Feature: useHydrateAtoms

.size-snapshot.json

@@ -1,8 +1,8 @@
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@@ -14,23 +14,23 @@
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@@ -42,9 +42,9 @@
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@@ -56,9 +56,9 @@
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@@ -70,9 +70,9 @@
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@@ -84,9 +84,9 @@
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@@ -98,9 +98,9 @@
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@@ -112,9 +112,9 @@
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@@ -126,9 +126,9 @@
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@@ -140,9 +140,9 @@
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src/core/Provider.ts

@@ -81,7 +81,7 @@ export const subscribeDebugStore = (
 // We keep a reference to the atoms in Provider's registeredAtoms in dev mode,
 // so atoms aren't garbage collected by the WeakMap of mounted atoms
 const useDebugState = (store: StoreForDevelopment) => {
-  const debugMutableSource = store[3]
+  const debugMutableSource = store[4]
   const [state, atoms] = useMutableSource(
     debugMutableSource,
     getDebugStateAndAtoms,

src/core/contexts.ts

@@ -14,7 +14,9 @@ const createStoreForProduction = (
     atom: WritableAtom<Value, Update>,
     update: Update
   ) => writeAtom(state, atom, update)
-  return [stateMutableSource, updateAtom, commitCallback] as const
+  const restore = (values: Iterable<readonly [Atom<unknown>, unknown]>) =>
+    restoreAtoms(state, values)
+  return [stateMutableSource, updateAtom, commitCallback, restore] as const
 }
 
 const createStoreForDevelopment = (
@@ -54,8 +56,8 @@ const createStoreForDevelopment = (
     stateMutableSource,
     updateAtom,
     commitCallback,
-    debugMutableSource,
     restore,
+    debugMutableSource,
   ] as const
 }
 
@@ -84,5 +86,5 @@ export const getStoreContext = (scope?: Scope) => {
 }
 
 export const isDevStore = (store: Store): store is StoreForDevelopment => {
-  return store.length > 3
+  return store.length > 4
 }

src/devtools/useAtomsSnapshot.ts

@@ -12,7 +12,7 @@ type AtomsSnapshot = Map<Atom<unknown>, unknown>
 
 export function useAtomsSnapshot(scope?: Scope): AtomsSnapshot {
   const StoreContext = getStoreContext(scope)
-  const debugMutableSource = useContext(StoreContext)[3]
+  const debugMutableSource = useContext(StoreContext)[4]
 
   if (debugMutableSource === undefined) {
     throw Error('useAtomsSnapshot can only be used in dev mode.')

src/devtools/useGotoAtomsSnapshot.ts

@@ -11,7 +11,7 @@ export function useGotoAtomsSnapshot(scope?: Scope) {
   if (!isDevStore(store)) {
     throw new Error('useGotoAtomsSnapshot can only be used in dev mode.')
   }
-  const restore = store[4]
+  const restore = store[3]
   return useCallback(
     (values: Parameters<typeof restore>[0]) => {
       restore(values)

src/utils.ts

@@ -18,3 +18,4 @@ export {
   createJSONStorage,
 } from './utils/atomWithStorage'
 export { atomWithObservable } from './utils/atomWithObservable'
+export { useHydrateAtoms } from './utils/useHydrateAtoms'

src/utils/useHydrateAtoms.ts

@@ -0,0 +1,37 @@
+import { useContext } from 'react'
+import { SECRET_INTERNAL_getStoreContext as getStoreContext } from 'jotai'
+import type { Atom, Scope } from '../core/atom'
+import type { Store } from '../core/contexts'
+
+const hydratedMap: WeakMap<Store, WeakSet<Atom<unknown>>> = new WeakMap()
+
+export function useHydrateAtoms(
+  values: Iterable<readonly [Atom<unknown>, unknown]>,
+  scope?: Scope
+) {
+  const StoreContext = getStoreContext(scope)
+  const store = useContext(StoreContext)
+  const restoreAtoms = store[3]
+
+  const hydratedSet = getHydratedSet(store)
+  const tuplesToRestore = []
+  for (const tuple of values) {
+    const atom = tuple[0]
+    if (!hydratedSet.has(atom)) {
+      hydratedSet.add(atom)
+      tuplesToRestore.push(tuple)
+    }
+  }
+  if (tuplesToRestore.length) {
+    restoreAtoms(tuplesToRestore)
+  }
+}
+
+function getHydratedSet(store: Store) {
+  let hydratedSet = hydratedMap.get(store)
+  if (!hydratedSet) {
+    hydratedSet = new WeakSet()
+    hydratedMap.set(store, hydratedSet)
+  }
+  return hydratedSet
+}