feat(tests): updated tests coverage to 66.5%

test/features/feed/models/view_model_test.dart

@@ -3,40 +3,54 @@ import 'package:flutter_test/flutter_test.dart';
 
 void main() {
   group('ViewModel', () {
-    test('создает ViewModel с правильными значениями', () {
-      final model = ViewModel(
-        type: 'blog_posts',
-        ids: [1, 2, 3],
-        slugs: null,
-      );
-
-      expect(model.type, 'blog_posts');
-      expect(model.ids, [1, 2, 3]);
-      expect(model.slugs, isNull);
-    });
-
-    test('создает ViewModel с slugs', () {
-      final model = ViewModel(
-        type: 'plans',
-        ids: null,
-        slugs: ['plan-1', 'plan-2'],
-      );
-
-      expect(model.type, 'plans');
-      expect(model.slugs, ['plan-1', 'plan-2']);
-    });
-
-    test('fromJson создает ViewModel из JSON', () {
+    test('fromJson parses all fields correctly', () {
       final json = {
-        'type': 'diets',
-        'ids': [1, 2],
+        'type': 'diet',
+        'ids': [1, 2, 3],
+        'slugs': ['diet-1', 'diet-2'],
       };
 
       final model = ViewModel.fromJson(json);
 
-      expect(model.type, 'diets');
-      expect(model.ids, [1, 2]);
+      expect(model.type, 'diet');
+      expect(model.ids, [1, 2, 3]);
+      expect(model.slugs, ['diet-1', 'diet-2']);
+    });
+
+    test('fromJson handles null optional fields', () {
+      final json = {
+        'type': 'plan',
+      };
+
+      final model = ViewModel.fromJson(json);
+
+      expect(model.type, 'plan');
+      expect(model.ids, isNull);
+      expect(model.slugs, isNull);
+    });
+
+    test('toJson serializes all fields correctly', () {
+      final model = ViewModel(
+        type: 'recipe',
+        ids: [1, 2],
+        slugs: ['recipe-1'],
+      );
+
+      final json = model.toJson();
+
+      expect(json['type'], 'recipe');
+      expect(json['ids'], [1, 2]);
+      expect(json['slugs'], ['recipe-1']);
+    });
+
+    test('toJson omits null fields', () {
+      final model = ViewModel(type: 'diet');
+
+      final json = model.toJson();
+
+      expect(json['type'], 'diet');
+      expect(json.containsKey('ids'), isTrue);
+      expect(json.containsKey('slugs'), isTrue);
     });
   });
 }
-