fix adding url search params

Author: paoloricciuti

sites/svelte.dev/src/routes/(authed)/repl/+page.js

@@ -1,20 +1,5 @@
 import { redirect } from '@sveltejs/kit';
 
-/**
- * create a query params string from an object of query parameters
- * @param {Record<string, string>} queries
- * @returns {string}
- */
-function add_query_params(queries) {
-	const query_array = [];
-	for (let query in queries) {
-		if (queries[query] !== null) {
-			query_array.push(`${query}=${queries[query]}`);
-		}
-	}
-	return query_array.length > 0 ? `?${query_array.join('&')}` : ``;
-}
-
 export function load({ url }) {
 	const query = url.searchParams;
 	const gist = query.get('gist');
@@ -28,9 +13,12 @@ export function load({ url }) {
 	}
 
 	const id = gist || example || 'hello-world';
-	const q = add_query_params({
-		version,
-		vim
-	});
-	throw redirect(301, `/repl/${id}${q}`);
+	// we need to filter out null values
+	const q = new URLSearchParams(
+		Object.entries({
+			version,
+			vim
+		}).filter(([, value]) => value !== null)
+	).toString();
+	throw redirect(301, `/repl/${id}?${q}`);
 }