[explicit-function-return-type] Decorators being reported ESLint: Missing return type on function

[abrarazeem]

• I have tried restarting my IDE and the issue persists.
• I have updated to the latest version of the packages.
• I have read the FAQ and my problem is not listed.

Repro

{
  "rules": {
      "@typescript-eslint/explicit-function-return-type": ["error", {
      allowExpressions: true
    }]
  }
}

import { Controller, HttpCode, HttpStatus } from '@nestjs/common'
import { AppService } from './app.service'
// Actually it's imported from @nestjs/common package but for the sake of testing and quick glimpse adding here.
export declare const Get: (path?: string | string[]) => MethodDecorator

@Controller()
export class AppController {

  constructor(private readonly appService: AppService) {}

  @Get() // ESLint: Missing return type on function.(@typescript-eslint/explicit-function-return-type)
  @HttpCode(HttpStatus.OK)
  getHello() {

    return this.appService.getHello()
  }
}

Expected Result
Decorators shouldn't be reported as missing return type.

Actual Result

Missing return type on function.eslint@typescript-eslint/explicit-function-return-type

Versions

package	version
@typescript-eslint/eslint-plugin	4.9.0
@typescript-eslint/parser	4.9.0
TypeScript	4.1.2
ESLint	7.14.0
node	14.15.1

[bradzacher]

The error is higlighting the start of the function, not the decorator itself.

getHello has no return type.