text: import chai from 'chai'
  import difference from '../src/difference.js'
  
  const expect = chai.expect
  
  describe("Test difference.js", () => {
  
     it("([],[1]) = []", () => expect(difference()).to.eql([]));
     it("([2, 1]) = [2,1]", () => expect(difference([2, 1])).to.eql([2,1]));
  
     it("([2, 1], [2, 3]) = [1]", () => expect(difference([2, 1], [2, 3])).to.eql([1]));
     it("([1,2,3,4], [2, 3]) = [1, 4]", () => expect(difference([1,2,3,4], [2, 3])).to.eql([1,4]));
  })