@jetshop/core/helpers/getErrorDetail.test.js

import { ApolloError } from 'apollo-server-core';
import getErrorDetail from './getErrorDetail';

describe('GetErrorDetail', () => {
  describe('codes', () => {
    it('returns an empty array if given an empty object', () => {
      const codes = getErrorDetail({}).codes;

      expect(codes).toEqual([]);
    });
    it('returns an array of codes, filtering out errors with no graphQLErrors attached', () => {
      const codes = getErrorDetail(error).codes;

      expect(codes).toEqual(
        expect.arrayContaining([
          'UnableToSubscribeToNewsletter',
          'SomeOtherError'
        ])
      );
      expect(codes).toHaveLength(2);
    });
  });
});

const graphQLErrors = [
  {
    message: '',
    extensions: {
      code: 'UnableToSubscribeToNewsletter'
    }
  },
  {
    message: '',
    extensions: {
      code: 'SomeOtherError'
    }
  },
  {
    message: 'wow'
  }
];

// Create a mock ApolloError
const error = new ApolloError(null, null, { graphQLErrors });