Can't use interceptor with optional parameter as type

[superpupervlad]

Is there an existing issue for this?

• [X] I have searched the existing issues

Current behavior

@UseInterceptors can't handle interceptor (with optional parameters) that passed as type.

Minimum reproduction code

https://stackblitz.com/edit/nestjs-typescript-starter-bnqkzn?file=src/app.controller.ts

Steps to reproduce

No response

Expected behavior

Due to documentation (leaving responsibility for instantiation to the framework and enabling dependency injection) nest should create an instance of interceptor because no parameters needed from user and it is possible to create interceptor.

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

8.1.1

Packages versions

From stackblitz

[Nest CLI]
Nest CLI Version : 8.1.3 

[Nest Platform Information]
platform-express version : 8.1.1
schematics version       : 8.0.4
testing version          : 8.1.1
common version           : 8.1.1
core version             : 8.1.1
cli version              : 8.1.3

Node.js version

16.14.2

In which operating systems have you tested?

• [ ] macOS
• [ ] Windows
• [X] Linux

Other

No response

[micalevisk]

your interceptor should have this constructor:

  constructor(
    @Optional() private first_optional_param?: string,
    @Optional() private second_optional_param: string = 'abc',
  ) {}

learn here: https://docs.nestjs.com/providers#optional-providers

[jmcdo29]

This is not a bug. Micael has the correct solution above.

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