import assert from 'assert';
import lodashStable from 'lodash';
import { falsey, args, slice, symbol, realm } from './utils.js';
import isNull from '../isNull.js';

describe('isNull', function() {
  it('should return `true` for `null` values', function() {
    assert.strictEqual(isNull(null), true);
  });

  it('should return `false` for non `null` values', function() {
    var expected = lodashStable.map(falsey, function(value) {
      return value === null;
    });

    var actual = lodashStable.map(falsey, function(value, index) {
      return index ? isNull(value) : isNull();
    });

    assert.deepStrictEqual(actual, expected);

    assert.strictEqual(isNull(args), false);
    assert.strictEqual(isNull([1, 2, 3]), false);
    assert.strictEqual(isNull(true), false);
    assert.strictEqual(isNull(new Date), false);
    assert.strictEqual(isNull(new Error), false);
    assert.strictEqual(isNull(_), false);
    assert.strictEqual(isNull(slice), false);
    assert.strictEqual(isNull({ 'a': 1 }), false);
    assert.strictEqual(isNull(1), false);
    assert.strictEqual(isNull(/x/), false);
    assert.strictEqual(isNull('a'), false);
    assert.strictEqual(isNull(symbol), false);
  });

  it('should work with nulls from another realm', function() {
    if (realm.object) {
      assert.strictEqual(isNull(realm.null), true);
    }
  });
});