Parent.svelte

<script>
let results = [];
$: console.log({ results });
</script>


{#if results.length > 0}
	<Results {results} />
{:else}
	<Search {results} />
{/if}

Search.svelte

<script>
  export let results;

  
  const handleSubmit = () => {
		const requests = artists
			.split('\n')
			.map((a) => a.split(','))
			.flat()
			.map((a) => a.split('b2b'))
			.flat()
			.map((a) => a.trim());
		Promise.allSettled(requests.map((artist) => spotify.searchArtists(artist)))
			.then((promises) => {
				promises.forEach((promise, index) => {
					if (promise.status === 'fulfilled') {
						const { value } = promise;

						if (value.artists.total > 0) {
							results = [...results, value.artists.items[0]];
						}
						return promise.value.artists.items[0];
					}
				});
			})
			.catch((error) => console.log(error));
	};
</script>