types(defineComponent): Support emit when using functionalComponent

Author: pikax

packages/runtime-core/src/apiDefineComponent.ts

@@ -80,10 +80,14 @@ export type DefineComponent<
 
 // overload 1: direct setup function
 // (uses user defined props interface)
-export function defineComponent<Props, RawBindings = object>(
+export function defineComponent<
+  Props,
+  RawBindings = object,
+  E extends EmitsOptions = {}
+>(
   setup: (
     props: Readonly<Props>,
-    ctx: SetupContext
+    ctx: SetupContext<E>
   ) => RawBindings | RenderFunction
 ): DefineComponent<Props, RawBindings>
 

test-dts/component.test-d.ts

@@ -410,6 +410,15 @@ describe('functional', () => {
 
     expectType<number>(props.foo)
   })
+
+  describe('emit', () => {
+    const MyComponent: FunctionalComponent<
+      { foo: number },
+      { ev: (a: string) => void }
+    > = (_, _2) => {}
+
+    defineComponent(MyComponent)
+  })
 })
 
 declare type VueClass<Props = {}> = {