.github/ISSUE_TEMPLATE/bug_report.md

@@ -19,7 +19,7 @@ assignees: ''
 
 Please do not ask questions in issues.
 
-- [ ] I understand this is not a question.
+- [ ] I've already opened a [discussion](https://github.com/pmndrs/jotai/discussions) before opening this issue.
 
 Please include a minimal reproduction.
 

.github/workflows/test-old-typescript.yml

@@ -52,7 +52,7 @@ jobs:
           sed -i~ "s/^.* from '\.\/utils\/waitForAll';//" dist/ts3.4/utils.d.ts
           yarn json -I -f package.json -e "this.resolutions={}; this.resolutions['@types/jest']='26.0.14'; this.resolutions['pretty-format']='25.5.0'; this.resolutions['@types/prettier']='2.4.2';"
           yarn add -D @types/jest@26.0.14 pretty-format@25.5.0 @types/prettier@2.4.2 @types/yargs@17.0.13 @types/babel__traverse@7.18.2
-          rm -r tests/utils/atomWithObservable.* tests/utils/waitForAll.* tests/vanilla/utils/atomWithObservable.*
+          rm -r tests/utils/atomWithObservable.* tests/utils/waitForAll.* tests/react/vanilla-utils/atomWithObservable.*
       - name: Ignore Async API tests for Older TS
         if: ${{ matrix.typescript == '3.7.5' }}
         run: |

package.json

@@ -1,7 +1,7 @@
 {
   "name": "jotai",
   "private": true,
-  "version": "1.12.0",
+  "version": "1.12.1",
   "description": "👻 Next gen state management that will spook you",
   "main": "./index.js",
   "types": "./index.d.ts",
@@ -141,31 +141,31 @@
     ]
   },
   "devDependencies": {
-    "@babel/core": "^7.20.5",
-    "@babel/plugin-transform-react-jsx": "^7.19.0",
-    "@babel/plugin-transform-typescript": "^7.20.2",
+    "@babel/core": "^7.20.7",
+    "@babel/plugin-transform-react-jsx": "^7.20.7",
+    "@babel/plugin-transform-typescript": "^7.20.7",
     "@babel/preset-env": "^7.20.2",
-    "@babel/template": "^7.18.10",
-    "@babel/types": "^7.20.5",
+    "@babel/template": "^7.20.7",
+    "@babel/types": "^7.20.7",
     "@redux-devtools/extension": "^3.2.3",
     "@rollup/plugin-babel": "^6.0.3",
     "@rollup/plugin-node-resolve": "^15.0.1",
     "@rollup/plugin-replace": "^5.0.2",
     "@rollup/plugin-typescript": "^10.0.1",
-    "@swc/core": "^1.3.23",
+    "@swc/core": "^1.3.24",
     "@swc/jest": "^0.2.24",
     "@tanstack/query-core": "^4.20.4",
     "@testing-library/react": "^13.4.0",
     "@types/jest": "^29.2.4",
     "@types/react": "^18.0.26",
-    "@types/react-dom": "^18.0.9",
-    "@typescript-eslint/eslint-plugin": "^5.47.0",
-    "@typescript-eslint/parser": "^5.47.0",
+    "@types/react-dom": "^18.0.10",
+    "@typescript-eslint/eslint-plugin": "^5.47.1",
+    "@typescript-eslint/parser": "^5.47.1",
     "@urql/core": "^3.1.1",
     "benny": "^3.7.1",
     "concurrently": "^7.6.0",
     "downlevel-dts": "^0.11.0",
-    "esbuild": "^0.16.10",
+    "esbuild": "^0.16.12",
     "eslint": "^8.30.0",
     "eslint-config-prettier": "^8.5.0",
     "eslint-import-resolver-alias": "^1.1.2",
@@ -193,7 +193,7 @@
     "react": "^18.2.0",
     "react-dom": "^18.2.0",
     "redux": "^4.2.0",
-    "rollup": "^3.7.5",
+    "rollup": "^3.9.0",
     "rollup-plugin-esbuild": "^5.0.0",
     "rollup-plugin-terser": "^7.0.2",
     "rxjs": "^7.8.0",
@@ -202,7 +202,7 @@
     "ts-node": "^10.9.1",
     "tslib": "^2.4.1",
     "typescript": "^4.9.4",
-    "valtio": "^1.7.6",
+    "valtio": "^1.8.0",
     "wonka": "^6.1.2",
     "xstate": "^4.35.1",
     "zustand": "^4.1.5"

src/vanilla/store.ts

@@ -528,7 +528,21 @@ export const createStore = () => {
             mountDependencies(atom, atomState, prevAtomState?.d)
           }
           const mounted = mountedMap.get(atom)
-          mounted?.l.forEach((listener) => listener())
+          if (
+            mounted &&
+            !(
+              // TODO This seems pretty hacky. Hope to fix it.
+              // Maybe we could `mountDependencies` in `setAtomState`?
+              (
+                prevAtomState &&
+                !hasPromiseAtomValue(prevAtomState) &&
+                (isEqualAtomValue(prevAtomState, atomState) ||
+                  isEqualAtomError(prevAtomState, atomState))
+              )
+            )
+          ) {
+            mounted.l.forEach((listener) => listener())
+          }
         } else if (__DEV__) {
           console.warn('[Bug] no atom state to flush')
         }
@@ -541,9 +555,9 @@ export const createStore = () => {
 
   const subscribeAtom = (atom: AnyAtom, listener: () => void) => {
     const mounted = addAtom(atom)
+    flushPending()
     const listeners = mounted.l
     listeners.add(listener)
-    flushPending()
     return () => {
       listeners.delete(listener)
       delAtom(atom)

tests/vanilla/store.test.tsx

@@ -0,0 +1,33 @@
+import { atom, createStore } from 'jotai/vanilla'
+
+it('should not fire on subscribe', async () => {
+  const store = createStore()
+  const countAtom = atom(0)
+  const callback1 = jest.fn()
+  const callback2 = jest.fn()
+  store.sub(countAtom, callback1)
+  store.sub(countAtom, callback2)
+  expect(callback1).not.toBeCalled()
+  expect(callback2).not.toBeCalled()
+})
+
+it('should not fire subscription if primitive atom value is the same', async () => {
+  const store = createStore()
+  const countAtom = atom(0)
+  const callback = jest.fn()
+  store.sub(countAtom, callback)
+  const calledTimes = callback.mock.calls.length
+  store.set(countAtom, 0)
+  expect(callback).toBeCalledTimes(calledTimes)
+})
+
+it('should not fire subscription if derived atom value is the same', async () => {
+  const store = createStore()
+  const countAtom = atom(0)
+  const derivedAtom = atom((get) => get(countAtom) * 0)
+  const callback = jest.fn()
+  store.sub(derivedAtom, callback)
+  const calledTimes = callback.mock.calls.length
+  store.set(countAtom, 1)
+  expect(callback).toBeCalledTimes(calledTimes)
+})