anchor.diff:      // Test all of them.
       group('a number of variadic children:', () {
         test('0', () {
  -        final instance = factory({...props});
  +        final instance = factory(props);
           expect(getChildren(instance), shouldAlwaysBeList ? [] : isNull);
         });
   
         test('1', () {
  -        final instance = factory({...props}, 1);
  +        final instance = factory(props, 1);
           expect(getChildren(instance), shouldAlwaysBeList ? [1] : 1);
         });
   
  
positive.code:     });
  
      test('an empty List', () {
        var instance = factory({...props}, []);
        expect(getChildren(instance), equals([]));
      });
  
      test('an Iterable', () {
        var instance = factory({...props}, new Iterable.generate(3, (int i) => '$i'));
        expect(getChildren(instance), equals(['0', '1', '2']));
      });
  
      test('an empty Iterable', () {
        var instance = factory({...props}, new Iterable.empty());
        expect(getChildren(instance), equals([]));
      });
    }
  
negative.code:     });
  
      test('a List', () {
        var instance = factory(props, [
          'one',
          'two',
        ]);
  