From 2fbac34fe9bc479c16ee9537a3cae67aeac61c05 Mon Sep 17 00:00:00 2001
From: AdamW <adam@sidos.com>
Date: Fri, 1 Nov 2024 15:36:43 +0200
Subject: [PATCH] fix(utils): make 'unwrap' update immediate after resolve

---
 src/vanilla/utils/unwrap.ts        | 16 ++++++++++------
 tests/vanilla/utils/unwrap.test.ts | 12 ++++++++++++
 2 files changed, 22 insertions(+), 6 deletions(-)

diff --git a/src/vanilla/utils/unwrap.ts b/src/vanilla/utils/unwrap.ts
index 3313980171..2504f68d51 100644
--- a/src/vanilla/utils/unwrap.ts
+++ b/src/vanilla/utils/unwrap.ts
@@ -60,12 +60,16 @@ export function unwrap<Value, Args extends unknown[], Result, PendingValue>(
             return { v: promise as Awaited<Value> }
           }
           if (promise !== prev?.p) {
-            promise
-              .then(
-                (v) => promiseResultCache.set(promise, v as Awaited<Value>),
-                (e) => promiseErrorCache.set(promise, e),
-              )
-              .finally(setSelf)
+            promise.then(
+              (v) => {
+                promiseResultCache.set(promise, v as Awaited<Value>)
+                setSelf()
+              },
+              (e) => {
+                promiseErrorCache.set(promise, e)
+                setSelf()
+              },
+            )
           }
           if (promiseErrorCache.has(promise)) {
             throw promiseErrorCache.get(promise)
diff --git a/tests/vanilla/utils/unwrap.test.ts b/tests/vanilla/utils/unwrap.test.ts
index a0ca0ed8f5..be294dde54 100644
--- a/tests/vanilla/utils/unwrap.test.ts
+++ b/tests/vanilla/utils/unwrap.test.ts
@@ -137,4 +137,16 @@ describe('unwrap', () => {
     await new Promise((r) => setTimeout(r)) // wait for a tick
     expect(store.get(unwrap(asyncAtom))).toEqual('concrete')
   })
+
+  it('should get a fulfilled value after the promise resolves', async () => {
+    const store = createStore()
+    const asyncAtom = atom(Promise.resolve('concrete'))
+    const syncAtom = unwrap(asyncAtom)
+
+    expect(store.get(syncAtom)).toEqual(undefined)
+
+    await store.get(asyncAtom)
+
+    expect(store.get(syncAtom)).toEqual('concrete')
+  })
 })