XMLHttpRequest upload (upload.onprogress) event is not supported

[MeetinaXD]

Hi, I noticed that #292 mentioned that interceptor has added support for the upload event of XMLHttpRequest, but I tried to use XHR to upload files in the latest version of msw, and the progress event was not triggered.

By the way, #292 mentions adding support for the progress event, but this only works in response.

I'm wondering if it's possible to add support for the progress event in upload?

---

Environment

• msw: 2.3.0
• nodejs: 2.3.0
• pnpm: 9.0.6

To Reproduce

const xhr = new XMLHttpRequest()

// codes...
xhr.upload.onprogress =({ loaded, total }) => {
    console.log(loaded, total) // not triggered
};

xhr.send(someFormData)