anchor.diff:          expect(target.keys, [1, 2, 3]);
           expect(target.values, ['a', 'b', 'c']);
         });
  +      test('iterable converter (default key and value providers)', () {
  +        final target = ['a', 'b'].toBiMap();
  +        expect(target.keys, ['a', 'b']);
  +        expect(target.values, ['a', 'b']);
  +      });
       });
       group('accessing', () {
         test('indexed', () {
  
positive.code:           map.replaceAll('b', [3, 4, 5]);
            expect(map, hasLength(4));
            expect(collection, [3, 4, 5]);
          });
          test('clear', () {
            final map = ListMultimap.fromIterables(['a', 'b', 'b'], [1, 2, 3]);
            final collection = map['b'];
            map.clear();
            expect(map, isEmpty);
            expect(collection, isEmpty);
          });
          test('clear', () {
            final map = ListMultimap.fromIterables(['a', 'b', 'b'], [1, 2, 3]);
  
negative.code:       final root = createRoot<String, String, num>();
        expect(root.hasKeyAndValue, isFalse);
        expect(root.hasChildren, isFalse);
        expect(root.parts, isEmpty);
        final types = trie.entries.map((each) => each.runtimeType).toSet();
        expect(types.single, root.runtimeType);
      });
  