HMR is not working for web workers

Bug report

What is the current behavior?

When updating the code loaded by web worker nothing happens.

If the current behavior is a bug, please provide the steps to reproduce.

This is a very simple configuration where HMR doesn’t work: https://github.com/wclr/webpack-worker-hot-reload

What is the expected behavior?

I believe it should work the following way:

1. If the worker’s entry script accepts hot reload, hot reload should be executed in the context of running web worker(s).
2. Otherwise it should be upstreamed to the parent context (probably parent script where new URL of the worker script was created).

Other relevant information: webpack version: 5 Node.js version: 14 Operating System: Additional tools:

[donalffons]

if you want to help feel free to send a PR

Will do!

[alexander-akait]

Here is a simple example that reproduces the error I had: ocjsx-hello-world-webpack-issue.zip @alexander-akait

Yep, bug, we should fix it, if you want to help feel free to send a PR

I’m not sure what would be the best way of doing that - maybe by writing some sort of Webpack Plugin?

Yep, a good question, ideally you need to pass path to worker as argument (you will faced with the same problem not only for webpack, for any other bundlers), multi compiler mode can be useful here too