rely/test/integrations/backend/backend_models_serialization_test.dart

import 'package:flutter_test/flutter_test.dart';
import 'package:relationship_saver/integrations/backend/models/backend_models.dart';

void main() {
  test('ChangeEnvelope roundtrip serialization', () {
    final ChangeEnvelope source = ChangeEnvelope(
      schemaVersion: 1,
      entityType: 'person',
      entityId: 'p1',
      op: ChangeOperation.upsert,
      modifiedAt: DateTime.utc(2026, 2, 1),
      clientMutationId: 'cm-1',
      payload: const <String, dynamic>{'name': 'Alex'},
    );

    final ChangeEnvelope decoded = ChangeEnvelope.fromJson(source.toJson());

    expect(decoded, source);
  });

  test('SignalsFeed roundtrip serialization', () {
    final SignalsFeed source = SignalsFeed(
      cursor: 'c1',
      items: <SignalItem>[
        SignalItem(
          id: 's1',
          type: 'deal',
          title: 'Coffee discount',
          createdAt: DateTime.utc(2026, 2, 2, 10),
          metadata: const <String, dynamic>{'merchant': 'Cafe'},
        ),
      ],
    );

    final SignalsFeed decoded = SignalsFeed.fromJson(source.toJson());

    expect(decoded, source);
  });
}