Nestjs with Fastify e2e test with jest mocking is not working - node.js

Question

I have Nodejs API that use Fastify. The e2e test is written with jest.
Please find my e2e test. It works and test passes.
Here I find the response is same as the request parameter instead of mocking object.
The actual API respond the request parameter but here I am mocking different object but it is not using it for response.
I am not sure whether passing request body is correct for POST.
Why Jest mocking is not working. The similar mocking works for unit test.
import {
FastifyAdapter,
NestFastifyApplication,
} from '#nestjs/platform-fastify';
import { Test, TestingModule } from '#nestjs/testing';
import request from 'supertest';
import { AppModule } from '../src/app/app.module';
import Axios, { AxiosResponse } from 'axios';
import { HttpService } from '#nestjs/common';
import { Observable, of, observable } from 'rxjs';
import { OracleDBService } from 'synapse.bff.core';
describe('AppController (e2e)', () => {
let app: NestFastifyApplication;
let httpService: HttpService;
let oracleDBService: OracleDBService;
beforeEach(async () => {
const moduleFixture: TestingModule = await Test.createTestingModule({
imports: [AppModule],
}).compile();
app = moduleFixture.createNestApplication<NestFastifyApplication>(
new FastifyAdapter(),
);
httpService = moduleFixture.get<HttpService>(HttpService);
oracleDBService = moduleFixture.get<OracleDBService>(OracleDBService);
await app.init();
jest.setTimeout(30000);
});
it('/ (GET)', () => {
const data = [
{ name: 'item1', code: '100', category: 'cat1', price: 1250 },
{ name: 'item2', code: '101', category: 'cat1', price: 1250 },
{ name: 'item3', code: '102', category: 'cat1', price: 1250 },
{ name: 'item4', code: '103', category: 'cat1', price: 1250 },
];
const response: AxiosResponse<any> = {
data,
headers: {},
config: { url: 'http://localhost:3001/item/getitem' },
status: 200,
statusText: 'OK',
};
jest.spyOn(httpService, 'get').mockReturnValue(of(response));
return app
.inject({
method: 'GET',
url: '/item/100',
})
.then(onresponse =>
expect(JSON.parse(onresponse.payload)).toEqual(response.data),
);
});
it('/ (POST)', () => {
const data = {
Name: 'item1Mock',
Code: '500',
Category: 'cat1Mock',
Price: 9250,
};
const response: AxiosResponse<any> = {
data,
headers: {},
config: { url: 'http://localhost:3001/item/getitem' },
status: 200,
statusText: 'OK',
};
jest.spyOn(httpService, 'post').mockReturnValue(of(response));
return app
.inject({
method: 'POST',
url: '/item/create',
payload: {
body: {
Name: 'item1',
Code: '200',
Category: 'cat1',
Price: 1250,
},
},
})
.then(onResponse =>
expect(
JSON.parse(onResponse.payload).message.Detail.message[0].target.body,
).toEqual(response.data),
);
});
I am getting the following error
expect(received).toEqual(expected) // deep equality
- Expected
+ Received
Object {
- "Category": "cat1Mock",
- "Code": "500",
- "Name": "item1Mock",
- "Price": 9250,
+ "Category": "cat1",
+ "Code": "200",
+ "Name": "item1",
+ "Price": 1250,
}
90 | expect(
91 | JSON.parse(onResponse.payload).message.Detail.message[0].target.body,
> 92 | ).toEqual(response.data),
| ^
93 | );
94 | });
95 |
at item.controller.e2e-spec.ts:92:11