event.prepend(...) doesn't work with undefined

[goodmind]

Code to reproduce the issue:

import { createEvent } from 'effector'

const click = createEvent()
click.watch(console.log)

const preclick = click.prepend(n => n)

preclick()

Expected behavior:

undefined in console

Actual behavior:

click.watch doesn't get called

Versions of packages used:

0.18.1

[gitpod-io-legacy-app]

Open in Gitpod - starts a development workspace with a preconfigured issue branch and opens it in a browser IDE.

[zerobias]

fixed in ba29b8b