Mapper types don't apply everywhere they should for typescript-resolvers

Describe the bug Hey all, I opened a task for this a month ago, but I think the test case isn’t quite right. Sorry for disappearing there, I went offline for thanksgiving and this fell off my radar. I can fix, but I want to confirm that this is actually a problem and I’m not missing something.

Test case addition for #886 https://github.com/dotansimha/graphql-code-generator/commit/b1bf6983522211a0432392ff3d8cea6b014e98dc?diff=unified

So let’s say I’m writing a resolver using apollo-server for the following schema’s mutation: https://github.com/dotansimha/graphql-code-generator/blob/master/packages/plugins/typescript-resolvers/tests/typescript-resolvers.spec.ts#L779-L789

// Assume I have mapper from Post to PostEntity
const resolvers: { RootMutation: RootMutationResolvers.Resolvers } = {
  RootMutation: {
    async upvotePost(id) {
      // ... perform mutation code
      // reload entity
      const post = await PostEntity.findOne({ id });

     // This is a type error using the generated code
     // as UpvotePostPayload is presumably: (see 2 below)
      return { post };
    }
  }
} 

UpvotePostPayload is presumably here:

export interface UpvotePostPayload {
  post?: Maybe<Post>;
}

… but then I have to return Post in my upvotePost function, not PostEntity. Apollo handles nested resolvers fine.

What I expect this to essentially be, for RootMutationResolver is, notice the changes:

- export interface UpvotePostPayload {
+ export interface UpvotePostPayload<T = Post> {
-  post?: Maybe<Post>;
+  post?: Maybe<T>;
}

export namespace RootMutationResolvers {
  export interface Resolvers<Context = {}, TypeParent = {}> {
-     upvotePost?: UpvotePostResolver<Maybe<UpvotePostPayload>, TypeParent, Context>;
+    upvotePost?: UpvotePostResolver<Maybe<UpvotePostPayload<PostEntity>>, TypeParent, Context>;
  }
        
-  export type UpvotePostResolver<R = Maybe<UpvotePostPayload>, Parent = {}, Context = {}> = Resolver<R, Parent, Context, UpvotePostArgs>;
+ export type UpvotePostResolver<R = Maybe<UpvotePostPayload<PostEntity>>, Parent = {}, Context = {}> = Resolver<R, Parent, Context, UpvotePostArgs>;
    export interface UpvotePostArgs {
      id: string;
    }
  }

… as things stand now, I would have to map PostEntity to Post in this mutation, with all of Posts required fields filled in.

[dotansimha]

Fix available in 1.0.0 👍

[kamilkisiela]

It’s going to be fixed in the upcoming release, right @dotansimha ?