feat: implement wrapper.emitted() and wrapper.emittedByOrder()

Author: yyx990803

src/lib/log-events.js

@@ -0,0 +1,8 @@
+export function logEvents (vm, emitted, emittedByOrder) {
+  const emit = vm.$emit
+  vm.$emit = (name, ...args) => {
+    (emitted[name] || (emitted[name] = [])).push(args)
+    emittedByOrder.push({ name, args })
+    return emit.call(vm, name, ...args)
+  }
+}

src/wrappers/vue-wrapper.js

@@ -1,12 +1,16 @@
 // @flow
 
 import Wrapper from './wrapper'
+import { logEvents } from '../lib/log-events'
 
 function update () {
   this._update(this._render())
 }
 
 export default class VueWrapper extends Wrapper implements BaseWrapper {
+  _emitted: { [name: string]: Array<Array<any>> };
+  _emittedByOrder: Array<{ name: string; args: Array<any> }>;
+
   constructor (vm: Component, options: WrapperOptions) {
     super(vm._vnode, update.bind(vm), options)
 
@@ -18,5 +22,17 @@ export default class VueWrapper extends Wrapper implements BaseWrapper {
 
     this.vm = vm
     this.isVueComponent = true
+    this._emitted = Object.create(null)
+    this._emittedByOrder = []
+
+    logEvents(vm, this._emitted, this._emittedByOrder)
+  }
+
+  emitted () {
+    return this._emitted
+  }
+
+  emittedByOrder () {
+    return this._emittedByOrder
   }
 }

test/unit/specs/mount/Wrapper/emitted.spec.js

@@ -0,0 +1,31 @@
+import mount from '~src/mount'
+
+describe('emitted', () => {
+  it('captures emitted events', () => {
+    const wrapper = mount({
+      render: h => h('div')
+    })
+
+    wrapper.vm.$emit('foo')
+    expect(wrapper.emitted().foo).to.exist
+    expect(wrapper.emitted().foo.length).to.equal(1)
+    expect(wrapper.emitted().foo[0]).to.eql([])
+
+    expect(wrapper.emitted().bar).not.to.exist
+    wrapper.vm.$emit('bar', 1, 2, 3)
+    expect(wrapper.emitted().bar).to.exist
+    expect(wrapper.emitted().bar.length).to.equal(1)
+    expect(wrapper.emitted().bar[0]).to.eql([1, 2, 3])
+
+    wrapper.vm.$emit('foo', 2, 3, 4)
+    expect(wrapper.emitted().foo).to.exist
+    expect(wrapper.emitted().foo.length).to.equal(2)
+    expect(wrapper.emitted().foo[1]).to.eql([2, 3, 4])
+
+    expect(wrapper.emittedByOrder()).to.eql([
+      { name: 'foo', args: [] },
+      { name: 'bar', args: [1, 2, 3] },
+      { name: 'foo', args: [2, 3, 4] }
+    ])
+  })
+})