as helpers from "." ; test ( "allKeys()" , function ( ) { const obj1 = { a : "1" } ; const obj2 = { b : "1" } ; const obj3 = { c : "1" } ; const actual = helpers . allKeys ( obj1 , obj2 , obj3 ) ; expect ( actual ) . to . eql ( [ "a" , "b" , "c" ] ) ; } ) ;