Fastify reply functions wrongly typed

[g0di]

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• I have written a descriptive issue title
• I have searched existing issues to ensure the issue has not already been raised

Issue

Hi folks,

Looking at typings for fastify reply decorations added by this library in httpError.d.ts

// Line 103
export type HttpErrorReplys = {
  getHttpError: (code: HttpErrorCodes, message?: string) => void;
} & Record<HttpErrorNames, (msg?: string) => void>;

it looks like that those functions (rep.internalServerError('') for example) should return void.

However, looking at the implementation in index.js

// Line 47
fastify.decorateReply(httpError, function (message) {
  this.send(httpErrors[httpError](message))
  return this
})

it looks like that the reply object is returned after calling send function.

Could it be possible to align the typings so I can do the following in my code without a 'await' has no effect on the type of this expression.ts(80007) message and ESLint being mad?

fastify.get('/', { 
  async handler(req, rep) {
    return await rep.internalServerError('Oops')
  }
}

Thanks

[Eomm]

Thanks for reporting!
Would you like to send a Pull Request to address this issue? Remember to add unit tests.

[g0di]

I'll try if I got some spare time. About tests, what kind of tests you would? Just ensuring the functions actually return the reply object and not void?

[mcollina]

check out https://github.com/fastify/fastify-sensible/blob/master/types/index.test-d.ts