Jest doesn't catch error, when thrown from async/await function - node.js

Question

Im testing some functions with MongoDB and Mongoose. For the tests i'm using Jest and mongo-memory-server. The function createUser(arg1, arg2) should throw a TypeError if there already exists a user with that discord id in the database.
createUser(arg1, arg2)
async function createUser(disc_id, moodleToken) {
const profileData = await fetchUser(disc_id);
if (profileData) {
throw TypeError("The account already exist in the database!");
}
const newUser = new profileModel({
discord_id: disc_id,
moodle_token: moodleToken,
})
await newUser.save();
return {
userId: newUser._id
};
}
fetchUser(disc_id) returns whether a user with the same discord id is found or not.
When testing with Jest i created the following test which passes just fine:
it("Should create a new user", async () => {
const discord_id = "3452357445";
const moodle_token = "34ffDSE8439Ujfe8f3jj";
const { userId } = await createUser(discord_id, moodle_token);
const user = await profileSchema.findById(userId);
expect(user.discord_id).toEqual(discord_id);
expect(user.moodle_token).toEqual(moodle_token);
})
Now i want to test if the TypeError is thrown when trying to create a new user, with the same discord id, i tried the following without any success:
describe("Error when", () => {
it("an existing matches discord id", async () => {
const discord_id = "3452357445";
const moodle_token = "34ffDSE8439Ujfe8f3jj";
await createUser(discord_id, moodle_token)
await expect(async () => {
createUser(discord_id, moodle_token);
}).rejects.toThrow(TypeError("The account already exist in the database!"))
})
})
When running the tests this is the output from the console:
FAIL test/manageUserDB.test.js
Create new user
✓ Should create a new user (66 ms)
Error when
✕ an existing matches discord id (3 ms)
● Create new user › Error when › an existing matches discord id
TypeError: The account already exist in the database!
11 |
12 | if (profileData) {
> 13 | throw TypeError("The account already exist in the database!");
| ^
14 | }
15 | const newUser = new profileModel({
16 | discord_id: disc_id,
at createUser (BoodleDB/manageUserDB.js:13:15)
at Object.<anonymous> (test/manageUserDB.test.js:29:13)
Test Suites: 1 failed, 1 total
Tests: 1 failed, 1 passed, 2 total
Snapshots: 0 total
Time: 0.6 s, estimated 1 s
Ran all test suites matching /.\/test/i.
EDIT
function fetchUser (disc_id) {
return profileModel.findOne({ discord_id: disc_id });
}

Answer 1

You need to await when you call createUser.
await expect(async () => {
await createUser(discord_id, moodle_token);
}).rejects.toThrow(TypeError("The account already exist in the database!"))