fix(utils): atomWithStorage should deal with no localStorage (#951)

Author: dai-shi

src/utils/atomWithStorage.ts

@@ -55,10 +55,14 @@ export function createJSONStorage<Value>(
 export function createJSONStorage<Value>(
   getStringStorage: () => AsyncStringStorage | SyncStringStorage
 ): AsyncStorage<Value> | SyncStorage<Value> {
-  if (!getStringStorage().removeItem) {
-    console.warn(
-      'Missing removeItem. In the next version, it will be required.'
-    )
+  try {
+    if (!getStringStorage().removeItem) {
+      console.warn(
+        'Missing removeItem. In the next version, it will be required.'
+      )
+    }
+  } catch {
+    // getStringStorage can throw if localStorage is not defined
   }
   return {
     getItem: (key) => {

tests/utils/atomWithStorage.test.tsx

@@ -1,7 +1,12 @@
 import { Suspense } from 'react'
 import { fireEvent, render, waitFor } from '@testing-library/react'
 import { useAtom } from 'jotai'
-import { RESET, atomWithHash, atomWithStorage } from 'jotai/utils'
+import {
+  RESET,
+  atomWithHash,
+  atomWithStorage,
+  createJSONStorage,
+} from 'jotai/utils'
 import { getTestProvider } from '../testUtils'
 
 const Provider = getTestProvider()
@@ -180,6 +185,36 @@ describe('atomWithStorage (async)', () => {
   })
 })
 
+describe('atomWithStorage (no storage) (#949)', () => {
+  it('can throw in createJSONStorage', async () => {
+    const countAtom = atomWithStorage(
+      'count',
+      1,
+      createJSONStorage(() => {
+        throw new Error('no storage')
+      })
+    )
+
+    const Counter = () => {
+      const [count, setCount] = useAtom(countAtom)
+      return (
+        <>
+          <div>count: {count}</div>
+          <button onClick={() => setCount((c) => c + 1)}>button</button>
+        </>
+      )
+    }
+
+    const { findByText } = render(
+      <Provider>
+        <Counter />
+      </Provider>
+    )
+
+    await findByText('count: 1')
+  })
+})
+
 describe('atomWithHash', () => {
   it('simple count', async () => {
     const countAtom = atomWithHash('count', 1)