Using multiple @ArgsType() classes combines those arguments into one object and assigns it to all parameters which are an @ArgsType

[NilsMoller]

Is there an existing issue for this?

• I have searched the existing issues

Current behavior

When using multiple parameters in a resolver (code-first), having multiple parameters which are @ArgsType() classes, they combine the objects together and assign the same object to all @ArgsType parameters.

Minimum reproduction code

https://github.com/NilsMoller/multiple-args-type-params-combine-minimum-repro

Steps to reproduce

1. Run nest new
2. Run npm i @nestjs/graphql @nestjs/apollo @apollo/server graphql
3. Modify app.module.ts:

@Module({
  imports: [
    GraphQLModule.forRoot<ApolloDriverConfig>({
      driver: ApolloDriver,
      autoSchemaFile: true,
    }),
  ],
  controllers: [AppController],
  providers: [AppService, AppResolver],
})
export class AppModule {}

4. Create an app.resolver.ts class:

@ArgsType()
export class Args1 {
  @Field() prop1: string;
}

@ArgsType()
export class Args2 {
  @Field() prop2: string;
}

@Resolver()
export class AppResolver {
  @Query(() => String)
  hello(@Args() arg1: Args1, @Args() arg2: Args2) {
    return 'Hello World!';
  }
}

5. Start the app and breakpoint on return 'Hello World!' and see both arg1 and arg2 to be the same object.

arg1 = Object { prop1: "prop1", prop2: "prop2" }
arg2 = Object { prop1: "prop1", prop2: "prop2" }

Expected behavior

To have the arguments receive the same object structure as their class defines:

arg1 = Object { prop1: "prop1" }
arg2 = Object { prop2: "prop2" }

This would cause problems when both classes have the same key. In that case, I would expect to have one override the other (perhaps the last one passed), or an error to be thrown before the server starts.

Package version

^12.0.11

Graphql version

@apollo/server: ^4.9.5
@nestjs/apollo: ^12.0.11
graphql: ^16.8.1

NestJS version

^10.0.0

Node.js version

18.17.0

In which operating systems have you tested?

• macOS
• Windows
• Linux

Other

No response

[kamilmysliwiec]

You should never use multiple @Args() annotations in one method as there's only one args object in the context of a graphql resolver function, and Nest doesn't perform any pre-invocation object restructuring based on the class metadata due to performance reasons (+ it doesn't seem to be very useful/common use case anyway).

This is the expected behavior. Apologies if this caused any inconvenience!