issue-0859-bug2

Example Code

import Elysia, { t } from "elysia";
export default new Elysia().get(
  "/",
  async () => {
    // Bug: `b: 2` should not be included in the response object, yet it is.
    return { keys: [{ a: 1, b: 2 }], extra: true };
  },
  {
    response: t.Object(
      { keys: t.Array(t.Object({ a: t.Number() })) },
      { additionalProperties: true }
    ),
  }
);

Tests

Test	bun	node
test	🏃	🏃

test

bun

=== Test Execution ===
$ curl -s -D- "http://localhost:3000"
HTTP/1.1 200 OK
Content-Type: application/json
Date: Sun, 01 Jun 2025 06:24:16 GMT
Content-Length: 37

{"keys":[{"a":1,"b":2}],"extra":true}

=== Runtime Output ===
[runtime] Bun 1.2.15
Started development server: http://localhost:3000

node

=== Test Execution ===
$ curl -s -D- "http://localhost:3000"
HTTP/1.1 200 OK
Content-Type: application/json
Content-Length: 37
Date: Sun, 01 Jun 2025 06:24:18 GMT
Connection: keep-alive
Keep-Alive: timeout=5

{"keys":[{"a":1,"b":2}],"extra":true}

=== Runtime Output ===
(node:28) ExperimentalWarning: Type Stripping is an experimental feature and might change at any time
(Use `node --trace-warnings ...` to show where the warning was created)
[runtime] Node v22.16.0
🦊 Elysia is running at :::3000