goToPrev isn't working in unit test environment

[cannahum]

I have a control button that triggers the following:

function handlePrevClick() {
	if (currentPageIndex > 0) {
		carousel.goToPrev();
	}
}

I'm also tracking changes this way:

function handlePageChange(e: CustomEvent<number>) {
	currentPageIndex = e.detail;
}

<Carousel
	arrows={false}
	bind:this={carousel}
	dots={false}
	infinite={false}
	on:pageChange={handlePageChange}
	swiping={false}
>
</Carousel

The issue happens when handlePrevClick is called via a button click. It's working well in browser: I can debug the handlePrevClick and handlePageChange are both called; however, when I run unit tests (testing-library/svelte), even though I can see that handlePrevClick is called, handlePageChange isn't called.