fix: handle object browser field (#511)

* fix: handle object browser field

* whoops

* Add changeset

---------

Co-authored-by: Puru Vijay <[email protected]>

Author: gtm-nayan

.changeset/slow-buckets-double.md

@@ -0,0 +1,5 @@
+---
+'@sveltejs/repl': patch
+---
+
+(fix) Make mapbox work by properly resolving fields

packages/repl/src/lib/workers/bundler/index.js

@@ -185,10 +185,21 @@ async function resolve_from_pkg(pkg, subpath, uid, pkg_url_base) {
 
 	// legacy
 	if (subpath === '.') {
-		const resolved_id = resolve.legacy(pkg, {
+		let resolved_id = resolve.legacy(pkg, {
 			fields: ['browser', 'module', 'main']
 		});
 
+		if (typeof resolved_id === 'object' && !Array.isArray(resolved_id)) {
+			const subpath = resolved_id['.'];
+			if (subpath === false) return 'data:text/javascript,export {}';
+
+			resolved_id =
+				subpath ??
+				resolve.legacy(pkg, {
+					fields: ['module', 'main']
+				});
+		}
+
 		if (!resolved_id) {
 			// last ditch — try to match index.js/index.mjs
 			for (const index_file of ['index.mjs', 'index.js']) {