Apollo Client Test Sample

client-test.ts

import { ApolloClient } from 'apollo-client';
import { InMemoryCache } from 'apollo-cache-inmemory';
import { withClientState } from 'apollo-link-state';
import { ApolloLink } from 'apollo-link';
import gql from 'graphql-tag';
import 'jest';



describe('Apollo Client tests', () => {
    const query = gql`
    {
      field @client
    }
  `;


    let count = 0;
    const local = withClientState({
        resolvers: {
            ClassName: {
                subFunction: () => {
                    return 2;
                },
                isSubFunction: () => {
                    return true;
                },
            },
            Query: {
                field: () => {
                    count++;
                    return 1;
                },
                className: () => ({
                    __typename: 'ClassName',
                }),
            },
        },
        defaults: {

        },
    });

    const client = new ApolloClient({
        cache: new InMemoryCache(),
        link: local,
    });

    it('test', async () => {
        const result = await client.query({ query });
        expect({ ...result.data }).toMatchObject({ field: 1 });
        expect(count).toBe(1);
    });

    it('test ClassName', async () => {
        const classQuery = gql`
        {
            className @client {
                isSubFunction
            }
        }
        `;
        const result = await client.query({ query: classQuery });
        expect({ ...result.data }).toMatchObject({ className: { isSubFunction: true, __typename: 'ClassName' } });
    });

    it(' service', async () => {
        const isSubFunction = gql`
        {
            className @client {
                isSubFunction
            }
        }
        `;
        const subFunction = gql`
                {
                    className @client {
                        subFunction
                    }
                }
                `;

        class NewService {
            public async isSubFunction() {
                const result = await client.query({ query: isSubFunction });
                return result.data.className.isSubFunction;
            }
            public async subFunction() {
                const result = await client.query({ query: subFunction });
                return result.data.className.subFunction;
            }
        }

        const service = new NewService();
        expect(await service.isSubFunction()).toBe(true);

    });

});