Merge pull request #119 from vuejs/fix/add-parameter-to-emit

fix: Allow passing an event name to the `emitted` method

Author: lmiller1990

src/vue-wrapper.ts

@@ -68,10 +68,14 @@ export class VueWrapper<T extends ComponentPublicInstance> {
     return true
   }
 
-  emitted(): Record<string, unknown[]> {
-    // TODO Should we define this?
-    // @ts-ignore
-    return this.vm.__emitted
+  emitted<T = unknown>(): Record<string, T[]>
+  emitted<T = unknown>(eventName?: string): T[]
+  emitted<T = unknown>(eventName?: string): T[] | Record<string, T[]> {
+    if (eventName) {
+      const emitted = (this.vm['__emitted'] as Record<string, T[]>)[eventName]
+      return emitted
+    }
+    return this.vm['__emitted'] as Record<string, T[]>
   }
 
   html() {

test-dts/wrapper.d-test.ts

@@ -61,6 +61,15 @@ expectType<SVGLineElement | undefined>(lineArray[0].element)
 byClassArray = domWrapper.findAll('.todo')
 expectType<Element | undefined>(byClassArray[0].element)
 
+// emitted
+// event name
+let incrementEvent = wrapper.emitted<{ count: number }>('increment')
+expectType<{ count: number }>(incrementEvent[0])
+
+// without event name
+let allEvents = wrapper.emitted()
+expectType<Record<string, unknown[]>>(allEvents)
+
 // get
 // HTML element selector
 let input = wrapper.get('input')

tests/emit.spec.ts

@@ -96,4 +96,29 @@ describe('emitted', () => {
     wrapper.find('button').trigger('click')
     expect(wrapper.emitted().parent[1]).toEqual(['foo', 'bar'])
   })
+
+  it('should allow passing the name of an event', () => {
+    const Component = defineComponent({
+      name: 'ContextEmit',
+
+      setup(props, ctx) {
+        return () =>
+          h('div', [
+            h('button', { onClick: () => ctx.emit('hello', 'foo', 'bar') })
+          ])
+      }
+    })
+    const wrapper = mount(Component)
+
+    // test what happens if you pass a none existent event
+    expect(wrapper.emitted('hello')).toEqual(undefined)
+
+    wrapper.find('button').trigger('click')
+    expect(wrapper.emitted('hello')[0]).toEqual(['foo', 'bar'])
+
+    wrapper.find('button').trigger('click')
+    expect(wrapper.emitted('hello')[1]).toEqual(['foo', 'bar'])
+
+    expect(wrapper.emitted('hello')).toHaveLength(2)
+  })
 })