Incorrect response type in afterHandle

[aryzing]

What version of Elysia is running?

1.2.10

What platform is your computer?

Linux 6.8.0-50-generic x86_64 x86_64

What steps can reproduce the bug?

Create a simple handler with an afterHandle such as,

import Elysia from "elysia";

export const app = new Elysia()
  .get(
    "/test1",
    () => {
      return { message: "Hello, World!" };
    },
    {
      afterHandle: ({ response }) => {
        console.log(response);
      },
    }
  )

The response prop is typed as never, although it's actually the object returned from the handler.

What is the expected behavior?

The type of response in afterHandle should match the returned object from the handler.

What do you see instead?

The type is never

Details

Additional information

No response

Have you try removing the node_modules and bun.lockb and try again yet?

yes

[aryzing]

Also, for some reason, when returning an error() from the route handler, the response value fails an instanceof check against ElysiaCustomStatusResponse:

function myAfterHandle({ response }) {
  if (response instanceof ElysiaCustomStatusResponse) { // <-- This always returns false
    console.log("Yes");
    return;
  }
}

Using the constructor name to get around the instanceof fail does work. Is there a better approach though?

function myAfterHandle2({ response }: { response: unknown }) {
  const constructorName = (() => {
    try {
      return response.constructor.name;
    } catch {
      return null;
    }
  })();

  if (constructorName === "ElysiaCustomStatusResponse") {
    return;
  }

  return new Response(customLogic(response));