feat(computed): add isComputed helper

posva · posva · commit 3b9c1432a714 · 2021-07-21T12:56:15.000+02:00
diff --git a/packages/reactivity/__tests__/deferredComputed.spec.ts b/packages/reactivity/__tests__/deferredComputed.spec.ts
@@ -1,4 +1,12 @@
-import { computed, deferredComputed, effect, ref } from '../src'
+import {
+  computed,
+  deferredComputed,
+  effect,
+  isComputed,
+  reactive,
+  ref,
+  toRaw
+} from '../src'
 
 describe('deferred computed', () => {
   const tick = Promise.resolve()
@@ -182,4 +190,13 @@ describe('deferred computed', () => {
     await tick
     expect(c1Spy).toHaveBeenCalledTimes(1)
   })
+
+  it('isComputed', () => {
+    expect(isComputed(computed(() => 1))).toBe(true)
+    expect(isComputed(deferredComputed(() => 1))).toBe(true)
+    expect(isComputed(ref(1))).toBe(false)
+    expect(isComputed(reactive({}))).toBe(false)
+    expect(isComputed(reactive({ c: computed(() => 1) }).c)).toBe(false)
+    expect(isComputed(toRaw(reactive({ c: computed(() => 1) })).c)).toBe(true)
+  })
 })
diff --git a/packages/reactivity/src/computed.ts b/packages/reactivity/src/computed.ts
@@ -20,7 +20,7 @@ export interface WritableComputedOptions<T> {
   set: ComputedSetter<T>
 }
 
-class ComputedRefImpl<T> {
+export class ComputedRefImpl<T> {
   public dep?: Dep = undefined
 
   private _value!: T
diff --git a/packages/reactivity/src/deferredComputed.ts b/packages/reactivity/src/deferredComputed.ts
@@ -1,6 +1,6 @@
 import { Dep } from './dep'
 import { ReactiveEffect } from './effect'
-import { ComputedGetter, ComputedRef } from './computed'
+import { ComputedGetter, ComputedRef, ComputedRefImpl } from './computed'
 import { ReactiveFlags, toRaw } from './reactive'
 import { trackRefValue, triggerRefValue } from './ref'
 
@@ -24,6 +24,15 @@ const flush = () => {
   queued = false
 }
 
+export function isComputed<T>(
+  value: ComputedRef<T> | unknown
+): value is ComputedRef<T>
+export function isComputed(value: any): value is ComputedRef {
+  return (
+    value instanceof ComputedRefImpl || value instanceof DeferredComputedRefImpl
+  )
+}
+
 class DeferredComputedRefImpl<T> {
   public dep?: Dep = undefined
 
diff --git a/packages/reactivity/src/index.ts b/packages/reactivity/src/index.ts
@@ -36,7 +36,7 @@ export {
   ComputedGetter,
   ComputedSetter
 } from './computed'
-export { deferredComputed } from './deferredComputed'
+export { deferredComputed, isComputed } from './deferredComputed'
 export {
   effect,
   stop,

Original file line number	Diff line number	Diff line change
`@@ -20,7 +20,7 @@ export interface WritableComputedOptions<T> {`
`20`	`20`	`set: ComputedSetter<T>`
`21`	`21`	`}`
`22`	`22`
`23`		`-class ComputedRefImpl<T> {`
	`23`	`+export class ComputedRefImpl<T> {`
`24`	`24`	`public dep?: Dep = undefined`
`25`	`25`
`26`	`26`	`private _value!: T`