[typescript-operations] operation type not restricted to inline fragment

[OscarBarrett]

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Describe the bug typescript-operations does not appear to take into account the specific inline fragments used, instead generating a type that could include anything from the returned interface.

To Reproduce Have two or more types that share an interface.

Define a query that returns the interface, but only include one of the types in an inline fragment.

Codesandbox: https://codesandbox.io/s/long-http-1wibc

1. My GraphQL schema:

type Query {
    entries(type: [String]): EntryInterface
}

interface EntryInterface {
    title: String
}

type first_Entry implements EntryInterface {
    title: String
    first: String
}

type second_Entry implements EntryInterface {
    title: String
    second: String
}

2. My GraphQL operations:

query first {
    entries(type: "first") {
        ...on first_Entry {
            __typename
            title
            first
        }
    }
}

3. My codegen.yml config file:

schema: schema.graphql
documents: document.graphql
generates:
  types.ts:
    plugins:
      - typescript
      - typescript-operations

Expected behavior

FirstQuery is generated as follows:

export type FirstQuery = {
  __typename ? : 'Query',
  entries ? : {
    __typename: 'first_Entry',
    title ? : string | null | undefined,
    first ? : string | null | undefined
  } | {
    __typename ? : 'second_Entry'
  } | null | undefined
};

The expected type would be:

export type FirstQuery = {
  __typename ? : 'Query',
  entries ? : {
    __typename: 'first_Entry',
    title ? : string | null | undefined,
    first ? : string | null | undefined
  } | null | undefined
};

(i.e. no { __typename?: 'second_Entry' } in the union).

Environment:

• OS: MacOS
• @graphql-codegen/typescript: 2.2.4
• @graphql-codegen/typescript-operations: 2.1.8
• NodeJS: 14

Additional context In typescript-operations v1, when using skipTypename: true objects only containing __typename? would be removed, so this could be avoided. In v2 the union will include {} instead.

[gbettencourt]

Hitting this same issue, which is preventing us from updating. We'd have to make type assertions to force the correct type which is not ideal.

[peternedap]

I'm running into the same problem. This is also preventing an upgrade to graphql 16 in our codebase. This problem is especially annoying when using skipTypename:true, as there are no fields that can help us narrow the resulting type of a query.

[nandorojo]

Looks like this is still a thing for me. Makes inline fragments pretty challenging to work with type-wise, as I have to do tons of type name conditionals just to read a field which should be marked as optional.

[nelsonchen5]

+1

[erickreutz]

Running into this issue as well

[ktaletski]

Same here