fix(createEventHook): make createEventHook union type can be inferred

vueuse · Nov 28, 2023 · 1609e94 · 1609e94
1 parent 8ba4df8
commit 1609e94
Show file tree

Hide file tree

Showing 2 changed files with 14 additions and 1 deletion.
diff --git a/packages/shared/createEventHook/index.test.ts b/packages/shared/createEventHook/index.test.ts
@@ -93,6 +93,19 @@ describe('createEventHook', () => {
     expect(result).toEqual([2])
   })
 
+  it('should pass union type', () => {
+    let count = 0
+
+    const { on: onResult, trigger } = createEventHook<number | string>()
+
+    // union type should be inferred
+    onResult(value => count = 2)
+    trigger(1)
+    trigger(2)
+
+    expect(count).toBe(2)
+  })
+
   it('the same listener should fire only once', () => {
     const listener = vi.fn()
     const { on, trigger, off } = createEventHook<string>()

diff --git a/packages/shared/createEventHook/index.ts b/packages/shared/createEventHook/index.ts
@@ -4,7 +4,7 @@
  */
 import { tryOnScopeDispose } from '../tryOnScopeDispose'
 
-type Callback<T> = T extends void ? () => void : (param: T) => void
+type Callback<T> = [T] extends [void] ? () => void : (param: T) => void
 export type EventHookOn<T = any> = (fn: Callback<T>) => { off: () => void }
 export type EventHookOff<T = any> = (fn: Callback<T>) => void
 export type EventHookTrigger<T = any> = (param?: T) => Promise<unknown[]>