`example` & `default` properties not behavie as expected

Is there an existing issue for this?

[X] I have searched the existing issues

Current behavior

The Swagger page is taking default values from the example property in the declaration.

Screenshot 2023-06-15 at 20 24 49

This is especially an issue when the property is an array due to there is no way to really not sent the query param:

Screenshot 2023-06-15 at 20 28 39

Minimum reproduction code

https://stackblitz.com/edit/nestjs-typescript-starter-aprkdl?file=src%2Fapp.controller.ts

Steps to reproduce

Declare an optional property as in:

  // input text will have `something` as value
  @ApiPropertyOptional({
    default: 'default is ignored',
    description: 'some string',
    example: 'something',
  })
  q?: string;

  // No option selected but the request will include `?options=one`
  @ApiPropertyOptional({
    description: 'some options',
    enum: OPTIONS,
    example: OPTIONS[0],
    isArray: true,
  })
  options?: (typeof OPTIONS)[number];

Expected behavior

Default values in SwaggerUI should not be taken from the example property but from the default if there is any

Package

[ ] I don't know. Or some 3rd-party package
[ ] 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
[X] Other (see below)

Other package

@nestjs/swagger

NestJS version

9.0.0

Packages versions

  "dependencies": {
    "@nestjs/common": "^9.0.0",
    "@nestjs/core": "^9.0.0",
    "@nestjs/platform-express": "^9.0.0",
    "@nestjs/swagger": "^6.3.0",
    "reflect-metadata": "^0.1.13",
    "rxjs": "^7.2.0"
  },

Node.js version

v18.16.0

In which operating systems have you tested?

[X] macOS
[ ] Windows
[ ] Linux

Other

No response

nestjs / nest

`example` & `default` properties not behavie as expected #11809