Fix/emitted events cache

src/emit.ts

@@ -11,7 +11,7 @@ const enum DevtoolsHooks {
   COMPONENT_EMIT = 'component:emit'
 }
 
-let events: Events
+let events: Events = {}
 
 export function emitted<T = unknown>(
   vm: ComponentPublicInstance,
@@ -28,7 +28,6 @@ export function emitted<T = unknown>(
 }
 
 export const attachEmitListener = () => {
-  events = {}
   // use devtools to capture this "emit"
   setDevtoolsHook(createDevTools(events), {})
 }
@@ -65,3 +64,8 @@ export const recordEvent = (
   // Record the event message sent by the emit
   events[cid][event].push(args)
 }
+
+export const removeEventHistory = (vm: ComponentPublicInstance): void => {
+  const cid = vm.$.uid
+  delete events[cid]
+}

src/vueWrapper.ts

@@ -13,7 +13,7 @@ import domEvents from './constants/dom-events'
 import { VueElement, VueNode } from './types'
 import { mergeDeep } from './utils'
 import { getRootNodes } from './utils/getRootNodes'
-import { emitted, recordEvent } from './emit'
+import { emitted, recordEvent, removeEventHistory } from './emit'
 import BaseWrapper from './baseWrapper'
 import type { DOMWrapper } from './domWrapper'
 import {
@@ -182,6 +182,8 @@ export class VueWrapper<
         `wrapper.unmount() can only be called by the root wrapper`
       )
     }
+    // Clear emitted events cache for this component instance
+    removeEventHistory(this.vm)
 
     this.__app.unmount()
   }

tests/emit.spec.ts

@@ -364,4 +364,35 @@ describe('emitted', () => {
     expect(wrapper.emitted().bar[0]).toEqual(['mounted'])
     expect(wrapper.emitted().bar[1]).toEqual(['click'])
   })
+
+  it('does not clear all emitted event history on mount/unmount', async () => {
+    const Foo = defineComponent({
+      name: 'Foo',
+      emits: ['foo'],
+      setup(_, ctx) {
+        return () =>
+          h(
+            'div',
+            {
+              onClick: () => {
+                ctx.emit('foo', 'bar')
+              }
+            },
+            'hello world'
+          )
+      }
+    })
+
+    const wrapper1 = mount(Foo)
+    await wrapper1.trigger('click')
+    expect(wrapper1.emitted('foo')).toHaveLength(1)
+
+    const wrapper2 = mount(Foo)
+    await wrapper2.trigger('click')
+    expect(wrapper2.emitted('foo')).toHaveLength(1)
+    expect(wrapper1.emitted('foo')).toHaveLength(1) // ensuring that subsequent mount does not clear event history for other wrappers
+
+    wrapper1.unmount()
+    wrapper2.unmount()
+  })
 })