text: import { DESCRIPTORS, NATIVE, STRICT } from '../helpers/constants';
  
  QUnit.test('Array#fill', assert => {
    const { fill } = Array.prototype;
    assert.isFunction(fill);
    assert.arity(fill, 1);
    assert.name(fill, 'fill');
    assert.looksNative(fill);
    assert.nonEnumerable(Array.prototype, 'fill');
    const array = new Array(5);
    assert.strictEqual(array.fill(5), array);
    assert.deepEqual(Array(5).fill(5), [5, 5, 5, 5, 5]);
    assert.deepEqual(Array(5).fill(5, 1), [undefined, 5, 5, 5, 5]);
    assert.deepEqual(Array(5).fill(5, 1, 4), [undefined, 5, 5, 5, undefined]);
    assert.deepEqual(Array(5).fill(5, 6, 1), [undefined, undefined, undefined, undefined, undefined]);
    assert.deepEqual(Array(5).fill(5, -3, 4), [undefined, undefined, 5, 5, undefined]);
    assert.arrayEqual(fill.call({ length: 5 }, 5), [5, 5, 5, 5, 5]);
    if (STRICT) {
      assert.throws(() => fill.call(null, 0), TypeError);
      assert.throws(() => fill.call(undefined, 0), TypeError);
    }
    if (NATIVE && DESCRIPTORS) {
      assert.notThrows(() => fill.call(Object.defineProperty({
        length: -1,
      }, 0, {
        set() {
          throw Error();
        },
      })), 'uses ToLength');
    }
    assert.ok('fill' in Array.prototype[Symbol.unscopables], 'In Array#@@unscopables');
  });
  