lint

packages/svelte/src/compiler/phases/2-analyze/visitors/AwaitExpression.js

@@ -26,7 +26,7 @@ export function AwaitExpression(node, context) {
 			// @ts-expect-error we could probably use a neater/more robust mechanism
 			if (parent.metadata) break;
 
-			// TODO make this more accurate — we don't need to call suspend
+			// TODO make this more accurate — we don't need to call suspend
 			// if this is the last thing that could be read
 			preserve_context = true;
 		}

packages/svelte/src/internal/client/dom/blocks/each.js

@@ -283,7 +283,7 @@ export function each(node, flags, get_collection, get_key, render_fn, fallback_f
 							update_item(existing, value, i, flags);
 						}
 					} else {
-						var item = create_item(
+						item = create_item(
 							null,
 							state,
 							null,

packages/svelte/src/internal/client/reactivity/batch.js

@@ -130,14 +130,17 @@ export class Batch {
 		batches.delete(this);
 
 		for (var batch of batches) {
+			/** @type {Source} */
+			var source;
+
 			if (batch.#id < this.#id) {
 				// other batch is older than this
-				for (var source of this.#previous.keys()) {
+				for (source of this.#previous.keys()) {
 					batch.#previous.delete(source);
 				}
 			} else {
 				// other batch is newer than this
-				for (var source of batch.#previous.keys()) {
+				for (source of batch.#previous.keys()) {
 					if (this.#previous.has(source)) {
 						batch.#previous.set(source, source.v);
 					}

packages/svelte/src/internal/client/reactivity/deriveds.js

@@ -89,7 +89,7 @@ export function derived(fn) {
 
 /**
  * @template V
- * @param {() => Promise<V>} fn
+ * @param {() => V | Promise<V>} fn
  * @param {string} [location] If provided, print a warning if the value is not read immediately after update
  * @returns {Promise<Source<V>>}
  */
@@ -173,12 +173,21 @@ export function async_derived(fn, location) {
 		);
 	}, EFFECT_ASYNC | EFFECT_PRESERVED);
 
-	return new Promise(async (fulfil) => {
+	return new Promise((fulfil) => {
+		/** @param {Promise<V>} p */
+		function next(p) {
+			p.then(() => {
+				if (p === promise) {
+					fulfil(signal);
+				} else {
 					// if the effect re-runs before the initial promise
 					// resolves, delay resolution until we have a value
-		var p;
+					next(promise);
-		while (p !== (p = promise)) await p;
+				}
-		fulfil(signal);
+			});
+		}
+
+		next(promise);
 	});
 }