eatvio_app/test/features/registration/registration_error_message_test.dart

import 'package:dio/dio.dart';
import 'package:eatvio_app/features/registration/registration_error_message.dart';
import 'package:flutter_test/flutter_test.dart';

void main() {
  group('registrationErrorMessage', () {
    test('returns string when error is String', () {
      expect(registrationErrorMessage('Some error'), 'Some error');
    });

    test('returns message from 422 DioException with message field', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
        response: Response(
          requestOptions: RequestOptions(path: ''),
          statusCode: 422,
          data: {'message': 'Validation failed'},
        ),
      );
      expect(registrationErrorMessage(error), 'Validation failed');
    });

    test('returns errors from 422 DioException with errors field', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
        response: Response(
          requestOptions: RequestOptions(path: ''),
          statusCode: 422,
          data: {
            'message': 'Validation error',
            'errors': {
              'email': ['Email уже используется'],
              'name': ['Имя обязательно'],
            },
          },
        ),
      );
      final result = registrationErrorMessage(error);
      expect(result, contains('Validation error'));
      expect(result, contains('Email уже используется'));
      expect(result, contains('Имя обязательно'));
    });

    test('returns data string for 422 with unknown format', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
        response: Response(
          requestOptions: RequestOptions(path: ''),
          statusCode: 422,
          data: {'unknown_key': 'value'},
        ),
      );
      expect(registrationErrorMessage(error), contains('Ошибка регистрации'));
    });

    test('returns DioException message for non-422 status', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
        message: 'Connection timeout',
        response: Response(
          requestOptions: RequestOptions(path: ''),
          statusCode: 500,
        ),
      );
      expect(registrationErrorMessage(error), 'Connection timeout');
    });

    test('returns DioException toString when message is null', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
      );
      expect(registrationErrorMessage(error), contains('DioException'));
    });

    test('returns toString for unknown error type', () {
      expect(registrationErrorMessage(42), '42');
      expect(registrationErrorMessage(Exception('Test')), contains('Test'));
    });

    test('handles 422 with empty errors list', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
        response: Response(
          requestOptions: RequestOptions(path: ''),
          statusCode: 422,
          data: {
            'message': 'Error',
            'errors': {
              'field': <String>[],
            },
          },
        ),
      );
      expect(registrationErrorMessage(error), 'Error');
    });

    test('handles 422 with non-Map response data', () {
      final error = DioException(
        requestOptions: RequestOptions(path: ''),
        response: Response(
          requestOptions: RequestOptions(path: ''),
          statusCode: 422,
          data: 'plain string error',
        ),
      );
      // Not a map, falls through to DioException handling
      expect(registrationErrorMessage(error), isNotEmpty);
    });
  });
}