feat(reactivity): more efficient reactivity system (#5912)

fix #311, fix #1811, fix #6018, fix #7160, fix #8714, fix #9149, fix #9419, fix #9464

Author: johnsoncodehk

packages/reactivity/__tests__/computed.spec.ts

@@ -184,7 +184,7 @@ describe('reactivity/computed', () => {
     // mutate n
     n.value++
     // on the 2nd run, plusOne.value should have already updated.
-    expect(plusOneValues).toMatchObject([1, 2, 2])
+    expect(plusOneValues).toMatchObject([1, 2])
   })
 
   it('should warn if trying to set a readonly computed', () => {
@@ -288,4 +288,167 @@ describe('reactivity/computed', () => {
       oldValue: 2
     })
   })
+
+  // https://github.com/vuejs/core/pull/5912#issuecomment-1497596875
+  it('should query deps dirty sequentially', () => {
+    const cSpy = vi.fn()
+
+    const a = ref<null | { v: number }>({
+      v: 1
+    })
+    const b = computed(() => {
+      return a.value
+    })
+    const c = computed(() => {
+      cSpy()
+      return b.value?.v
+    })
+    const d = computed(() => {
+      if (b.value) {
+        return c.value
+      }
+      return 0
+    })
+
+    d.value
+    a.value!.v = 2
+    a.value = null
+    d.value
+    expect(cSpy).toHaveBeenCalledTimes(1)
+  })
+
+  // https://github.com/vuejs/core/pull/5912#issuecomment-1738257692
+  it('chained computed dirty reallocation after querying dirty', () => {
+    let _msg: string | undefined
+
+    const items = ref<number[]>()
+    const isLoaded = computed(() => {
+      return !!items.value
+    })
+    const msg = computed(() => {
+      if (isLoaded.value) {
+        return 'The items are loaded'
+      } else {
+        return 'The items are not loaded'
+      }
+    })
+
+    effect(() => {
+      _msg = msg.value
+    })
+
+    items.value = [1, 2, 3]
+    items.value = [1, 2, 3]
+    items.value = undefined
+
+    expect(_msg).toBe('The items are not loaded')
+  })
+
+  it('chained computed dirty reallocation after trigger computed getter', () => {
+    let _msg: string | undefined
+
+    const items = ref<number[]>()
+    const isLoaded = computed(() => {
+      return !!items.value
+    })
+    const msg = computed(() => {
+      if (isLoaded.value) {
+        return 'The items are loaded'
+      } else {
+        return 'The items are not loaded'
+      }
+    })
+
+    _msg = msg.value
+    items.value = [1, 2, 3]
+    isLoaded.value // <- trigger computed getter
+    _msg = msg.value
+    items.value = undefined
+    _msg = msg.value
+
+    expect(_msg).toBe('The items are not loaded')
+  })
+
+  // https://github.com/vuejs/core/pull/5912#issuecomment-1739159832
+  it('deps order should be consistent with the last time get value', () => {
+    const cSpy = vi.fn()
+
+    const a = ref(0)
+    const b = computed(() => {
+      return a.value % 3 !== 0
+    })
+    const c = computed(() => {
+      cSpy()
+      if (a.value % 3 === 2) {
+        return 'expensive'
+      }
+      return 'cheap'
+    })
+    const d = computed(() => {
+      return a.value % 3 === 2
+    })
+    const e = computed(() => {
+      if (b.value) {
+        if (d.value) {
+          return 'Avoiding expensive calculation'
+        }
+      }
+      return c.value
+    })
+
+    e.value
+    a.value++
+    e.value
+
+    expect(e.effect.deps.length).toBe(3)
+    expect(e.effect.deps.indexOf((b as any).dep)).toBe(0)
+    expect(e.effect.deps.indexOf((d as any).dep)).toBe(1)
+    expect(e.effect.deps.indexOf((c as any).dep)).toBe(2)
+    expect(cSpy).toHaveBeenCalledTimes(2)
+
+    a.value++
+    e.value
+
+    expect(cSpy).toHaveBeenCalledTimes(2)
+  })
+
+  it('should trigger by the second computed that maybe dirty', () => {
+    const cSpy = vi.fn()
+
+    const src1 = ref(0)
+    const src2 = ref(0)
+    const c1 = computed(() => src1.value)
+    const c2 = computed(() => (src1.value % 2) + src2.value)
+    const c3 = computed(() => {
+      cSpy()
+      c1.value
+      c2.value
+    })
+
+    c3.value
+    src1.value = 2
+    c3.value
+    expect(cSpy).toHaveBeenCalledTimes(2)
+    src2.value = 1
+    c3.value
+    expect(cSpy).toHaveBeenCalledTimes(3)
+  })
+
+  it('should trigger the second effect', () => {
+    const fnSpy = vi.fn()
+    const v = ref(1)
+    const c = computed(() => v.value)
+
+    effect(() => {
+      c.value
+    })
+    effect(() => {
+      c.value
+      fnSpy()
+    })
+
+    expect(fnSpy).toBeCalledTimes(1)
+    v.value = 2
+    expect(fnSpy).toBeCalledTimes(2)
+  })
 })

packages/reactivity/__tests__/deferredComputed.spec.ts

@@ -1,57 +1,32 @@
-import { computed, deferredComputed, effect, ref } from '../src'
+import { computed, effect, ref } from '../src'
 
 describe('deferred computed', () => {
-  const tick = Promise.resolve()
-
-  test('should only trigger once on multiple mutations', async () => {
+  test('should not trigger if value did not change', () => {
     const src = ref(0)
-    const c = deferredComputed(() => src.value)
+    const c = computed(() => src.value % 2)
     const spy = vi.fn()
     effect(() => {
       spy(c.value)
     })
     expect(spy).toHaveBeenCalledTimes(1)
-    src.value = 1
     src.value = 2
-    src.value = 3
-    // not called yet
-    expect(spy).toHaveBeenCalledTimes(1)
-    await tick
-    // should only trigger once
-    expect(spy).toHaveBeenCalledTimes(2)
-    expect(spy).toHaveBeenCalledWith(c.value)
-  })
 
-  test('should not trigger if value did not change', async () => {
-    const src = ref(0)
-    const c = deferredComputed(() => src.value % 2)
-    const spy = vi.fn()
-    effect(() => {
-      spy(c.value)
-    })
-    expect(spy).toHaveBeenCalledTimes(1)
-    src.value = 1
-    src.value = 2
-
-    await tick
     // should not trigger
     expect(spy).toHaveBeenCalledTimes(1)
 
     src.value = 3
-    src.value = 4
     src.value = 5
-    await tick
     // should trigger because latest value changes
     expect(spy).toHaveBeenCalledTimes(2)
   })
 
-  test('chained computed trigger', async () => {
+  test('chained computed trigger', () => {
     const effectSpy = vi.fn()
     const c1Spy = vi.fn()
     const c2Spy = vi.fn()
 
     const src = ref(0)
-    const c1 = deferredComputed(() => {
+    const c1 = computed(() => {
       c1Spy()
       return src.value % 2
     })
@@ -69,19 +44,18 @@ describe('deferred computed', () => {
     expect(effectSpy).toHaveBeenCalledTimes(1)
 
     src.value = 1
-    await tick
     expect(c1Spy).toHaveBeenCalledTimes(2)
     expect(c2Spy).toHaveBeenCalledTimes(2)
     expect(effectSpy).toHaveBeenCalledTimes(2)
   })
 
-  test('chained computed avoid re-compute', async () => {
+  test('chained computed avoid re-compute', () => {
     const effectSpy = vi.fn()
     const c1Spy = vi.fn()
     const c2Spy = vi.fn()
 
     const src = ref(0)
-    const c1 = deferredComputed(() => {
+    const c1 = computed(() => {
       c1Spy()
       return src.value % 2
     })
@@ -98,26 +72,24 @@ describe('deferred computed', () => {
     src.value = 2
     src.value = 4
     src.value = 6
-    await tick
-    // c1 should re-compute once.
-    expect(c1Spy).toHaveBeenCalledTimes(2)
+    expect(c1Spy).toHaveBeenCalledTimes(4)
     // c2 should not have to re-compute because c1 did not change.
     expect(c2Spy).toHaveBeenCalledTimes(1)
     // effect should not trigger because c2 did not change.
     expect(effectSpy).toHaveBeenCalledTimes(1)
   })
 
-  test('chained computed value invalidation', async () => {
+  test('chained computed value invalidation', () => {
     const effectSpy = vi.fn()
     const c1Spy = vi.fn()
     const c2Spy = vi.fn()
 
     const src = ref(0)
-    const c1 = deferredComputed(() => {
+    const c1 = computed(() => {
       c1Spy()
       return src.value % 2
     })
-    const c2 = deferredComputed(() => {
+    const c2 = computed(() => {
       c2Spy()
       return c1.value + 1
     })
@@ -139,17 +111,17 @@ describe('deferred computed', () => {
     expect(c2Spy).toHaveBeenCalledTimes(2)
   })
 
-  test('sync access of invalidated chained computed should not prevent final effect from running', async () => {
+  test('sync access of invalidated chained computed should not prevent final effect from running', () => {
     const effectSpy = vi.fn()
     const c1Spy = vi.fn()
     const c2Spy = vi.fn()
 
     const src = ref(0)
-    const c1 = deferredComputed(() => {
+    const c1 = computed(() => {
       c1Spy()
       return src.value % 2
     })
-    const c2 = deferredComputed(() => {
+    const c2 = computed(() => {
       c2Spy()
       return c1.value + 1
     })
@@ -162,14 +134,13 @@ describe('deferred computed', () => {
     src.value = 1
     // sync access c2
     c2.value
-    await tick
     expect(effectSpy).toHaveBeenCalledTimes(2)
   })
 
-  test('should not compute if deactivated before scheduler is called', async () => {
+  test('should not compute if deactivated before scheduler is called', () => {
     const c1Spy = vi.fn()
     const src = ref(0)
-    const c1 = deferredComputed(() => {
+    const c1 = computed(() => {
       c1Spy()
       return src.value % 2
     })
@@ -179,7 +150,6 @@ describe('deferred computed', () => {
     c1.effect.stop()
     // trigger
     src.value++
-    await tick
     expect(c1Spy).toHaveBeenCalledTimes(1)
   })
 })