fix: derived atom is not recomputed after its dependencies changed #2906 (#2907)

* add failing test

* a single recomputeDependents in flushBatch

* centralize finishRecompute

* cleanup

* fix test

* simplify test

* remove redundant changedAtoms set

* mark original atom changed

* flushBatch while condition includes dependents size

* refactor: pass recompute as arg to flushBatch

* rename getMountedDependents and simplify

* remove unnecessary delete dirtybit

* add single recomputeDependents to batch

---------

Co-authored-by: daishi <[email protected]>

Author: dmaskasky

tests/vanilla/store.test.tsx

@@ -1123,6 +1123,24 @@ it('recomputes dependents of unmounted atoms', () => {
   expect(bRead).not.toHaveBeenCalled()
 })
 
+it('recomputes all changed atom dependents together', async () => {
+  const a = atom([0])
+  const b = atom([0])
+  const a0 = atom((get) => get(a)[0]!)
+  const b0 = atom((get) => get(b)[0]!)
+  const a0b0 = atom((get) => [get(a0), get(b0)])
+  const w = atom(null, (_, set) => {
+    set(a, [0])
+    set(b, [1])
+  })
+  const store = createStore()
+  store.sub(a0b0, () => {})
+  store.set(w)
+  expect(store.get(a0)).toBe(0)
+  expect(store.get(b0)).toBe(1)
+  expect(store.get(a0b0)).toEqual([0, 1])
+})
+
 it('should not inf on subscribe or unsubscribe', async () => {
   const store = createStore()
   const countAtom = atom(0)