Bug

The following:

import { onExit } from 'signal-exit'

const cleanup = onExit(() => {
  console.log('A')
  cleanup()
})

onExit(() => {
  console.log('B')
})

Prints:

A

But should print:

A
B

Reason

When the exit is happening, signal-exit is iterating over the exit handlers here:

However, cleanup() ends up calling:

Which directly mutates this.listeners. This makes the iteration above not work anymore, due to mutating an array while iterating on it. Instead, the following would work:

    for (const fn of [...this.listeners[ev]]) {