feat(runtime-core): emit now returns array of return values from all triggered handlers

close #635

packages/runtime-core/__tests__/component.spec.ts

@@ -1,4 +1,11 @@
-import { h, ref, render, nodeOps, nextTick } from '@vue/runtime-test'
+import {
+  h,
+  ref,
+  render,
+  nodeOps,
+  nextTick,
+  defineComponent
+} from '@vue/runtime-test'
 
 describe('renderer: component', () => {
   test.todo('should work')
@@ -52,4 +59,35 @@ describe('renderer: component', () => {
       expect(spy).toHaveBeenCalledTimes(2)
     })
   })
+
+  test('emit', async () => {
+    let noMatchEmitResult: any
+    let singleEmitResult: any
+    let multiEmitResult: any
+
+    const Child = defineComponent({
+      setup(_, { emit }) {
+        noMatchEmitResult = emit('foo')
+        singleEmitResult = emit('bar')
+        multiEmitResult = emit('baz')
+        return () => h('div')
+      }
+    })
+
+    const App = {
+      setup() {
+        return () =>
+          h(Child, {
+            onBar: () => 1,
+            onBaz: [() => Promise.resolve(2), () => Promise.resolve(3)]
+          })
+      }
+    }
+
+    render(h(App), nodeOps.createElement('div'))
+
+    expect(noMatchEmitResult).toMatchObject([])
+    expect(singleEmitResult).toMatchObject([1])
+    expect(await Promise.all(multiEmitResult)).toMatchObject([2, 3])
+  })
 })

packages/runtime-core/__tests__/errorHandling.spec.ts

@@ -362,7 +362,7 @@ describe('error handling', () => {
     expect(fn).toHaveBeenCalledWith(err, 'watcher cleanup function')
   })
 
-  test('in component event handler', () => {
+  test('in component event handler via emit', () => {
     const err = new Error('foo')
     const fn = jest.fn()
 
@@ -392,6 +392,78 @@ describe('error handling', () => {
     expect(fn).toHaveBeenCalledWith(err, 'component event handler')
   })
 
+  test('in component event handler via emit (async)', async () => {
+    const err = new Error('foo')
+    const fn = jest.fn()
+
+    const Comp = {
+      setup() {
+        onErrorCaptured((err, instance, info) => {
+          fn(err, info)
+          return true
+        })
+        return () =>
+          h(Child, {
+            async onFoo() {
+              throw err
+            }
+          })
+      }
+    }
+
+    let res: any
+    const Child = {
+      setup(props: any, { emit }: any) {
+        res = emit('foo')
+        return () => null
+      }
+    }
+
+    render(h(Comp), nodeOps.createElement('div'))
+
+    try {
+      await Promise.all(res)
+    } catch (e) {
+      expect(e).toBe(err)
+    }
+    expect(fn).toHaveBeenCalledWith(err, 'component event handler')
+  })
+
+  test('in component event handler via emit (async + array)', async () => {
+    const err = new Error('foo')
+    const fn = jest.fn()
+
+    const Comp = {
+      setup() {
+        onErrorCaptured((err, instance, info) => {
+          fn(err, info)
+          return true
+        })
+        return () =>
+          h(Child, {
+            onFoo: [() => Promise.reject(err), () => Promise.resolve(1)]
+          })
+      }
+    }
+
+    let res: any
+    const Child = {
+      setup(props: any, { emit }: any) {
+        res = emit('foo')
+        return () => null
+      }
+    }
+
+    render(h(Comp), nodeOps.createElement('div'))
+
+    try {
+      await Promise.all(res)
+    } catch (e) {
+      expect(e).toBe(err)
+    }
+    expect(fn).toHaveBeenCalledWith(err, 'component event handler')
+  })
+
   it('should warn unhandled', () => {
     const onError = jest.spyOn(console, 'error')
     onError.mockImplementation(() => {})