How to unit test onCall firebase cloud functions?-CodePudding

I am trying to write my first unit test for a firebase cloud function, specifically the https.onCall function, which is used for the firebase mobile SDKs. So I tried writing it by using examples online and came to this result code:

import "jest";
import helloWorld from "../src/functions/helloworld";
import Message from "../src/types/message";

describe("helloworld", () => {
  test("it should run", () => {
    const req = { body: { data: {} } };
    const res = {
      on: (response: Message) => {
        expect(response).toBe({ text: "Hello from Firebase!", code: 200 });
      },
    };

    helloWorld(req as any, res as any);
  });
});

Just in case I did something wrong in the function itself, I will share the code of the function here:

import { logger, region, https } from "firebase-functions/v1";
import Message from "../types/message";

const helloWorldHandler = region("europe-west1").https.onCall((_, context) => {
  if (context.app == undefined) {
    throw new https.HttpsError("failed-precondition", "The function must be called from an App Check verified app.");
  }

  logger.info("Hello logs!", { structuredData: true });
  const message: Message = {
    text: "Hello from Firebase!",
    code: 200,
  };
  return message;
});

export default helloWorldHandler;

So the test itself runs but I run into the issue, that the result is different from what I am expecting with toBe

I receive the following error:

matcherResult: {
    actual: 'finish',
    expected: { text: 'Hello from Firebase!', code: 200 },
    message: '\x1B[2mexpect(\x1B[22m\x1B[31mreceived\x1B[39m\x1B[2m).\x1B[22mtoBe\x1B[2m(\x1B[22m\x1B[32mexpected\x1B[39m\x1B[2m) // Object.is equality\x1B[22m\n'  
      '\n'  
      'Expected: \x1B[32m{"code": 200, "text": "Hello from Firebase!"}\x1B[39m\n'  
      'Received: \x1B[31m"finish"\x1B[39m',
    name: 'toBe',
    pass: false
  }

I guess the on function on res is wrong and it should be different. Still, the only example firebase provides in their documentation is with a function that uses redirect, so I guess I need another keyword since on is not the right one. I also tried using the send keyword, but it did not work for me. Is there any specific function I need to add to the res for the OnCall to work, or do I have another general issue?

CodePudding user response：

The code above in general was not correct. With this code below my unit test works. Going to change the question name so others can find this easier:

import * as functions from "firebase-functions-test";
import helloWorldHandler from "../src/functions/helloworld";
import Message from "../src/types/message";

describe('Testing "helloWorld"', () => {
  it("test helloWorld if function works", async () => {
    const test = functions();
    const data = {};
    const context = {
      app: {},
    };
    const result: Message = await test.wrap(helloWorldHandler)(data, context);
    expect(result.code).toBe(200);
    expect(result.text).toBe("Hello from Firebase!");
  });
});