Why are fragments generated with typescript-operation T | null | undefined?

[alexrhogue]

Hey I've been trying to understand why graphql operation fragments for nullable fields are generated with undefined in the union.

For example:

# Schema
type User implements Node {
  id: ID!
  username: String # this field is nullable
  role: Role!
}

# Operations
query findUser($userId: ID!) {
  user(id: $userId) {
    ...UserFields
  }
}

fragment UserFields on User {
  id
  username
  role
}

Generate the following

export type UserFieldsFragment = { 
  id: string, 
  username: string | null | undefined, // <- this field
  role: Types.Role 
};

Graphql will return what is asked for in a query, so it will always return either string or null, correct? The types generated for the backend seem to match this, but not the fragment and query generation for the frontend.

Can anyone:

1. Help me understand this behavior?
2. Have any ideas how to avoid this behavior? 😆

Thanks!

[alexrhogue]

Seems fixed in the recent versions