wip: vm.$listeners compat

packages/runtime-core/src/compat/deprecations.ts

@@ -23,6 +23,7 @@ export const enum DeprecationTypes {
   INSTANCE_EVENT_EMITTER = 'INSTANCE_EVENT_EMITTER',
   INSTANCE_EVENT_HOOKS = 'INSTANCE_EVENT_HOOKS',
   INSTANCE_CHILDREN = 'INSTANCE_CHILDREN',
+  INSTANCE_LISTENERS = 'INSTANCE_LISTENERS',
 
   OPTIONS_DATA_FN = 'OPTIONS_DATA_FN',
   OPTIONS_DATA_MERGE = 'OPTIONS_DATA_MERGE',
@@ -173,6 +174,14 @@ const deprecationData: Record<DeprecationTypes, DeprecationData> = {
     link: `https://v3.vuejs.org/guide/migration/children.html`
   },
 
+  [DeprecationTypes.INSTANCE_LISTENERS]: {
+    message:
+      `vm.$listeners has been removed. Parent v-on listeners are now ` +
+      `included in vm.$attrs and it is no longer necessary to separately use ` +
+      `v-on="$listeners" if you are already using v-bind="$attrs".`,
+    link: `https://v3.vuejs.org/guide/migration/listeners-removed.html`
+  },
+
   [DeprecationTypes.OPTIONS_DATA_FN]: {
     message:
       `The "data" option can no longer be a plain object. ` +

packages/runtime-core/src/compat/instance.ts

@@ -1,9 +1,10 @@
 import { extend, NOOP } from '@vue/shared'
 import { PublicPropertiesMap } from '../componentPublicInstance'
-import { getInstanceChildren } from './children'
+import { getCompatChildren } from './instanceChildren'
 import { assertCompatEnabled } from './compatConfig'
 import { DeprecationTypes } from './deprecations'
-import { off, on, once } from './eventEmitter'
+import { off, on, once } from './instanceEventEmitter'
+import { getCompatListeners } from './instanceListeners'
 
 export function installCompatInstanceProperties(map: PublicPropertiesMap) {
   const set = (target: any, key: any, val: any) => {
@@ -36,6 +37,7 @@ export function installCompatInstanceProperties(map: PublicPropertiesMap) {
     $on: i => on.bind(null, i),
     $once: i => once.bind(null, i),
     $off: i => off.bind(null, i),
-    $children: getInstanceChildren
+    $children: getCompatChildren,
+    $listeners: getCompatListeners
   } as PublicPropertiesMap)
 }

packages/runtime-core/src/compat/instanceChildren.ts

@@ -5,7 +5,7 @@ import { VNode } from '../vnode'
 import { assertCompatEnabled } from './compatConfig'
 import { DeprecationTypes } from './deprecations'
 
-export function getInstanceChildren(
+export function getCompatChildren(
   instance: ComponentInternalInstance
 ): ComponentPublicInstance[] {
   assertCompatEnabled(DeprecationTypes.INSTANCE_CHILDREN)

packages/runtime-core/src/compat/instanceListeners.ts

@@ -0,0 +1,20 @@
+import { isOn } from '@vue/shared'
+import { ComponentInternalInstance } from '../component'
+import { assertCompatEnabled } from './compatConfig'
+import { DeprecationTypes } from './deprecations'
+
+export function getCompatListeners(instance: ComponentInternalInstance) {
+  assertCompatEnabled(DeprecationTypes.INSTANCE_LISTENERS)
+
+  const listeners: Record<string, Function | Function[]> = {}
+  const rawProps = instance.vnode.props
+  if (!rawProps) {
+    return listeners
+  }
+  for (const key in rawProps) {
+    if (isOn(key)) {
+      listeners[key[2].toLowerCase() + key.slice(3)] = rawProps[key]
+    }
+  }
+  return listeners
+}

packages/runtime-core/src/compat/renderFn.ts

@@ -0,0 +1,99 @@
+import { isArray, isObject } from '@vue/shared'
+import { Component, Data } from '../component'
+import {
+  createVNode,
+  isVNode,
+  VNode,
+  VNodeArrayChildren,
+  VNodeProps
+} from '../vnode'
+
+interface LegacyVNodeProps {
+  key?: string | number
+  ref?: string
+  refInFor?: boolean
+
+  staticClass?: string
+  class?: unknown
+  staticStyle?: Record<string, unknown>
+  style?: Record<string, unknown>
+  attrs?: Record<string, unknown>
+  domProps?: Record<string, unknown>
+  on?: Record<string, Function | Function[]>
+  nativeOn?: Record<string, Function | Function[]>
+  directives?: LegacyVNodeDirective[]
+
+  slot?: string
+  scopedSlots?: Record<string, Function>
+}
+
+interface LegacyVNodeDirective {
+  name: string
+  value: unknown
+  arg?: string
+  modifiers?: Record<string, boolean>
+}
+
+type LegacyVNodeChildren =
+  | string
+  | number
+  | boolean
+  | VNode
+  | VNodeArrayChildren
+
+export function h(
+  type: string | Component,
+  children?: LegacyVNodeChildren
+): VNode
+export function h(
+  type: string | Component,
+  props?: LegacyVNodeProps,
+  children?: LegacyVNodeChildren
+): VNode
+
+export function h(type: any, propsOrChildren?: any, children?: any): VNode {
+  const l = arguments.length
+  if (l === 2) {
+    if (isObject(propsOrChildren) && !isArray(propsOrChildren)) {
+      // single vnode without props
+      if (isVNode(propsOrChildren)) {
+        return convertLegacySlots(createVNode(type, null, [propsOrChildren]))
+      }
+      // props without children
+      return convertLegacyDirectives(
+        createVNode(type, convertLegacyProps(propsOrChildren)),
+        propsOrChildren
+      )
+    } else {
+      // omit props
+      return convertLegacySlots(createVNode(type, null, propsOrChildren))
+    }
+  } else {
+    if (l > 3) {
+      children = Array.prototype.slice.call(arguments, 2)
+    } else if (l === 3 && isVNode(children)) {
+      children = [children]
+    }
+    return convertLegacySlots(
+      convertLegacyDirectives(
+        createVNode(type, convertLegacyProps(propsOrChildren), children),
+        propsOrChildren
+      )
+    )
+  }
+}
+
+function convertLegacyProps(props: LegacyVNodeProps): Data & VNodeProps {
+  // TODO
+  return {}
+}
+
+function convertLegacyDirectives(vnode: VNode, props: LegacyVNodeProps): VNode {
+  // TODO
+  return vnode
+}
+
+function convertLegacySlots(vnode: VNode): VNode {
+  // TODO
+  return vnode
+}