fix(computedAsync): type signature (#4207)

ferferga · web-flow · commit 45b187a0c85d · 2024-09-12T14:06:17.000Z
Signed-off-by: GitHub &lt;noreply@github.com&gt;
diff --git a/packages/core/computedAsync/index.test.ts b/packages/core/computedAsync/index.test.ts
@@ -1,6 +1,7 @@
+import type { Ref } from 'vue-demi'
 import { computed, nextTick, ref } from 'vue-demi'
 import { promiseTimeout } from '@vueuse/shared'
-import { describe, expect, it, vi } from 'vitest'
+import { describe, expect, expectTypeOf, it, vi } from 'vitest'
 import { asyncComputed, computedAsync } from '.'
 
 describe('computed', () => {
@@ -37,6 +38,16 @@ describe('computedAsync', () => {
     expect(data.value).toBe('data')
   })
 
+  it('types are correct', async () => {
+    const func = vi.fn(() => Promise.resolve('data'))
+
+    const data1 = computedAsync(func)
+    const data2 = computedAsync(func, 'initialState')
+
+    expectTypeOf(data1).toEqualTypeOf<Ref<string | undefined>>()
+    expectTypeOf(data2).toEqualTypeOf<Ref<string>>()
+  })
+
   it('call onError when error is thrown', async () => {
     let errorMessage
     const func = vi.fn(async () => {
@@ -180,7 +191,7 @@ describe('computedAsync', () => {
       return Promise.resolve(result)
     })
     const other = computed(() => {
-      return double.value + 1
+      return (double.value ?? 0) + 1
     })
 
     expect(double.value).toBeUndefined()
diff --git a/packages/core/computedAsync/index.ts b/packages/core/computedAsync/index.ts
@@ -44,11 +44,21 @@ export interface AsyncComputedOptions {
  * @param initialState           The initial state, used until the first evaluation finishes
  * @param optionsOrRef           Additional options or a ref passed to receive the updates of the async evaluation
  */
+export function computedAsync<T>(
+  evaluationCallback: (onCancel: AsyncComputedOnCancel) => T | Promise<T>,
+  initialState: T,
+  optionsOrRef?: Ref<boolean> | AsyncComputedOptions,
+): Ref<T>
+export function computedAsync<T>(
+  evaluationCallback: (onCancel: AsyncComputedOnCancel) => T | Promise<T>,
+  initialState?: undefined,
+  optionsOrRef?: Ref<boolean> | AsyncComputedOptions,
+): Ref<T | undefined>
 export function computedAsync<T>(
   evaluationCallback: (onCancel: AsyncComputedOnCancel) => T | Promise<T>,
   initialState?: T,
   optionsOrRef?: Ref<boolean> | AsyncComputedOptions,
-): Ref<T> {
+): Ref<T> | Ref<T | undefined> {
   let options: AsyncComputedOptions
 
   if (isRef(optionsOrRef)) {
