Nexus Tutorial Part 4. Testing your API fails npm run test

I’m working through the Nexus tutorial and encounter an error when running the command “npm run test”. I have included a screenshot of the terminal output of the command and can’t seem to figure out the problem.

I have the following versions installed in my package.json

"dependencies": {
    "apollo-server": "^2.22.2",
    "graphql": "^15.5.0",
    "nexus": "^1.0.0"
  },
  "devDependencies": {
    "@types/jest": "^26.0.22",
    "get-port": "^5.1.1",
    "graphql-request": "^3.4.0",
    "jest": "^26.6.3",
    "ts-jest": "^26.5.4",
    "ts-node-dev": "^1.1.6",
    "typescript": "^4.2.3"
  }

Perhaps an important note, the tutorial also misses including an export statement in the server.ts file located in /api/server.ts. The export statement was not included in any of the previous tutorial chapters but is imported as a module in tests/__helper.ts on line 4.

[raleigh9123]

This did solve the problem I encountered! Thank you.

When running the command again, I did receive an error that Jest could not find the node module “Prettier” Installing prettier as a dev dependency cleared this error and the test runs successfully.

[ruheni]

Hi @raleigh9123 👋🏾

Thank you for creating this issue. I tested it locally and ran into the same issue.

Perhaps an important note, the tutorial also misses including an export statement in the server.ts file located in /api/server.ts.

You are right, this is one of the fixes to the tutorial.

I updated the tutorial recently and I have a hunch it broke the tests.

Update your server.ts file to resemble this:

import { ApolloServer } from 'apollo-server'
import { schema } from './schema'
import { context } from './context'

export const server = new ApolloServer({ schema, context })

Create app.ts file in the api folder and import server as follows:

 import { server } from "./server";

server.listen().then(({ url }) => {
  console.log(`🚀 Server ready at ${url}`)
})

Lastly, update your package.json scripts to point the dev script to app.ts:

  "scripts": {
    "dev": "ts-node-dev --transpile-only --no-notify api/app.ts",
    "build": "tsc",
    "generate": "ts-node --transpile-only api/schema",
    "test": "npm run generate && jest"
  },

Re-run your tests and let me know if you run into any issues. 🙂

We’ll update the tutorial soon fixing this error.