types: props validation for h

packages/runtime-core/src/h.ts

@@ -1,5 +1,22 @@
-import { VNodeTypes, VNode, createVNode } from './vnode'
+import {
+  VNodeTypes,
+  VNode,
+  createVNode,
+  VNodeChildren,
+  Fragment,
+  Portal
+} from './vnode'
 import { isObject, isArray } from '@vue/shared'
+import { Ref } from '@vue/reactivity'
+import { RawSlots } from './componentSlots'
+import {
+  FunctionalComponent,
+  ComponentOptions,
+  ComponentOptionsWithoutProps,
+  ComponentOptionsWithArrayProps,
+  ComponentOptionsWithProps
+} from './component'
+import { ExtractPropTypes } from './componentProps'
 
 // `h` is a more user-friendly version of `createVNode` that allows omitting the
 // props when possible. It is intended for manually written render functions.
@@ -30,6 +47,87 @@ h('div', {}, 'foo') // text
 h('div', null, {})
 **/
 
+interface Props {
+  [key: string]: any
+  key?: string | number
+  ref?: string | Ref<any> | Function
+  // used to differ from a single VNode object as children
+  _isVNode?: never
+  // used to differ from Array children
+  [Symbol.iterator]?: never
+}
+
+type Children = string | number | VNodeChildren
+
+// fake constructor type returned from `createComponent`
+interface Constructor<P = any> {
+  new (): { $props: P }
+}
+
+// The following is a series of overloads for providing props validation of
+// manually written render functions.
+
+// element
+export function h(type: string, children?: Children): VNode
+export function h(
+  type: string,
+  props?: Props | null,
+  children?: Children
+): VNode
+
+// keyed fragment
+export function h(type: typeof Fragment, children?: Children): VNode
+export function h(
+  type: typeof Fragment,
+  props?: (Props & { key?: string | number }) | null,
+  children?: Children
+): VNode
+
+// portal
+export function h(type: typeof Portal, children?: Children): VNode
+export function h(
+  type: typeof Portal,
+  props?: (Props & { target: any }) | null,
+  children?: Children
+): VNode
+
+// functional component
+export function h(type: FunctionalComponent, children?: Children): VNode
+export function h<P>(
+  type: FunctionalComponent<P>,
+  props?: (Props & P) | null,
+  children?: Children | RawSlots
+): VNode
+
+// stateful component
+export function h(type: ComponentOptions, children?: Children): VNode
+export function h<P>(
+  type: ComponentOptionsWithoutProps<P>,
+  props?: (Props & P) | null,
+  children?: Children | RawSlots
+): VNode
+export function h<P extends string>(
+  type: ComponentOptionsWithArrayProps<P>,
+  // TODO for now this doesn't really do anything, but it would become useful
+  // if we make props required by default
+  props?: (Props & { [key in P]?: any }) | null,
+  children?: Children | RawSlots
+): VNode
+export function h<P>(
+  type: ComponentOptionsWithProps<P>,
+  props?: (Props & ExtractPropTypes<P>) | null,
+  children?: Children | RawSlots
+): VNode
+
+// fake constructor type returned by `createComponent`
+export function h(type: Constructor, children?: Children): VNode
+export function h<P>(
+  type: Constructor<P>,
+  props?: (Props & P) | null,
+  children?: Children | RawSlots
+): VNode
+
+// Actual implementation
 export function h(
   type: VNodeTypes,
   propsOrChildren?: any,