e2e testing not working with fastify V3

Bug Report

Original issue here https://github.com/fastify/help/issues/228. While the workaround in that thread works, it leaves open handles and has to hardcode port number. Also, they seem to conclude that something in app.init has to be changed.

Current behavior

    TypeError: Cannot read property 'length' of undefined

      at next (../node_modules/fastify/lib/route.js:374:32)
      at preParsingHookRunner (../node_modules/fastify/lib/route.js:405:3)
      at runPreParsing (../node_modules/fastify/lib/route.js:356:5)
      at Object.routeHandler [as handler] (../node_modules/fastify/lib/route.js:334:7)
      at Router.lookup (../node_modules/find-my-way/index.js:356:14)

Input Code

main.ts

import { NestFactory } from '@nestjs/core';
import {
  FastifyAdapter,
  NestFastifyApplication,
} from '@nestjs/platform-fastify';
import { AppModule } from './app.module';

async function bootstrap() {
  const app = await NestFactory.create<NestFastifyApplication>(
    AppModule,
    new FastifyAdapter(),
  );
  await app.listen(3000);
}
bootstrap();

app.e2e-spec.ts

import { Test, TestingModule } from '@nestjs/testing';
import { INestApplication } from '@nestjs/common';
import * as request from 'supertest';
import { AppModule } from './../src/app.module';
import { FastifyAdapter } from '@nestjs/platform-fastify';

describe('AppController (e2e)', () => {
  let app: INestApplication;

  beforeEach(async () => {
    const moduleFixture: TestingModule = await Test.createTestingModule({
      imports: [AppModule],
    }).compile();

    app = moduleFixture.createNestApplication(new FastifyAdapter());
    await app.init();
  });

  it('/ (GET)', () => {
    return request(app.getHttpServer())
      .get('/')
      .expect(200)
      .expect('Hello World!');
  });
});

Expected behavior

Test pass. (It works as expected if using fastify V2 and @nestjs/platform-fastify@7.2)

Possible Solution

Environment

Nest version: X.Y.Z

 
For Tooling issues:
- Node version: 7.4.2
- Platform:   Ubuntu

Others:

[jmcdo29]

Use FastifyNestApplication instead of INestApplication. You can cast this type as necessary. You can see an example here

[sramteare-chwy]

@Summon528 Please share an example here. I have similar problem, using fastify.inject is not recognized on INestApplication Property 'inject' does not exist on type 'INestApplication'.