fix(reactivity): account for NaN in value change checks (#361)

packages/reactivity/__tests__/collections/Map.spec.ts

@@ -311,5 +311,13 @@ describe('reactivity/collections', () => {
       map.get(key)!.foo++
       expect(dummy).toBe(2)
     })
+
+    it('should not be trigger when the value and the old value both are NaN', () => {
+      const map = reactive(new Map([['foo', NaN]]))
+      const mapSpy = jest.fn(() => map.get('foo'))
+      effect(mapSpy)
+      map.set('foo', NaN)
+      expect(mapSpy).toHaveBeenCalledTimes(1)
+    })
   })
 })

packages/reactivity/__tests__/collections/WeakMap.spec.ts

@@ -107,5 +107,15 @@ describe('reactivity/collections', () => {
       observed.get(key).a = 2
       expect(dummy).toBe(2)
     })
+
+    it('should not be trigger when the value and the old value both are NaN', () => {
+      const map = new WeakMap()
+      const key = {}
+      map.set(key, NaN)
+      const mapSpy = jest.fn(() => map.get(key))
+      effect(mapSpy)
+      map.set(key, NaN)
+      expect(mapSpy).toHaveBeenCalledTimes(1)
+    })
   })
 })

packages/reactivity/__tests__/effect.spec.ts

@@ -691,4 +691,14 @@ describe('reactivity/effect', () => {
     obj.foo = { prop: 1 }
     expect(dummy).toBe(1)
   })
+
+  it('should not be trigger when the value and the old value both are NaN', () => {
+    const obj = reactive({
+      foo: NaN
+    })
+    const fnSpy = jest.fn(() => obj.foo)
+    effect(fnSpy)
+    obj.foo = NaN
+    expect(fnSpy).toHaveBeenCalledTimes(1)
+  })
 })