fix(types): make return type of defineComponent assignable to Component type (#1032)

fix #993

packages/runtime-core/src/apiDefineComponent.ts

@@ -5,7 +5,7 @@ import {
   ComponentOptionsWithArrayProps,
   ComponentOptionsWithObjectProps
 } from './componentOptions'
-import { SetupContext, RenderFunction } from './component'
+import { SetupContext, RenderFunction, FunctionalComponent } from './component'
 import { ComponentPublicInstance } from './componentProxy'
 import { ExtractPropTypes, ComponentPropsOptions } from './componentProps'
 import { EmitsOptions } from './componentEmits'
@@ -34,7 +34,7 @@ export function defineComponent<Props, RawBindings = object>(
     // public props
     VNodeProps & Props
   >
-}
+} & FunctionalComponent<Props>
 
 // overload 2: object format with no props
 // (uses user defined props interface)
@@ -59,7 +59,7 @@ export function defineComponent<
     E,
     VNodeProps & Props
   >
-}
+} & ComponentOptionsWithoutProps<Props, RawBindings, D, C, M, E, EE>
 
 // overload 3: object format with array props declaration
 // props inferred as { [key in PropNames]?: any }
@@ -85,7 +85,7 @@ export function defineComponent<
 ): {
   // array props technically doesn't place any contraints on props in TSX
   new (): ComponentPublicInstance<VNodeProps, RawBindings, D, C, M, E>
-}
+} & ComponentOptionsWithArrayProps<PropNames, RawBindings, D, C, M, E, EE>
 
 // overload 4: object format with object props declaration
 // see `ExtractPropTypes` in ./componentProps.ts
@@ -119,7 +119,7 @@ export function defineComponent<
     E,
     VNodeProps & ExtractPropTypes<PropsOptions, false>
   >
-}
+} & ComponentOptionsWithObjectProps<PropsOptions, RawBindings, D, C, M, E, EE>
 
 // implementation, close to no-op
 export function defineComponent(options: unknown) {

packages/runtime-core/src/h.ts

@@ -67,6 +67,11 @@ interface Constructor<P = any> {
   new (): { $props: P }
 }
 
+// Excludes Component type from returned `defineComponent`
+type NotDefinedComponent<T extends Component> = T extends Constructor
+  ? never
+  : T
+
 // The following is a series of overloads for providing props validation of
 // manually written render functions.
 
@@ -110,8 +115,10 @@ export function h<P>(
 
 // catch-all for generic component types
 export function h(type: Component, children?: RawChildren): VNode
-export function h(
-  type: ComponentOptions | FunctionalComponent<{}>,
+
+// exclude `defineComponent`
+export function h<Options extends ComponentOptions | FunctionalComponent<{}>>(
+  type: NotDefinedComponent<Options>,
   props?: RawProps | null,
   children?: RawChildren | RawSlots
 ): VNode