fix: forward dispatch return value (nodejs#3368)

lib/dispatcher/dispatcher.js

@@ -35,30 +35,9 @@ class Dispatcher extends EventEmitter {
       }
     }
 
-    return new ComposedDispatcher(this, dispatch)
-  }
-}
-
-class ComposedDispatcher extends Dispatcher {
-  #dispatcher = null
-  #dispatch = null
-
-  constructor (dispatcher, dispatch) {
-    super()
-    this.#dispatcher = dispatcher
-    this.#dispatch = dispatch
-  }
-
-  dispatch (...args) {
-    this.#dispatch(...args)
-  }
-
-  close (...args) {
-    return this.#dispatcher.close(...args)
-  }
-
-  destroy (...args) {
-    return this.#dispatcher.destroy(...args)
+    return new Proxy(this, {
+      get: (target, key) => key === 'dispatch' ? dispatch : target[key]
+    })
   }
 }
 

test/dispatcher.js

@@ -22,14 +22,11 @@ test('dispatcher implementation', (t) => {
 })
 
 test('dispatcher.compose', (t) => {
-  t = tspl(t, { plan: 10 })
+  t = tspl(t, { plan: 7 })
 
   const dispatcher = new Dispatcher()
   const interceptor = () => (opts, handler) => {}
   // Should return a new dispatcher
-  t.ok(Object.getPrototypeOf(dispatcher.compose(interceptor)) instanceof Dispatcher)
-  t.ok(Object.getPrototypeOf(dispatcher.compose(interceptor, interceptor)) instanceof Dispatcher)
-  t.ok(Object.getPrototypeOf(dispatcher.compose([interceptor, interceptor])) instanceof Dispatcher)
   t.ok(dispatcher.compose(interceptor) !== dispatcher)
   t.throws(() => dispatcher.dispatch({}), Error, 'invalid interceptor')
   t.throws(() => dispatcher.dispatch(() => null), Error, 'invalid interceptor')