const {stableSort} = require('./_30s.js');

test('stableSort is a Function', () => {
  expect(stableSort).toBeInstanceOf(Function);
});
const arr = [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10];
const compare = () => 0;
test('Array is properly sorted', () => {
  expect(stableSort(arr, compare)).toEqual(arr);
});