ValidationPipe validates nullable Args set to null

Is there an existing issue for this?

[X] I have searched the existing issues

Current behavior

ValidationPipe validates nullable Args set to null, resulting in a validation error for nullable arg.

Minimum reproduction code

https://stackblitz.com/edit/nestjs-typescript-starter-f5fhvk?file=src%2Fmain.ts,package.json,src%2Fapp.module.ts,src%2Fapp.resolver.ts&terminal=start

Steps to reproduce

open provided stackblitz
run the following query query { sayHellow }
you get a validation error ("firstName must be a string")

Expected behavior

As the Arg is nullable, no validation should be done.

Package

[ ] I don't know. Or some 3rd-party package
[X] code>@nestjs/common</code
[ ] code>@nestjs/core</code
[ ] code>@nestjs/microservices</code
[ ] code>@nestjs/platform-express</code
[ ] code>@nestjs/platform-fastify</code
[ ] code>@nestjs/platform-socket.io</code
[ ] code>@nestjs/platform-ws</code
[ ] code>@nestjs/testing</code
[ ] code>@nestjs/websockets</code
[ ] Other (see below)

Other package

No response

NestJS version

10.2.6

Packages versions

[System Information] OS Version : Linux 5.0 NodeJS Version : v18.18.0 NPM Version : 9.4.2

[Nest CLI] Nest CLI Version : 10.1.18

[Nest Platform Information] platform-express version : 10.2.6 schematics version : 10.0.2 graphql version : 12.0.10 testing version : 10.2.6 apollo version : 12.0.10 common version : 10.2.6 core version : 10.2.6 cli version : 10.1.18

Node.js version

18.18.0

In which operating systems have you tested?

[ ] macOS
[ ] Windows
[X] Linux

Other

Related Issue: #3930 and commit 233bc860e728b706cfae1858bd601288f237befc: that takes care about not transforming null. My issue is about validating it.

nestjs / nest