Wrong typings for MessageHandler

[dkonasov]

Is there an existing issue for this?

• I have searched the existing issues

Current behavior

Return type of MessageHandler function is Promise<Observable<TResult>>, while actually it returns Promise<TResult>.

Minimum reproduction code

https://github.com/dkonasov/message-handler-typings-bug-demo/blob/b96262ee988bd62ab71f4dc6cbbfc996dcb1ab8b/src/demo-strategy.ts#L12

Steps to reproduce

No response

Expected behavior

Should be typed according to real return value

Package

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

Other package

No response

NestJS version

8.4.5

Packages versions

platform-express version : 8.4.5
microservices version    : 8.4.5
schematics version       : 8.0.11
testing version          : 8.4.5
common version           : 8.4.5
core version             : 8.4.5
cli version              : 8.2.6

Node.js version

16.13.2

In which operating systems have you tested?

• macOS
• Windows
• Linux

Other

No response

[kamilmysliwiec]

Type should be Promise<Observable<TResult>> | Promise<TResult>. Would you like to create a PR for this issue?

[dkonasov]

Type should be Promise<Observable<TResult>> | Promise<TResult>. Would you like to create a PR for this issue?

Yes, I'll create it in a next few days, thanks =)

[kamilmysliwiec]

Let's track this here #9674