How to upload files when unit testing firebase storage security rules? - node.js

Question

I have a bucket into which users can upload audio files, and my goal is to test that it is working as expected. But when I try to use the "#firebase/rules-unit-testing" library to upload a test file into the emulator the upload gets stuck and makes no progress.
Rules
rules_version = '2';
service firebase.storage {
match /b/{bucket}/o {
match /{allPaths=**} {
allow read, write: if false;
}
match /audio/{audioFileID} {
allow create: if request.auth != null && request.resource.contentType.matches('audio/(flac|wav)');
}
}
}
Test code
import {
assertFails,
assertSucceeds,
initializeTestEnvironment,
RulesTestEnvironment,
} from "#firebase/rules-unit-testing";
import { test, beforeAll, beforeEach, afterAll } from "vitest";
import fs from "fs";
const createTestFile = (size: number) => Buffer.alloc(size);
let testEnv: RulesTestEnvironment;
beforeAll(async () => {
testEnv = await initializeTestEnvironment({
projectId: "stst-et-interviewer-dev",
hub: {
host: "localhost",
port: 4400,
},
});
});
beforeEach(async () => {
await testEnv.clearStorage();
await testEnv.clearFirestore();
});
afterAll(async () => await testEnv.cleanup());
const loadStepStoneImage = () =>
fs.readFileSync("./public/images/stepstoneLogo.svg");
test("Storage does not allow you to read files", async () => {
const rouge = testEnv.unauthenticatedContext();
const alice = testEnv.authenticatedContext("alice");
await assertFails(
rouge.storage().ref("audio/test-interview.flac").getDownloadURL()
);
await assertFails(
alice.storage().ref("audio/test-interview.flac").getDownloadURL()
);
await assertFails(alice.storage().ref("audio/").listAll());
});
test("Storage does not allow you to upload a file if you are not logged in", async () => {
const rouge = testEnv.unauthenticatedContext();
const upload = rouge
.storage("stst-et-interviewer-dev.appspot.com")
.ref("audio/logo.svg")
.put(createTestFile(200), { contentType: "audio/flac" });
await assertFails(upload.then()); // <- GETS STUCK HERE
console.log("this does not happen");
});
What are the possible reasons for this happening? Are there any simple ways of debugging?