response-validation-additional-properties

Example Code

import { Elysia, t } from "elysia";
export default new Elysia().get(
  "/",
  async () => {
    return { a: 1, b: 2 };
  },
  { response: 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 06:23:50 GMT
Content-Length: 13

{"a":1,"b":2}
✓ expect: 200
✓ expect: b

=== 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: 13
Date: Sun, 01 Jun 2025 06:23:51 GMT
Connection: keep-alive
Keep-Alive: timeout=5

{"a":1,"b":2}
✓ expect: 200
✓ expect: b

=== 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