feat: add once function in emitter

src/use/emitter.js

@@ -58,12 +58,21 @@ export function useEmitter() {
     })
   }
 
+  function once(type, handler) {
+    const handleOn = () => {
+      handler && handler()
+      off(type, handleOn)
+    }
+    on(type, handleOn)
+  }
+
   return {
     on,
     broadcast,
     dispatch,
     off,
-    emit
+    emit,
+    once
   }
 }
 

test/unit/tests/use/emitter.test.js

@@ -1,4 +1,4 @@
-import { useEmitter } from '../../../../src/use/new-emitter'
+import { useEmitter } from '../../../../src/use/emitter'
 import { mount } from '@vue/test-utils'
 import { onMounted } from 'vue'
 
@@ -161,4 +161,23 @@ describe('useEmitter', () => {
 
     expect(handleEmit).toBeCalledTimes(2)
   })
+
+  it('once ', () => {
+    const handleEmit = jest.fn()
+    const Comp = {
+      template: '<div></div>',
+      setup() {
+        const { once, emit } = useEmitter()
+
+        once('emit', handleEmit)
+
+        emit('emit', 1)
+        emit('emit', 2)
+      }
+    }
+
+    mount(Comp)
+
+    expect(handleEmit).toBeCalledTimes(1)
+  })
 })