Issues with using a websocket k6 typescript enum type

[joffotron]

Brief summary

Using e.g. the EventName.Open type from the k6/experimental/websockets compiles but can't be run

k6 version

k6 v0.56.0 (go1.23.4, darwin/arm64)

OS

MacOS 15.3

Docker version and image (if applicable)

No response

Steps to reproduce the problem

I have some code that can be summarised thus:

import { EventName, Params, WebSocket } from 'k6/experimental/websockets';
...

const ws = new WebSocket(`${websocketHost}/ocpp/1.6/`, null, params);
ws.addEventListener(EventName.Open, () => {
    console.log('Connected');
}

I can try running it in several ways:

• k6 run --compatibility-mode=experimental_enhanced src/idle-station.ts
• k6pack src/idle-station.ts| k6 run -
• find ./src -type f -name '*.ts' -exec esbuild '{}' --bundle --outbase=src --outdir=dist --external:k6 --format=esm \; then k6 run dist/idle-station.js

Expected behaviour

I expect the code to compile and run the test

Actual behaviour

For all of the above methods, I get this runtime error:

ERRO[0000] TypeError: Cannot read property 'Open' of undefined
        at idle_station_default (file:///Users/joff/src/chargefox/load-testing/dist/idle-station.js:16:33(19))  executor=shared-iterations scenario=default source=stacktrace

To work around this in the meantime -

I can either use the "open" literal in place of the enum:

ws.addEventListener('open', () => {

Although then my IDE complains of TS2345: Argument of type "open" is not assignable to parameter of type EventName

Or I can use a type assertion:

ws.addEventListener(<EventName>'open', () => {

Which isn't ideal either

[Fernando-hub527]

Hi, I'm starting to contribute to K6 and would like to help with this issue.