fix(reactive): avoid chain reactions missing

Author: voderl

packages/reactive/src/__tests__/autorun.spec.ts

@@ -757,3 +757,207 @@ test('avoid unnecessary reaction', () => {
 
   expect(fn1).toBeCalledTimes(1)
 })
+
+test('avoid missing reaction', () => {
+  const obs = observable<any>({
+    res: 0,
+  })
+
+  const fn1 = jest.fn()
+  const fn2 = jest.fn()
+
+  let value
+  autorun(() => {
+    fn1()
+    value = obs.res
+  })
+
+  autorun(() => {
+    fn2()
+    obs.res
+    if (obs.res !== 0) obs.res = obs.res + 1
+  })
+
+  expect(value).toBe(0)
+
+  obs.res = 1
+
+  expect(value).toBe(2)
+
+  expect(fn1).toBeCalledTimes(3)
+  expect(fn2).toBeCalledTimes(2)
+})
+
+test('avoid reaction twice', () => {
+  const obs = observable<any>({
+    res: 0,
+  })
+
+  const fn1 = jest.fn()
+  const fn2 = jest.fn()
+
+  let value
+  autorun(() => {
+    fn1()
+    obs.res
+    if (obs.res !== 0) obs.res = obs.res + 1
+  })
+
+  autorun(() => {
+    fn2()
+    value = obs.res
+  })
+
+  expect(value).toBe(0)
+
+  obs.res = 1
+
+  expect(value).toBe(2)
+  expect(fn1).toBeCalledTimes(2)
+  expect(fn2).toBeCalledTimes(2)
+})
+
+test('computed reaction', () => {
+  const obs = observable<any>({
+    aa: 1,
+    bb: 1,
+  })
+
+  const computed = observable.computed(() => {
+    return obs.aa + obs.bb
+  })
+
+  autorun(() => {
+    if (obs.bb === 3) {
+      obs.aa = 3
+    }
+  })
+
+  batch(() => {
+    obs.aa = 2 // 会触发 computed 发生变化
+
+    obs.bb = 3
+  })
+
+  expect(computed.value).toBe(6)
+})
+
+test('accurate boundary', () => {
+  const obs = observable<any>({
+    a: '',
+    b: '',
+    c: '',
+  })
+
+  autorun(() => {
+    obs.c = obs.a + obs.b
+  })
+
+  autorun(() => {
+    obs.b = obs.a
+  })
+
+  obs.a = 'a'
+  expect(obs.a).toBe('a')
+  expect(obs.b).toBe('a')
+  expect(obs.c).toBe('aa')
+})
+
+test('multiple source update', () => {
+  const obs = observable<any>({})
+
+  const fn1 = jest.fn()
+  const fn2 = jest.fn()
+
+  autorun(() => {
+    const A = obs.A
+    const B = obs.B
+    if (A !== undefined && B !== undefined) {
+      obs.C = A / B
+      fn1()
+    }
+  })
+
+  autorun(() => {
+    const C = obs.C
+    const B = obs.B
+    if (C !== undefined && B !== undefined) {
+      obs.D = C * B
+      fn2()
+    }
+  })
+
+  obs.A = 1
+  obs.B = 2
+
+  expect(fn1).toBeCalledTimes(1)
+  expect(fn2).toBeCalledTimes(1)
+})
+
+test('same source in nest update', () => {
+  const obs = observable<any>({})
+
+  const fn1 = jest.fn()
+
+  autorun(() => {
+    const B = obs.B
+    obs.B = 'B'
+    fn1()
+    return B
+  })
+
+  obs.B = 'B2'
+
+  expect(fn1).toBeCalledTimes(2)
+})
+
+test('batch execute autorun cause by deep indirect dependency', () => {
+  const obs: any = observable({ aa: 1, bb: 1, cc: 1 })
+  const fn = jest.fn()
+  const fn2 = jest.fn()
+  const fn3 = jest.fn()
+
+  autorun(() => fn((obs.aa = obs.bb + obs.cc)))
+  autorun(() => fn2((obs.bb = obs.aa + obs.cc)))
+  autorun(() => fn3((obs.cc = obs.aa + obs.bb)))
+
+  // 嵌套写法重复调用没意义，只需要确保最新被触发的 reaction 执行，已过时的 reaction 可以忽略
+  // 比如 fn3 执行，触发 fn 和 fn2，fn 执行又触发 fn2，之前触发的 fn2 是过时的，忽略处理，fn2 只执行一次
+  expect(fn).toBeCalledTimes(3)
+  expect(fn2).toBeCalledTimes(2)
+  expect(fn3).toBeCalledTimes(1)
+
+  fn.mockClear()
+  fn2.mockClear()
+  fn3.mockClear()
+
+  batch(() => {
+    obs.aa = 100
+    obs.bb = 100
+    obs.cc = 100
+  })
+
+  expect(fn).toBeCalledTimes(1)
+  expect(fn2).toBeCalledTimes(1)
+  expect(fn3).toBeCalledTimes(1)
+})
+
+test('multiple update should trigger only one', () => {
+  const obs = observable({ aa: 1, bb: 1 })
+
+  autorun(() => {
+    obs.aa = obs.bb + 1
+    obs.bb = obs.aa + 1
+  })
+
+  expect(obs.aa).toBe(2)
+  expect(obs.bb).toBe(3)
+
+  autorun(() => {
+    obs.aa = obs.bb + 1
+    obs.bb = obs.aa + 1
+  })
+
+  expect(obs.aa).toBe(6)
+  expect(obs.bb).toBe(7)
+})

packages/reactive/src/__tests__/tracker.spec.ts

@@ -89,5 +89,5 @@ test('shared scheduler with multi tracker(mock react strict mode)', () => {
   obs.value = 123
 
   expect(scheduler1).toBeCalledTimes(1)
-  expect(scheduler2).toBeCalledTimes(0)
+  expect(scheduler2).toBeCalledTimes(1)
 })

packages/reactive/src/array.ts

@@ -49,12 +49,15 @@ export class ArraySet<T> {
 
   batchDelete(callback: (value: T) => void) {
     if (this.value.length === 0) return
-    this.forEachIndex = 0
-    for (; this.forEachIndex < this.value.length; this.forEachIndex++) {
-      const value = this.value[this.forEachIndex]
-      this.value.splice(this.forEachIndex, 1)
-      this.forEachIndex--
-      callback(value)
+
+    const batchList = this.value.splice(0, this.value.length)
+
+    for (let i = 0; i < batchList.length; i++) {
+      callback(batchList[i])
+    }
+
+    if (this.value.length > 0) {
+      this.batchDelete(callback)
     }
   }
 

packages/reactive/src/environment.ts

@@ -11,6 +11,7 @@ export const RawReactionsMap = new WeakMap<object, ReactionsMap>()
 export const ReactionStack: Reaction[] = []
 export const BatchCount = { value: 0 }
 export const UntrackCount = { value: 0 }
+export const BatchIdRef = { current: 1 }
 export const BatchScope = { value: false }
 export const DependencyCollected = { value: false }
 export const PendingReactions = new ArraySet<Reaction>()

packages/reactive/src/reaction.ts

@@ -14,6 +14,7 @@ import {
   ObserverListeners,
   PendingComputedReactions,
   PendingScopeComputedReactions,
+  BatchIdRef,
 } from './environment'
 
 const ITERATION_KEY = Symbol('iteration key')
@@ -221,13 +222,7 @@ export const batchScopeEnd = () => {
   })
 
   BatchScope.value = false
-  PendingScopeReactions.batchDelete((reaction) => {
-    if (isFn(reaction._scheduler)) {
-      reaction._scheduler(reaction)
-    } else {
-      reaction()
-    }
-  })
+  executePendingScopeReactions()
   UntrackCount.value = prevUntrackCount
 }
 
@@ -254,11 +249,29 @@ export const executePendingComputedReactions = () => {
 }
 
 export const executePendingReactions = () => {
+  const batchId = BatchIdRef.current++
   PendingReactions.batchDelete((reaction) => {
-    if (isFn(reaction._scheduler)) {
-      reaction._scheduler(reaction)
-    } else {
-      reaction()
+    if (batchId > (reaction._batchId || 0)) {
+      reaction._batchId = batchId
+      if (isFn(reaction._scheduler)) {
+        reaction._scheduler(reaction)
+      } else {
+        reaction()
+      }
+    }
+  })
+}
+
+export const executePendingScopeReactions = () => {
+  const batchId = BatchIdRef.current++
+  PendingScopeReactions.batchDelete((reaction) => {
+    if (batchId > (reaction._batchId || 0)) {
+      reaction._batchId = batchId
+      if (isFn(reaction._scheduler)) {
+        reaction._scheduler(reaction)
+      } else {
+        reaction()
+      }
     }
   })
 }

packages/reactive/src/types.ts

@@ -70,6 +70,7 @@ export type Reaction = ((...args: any[]) => any) & {
   _property?: PropertyKey
   _computesSet?: ArraySet<Reaction>
   _reactionsSet?: ArraySet<ReactionsMap>
+  _batchId?: number
   _scheduler?: (reaction: Reaction) => void
   _memos?: {
     queue: IMemoQueueItem[]