Duplicate identifier on Typescript type generation due to _ prefix

Describe the bug On generating GraphQL schema (using Typescript + Typescript-Operations plugins), duplicate fields are generated: TS2300: Duplicate identifier error

To Reproduce Having a graphql endpoint and then run the command yarn graphql-codegen --config codegen.yml -r dotenv/config (or using npm)

The bug happen when a GraphQL schema has key like _createdAt_ASC and createdAt_ASC, the _ is ignore and the generated type definition create two createdAt_ASC

1. My GraphQL schema:

_createdAt_ASC
_createdAt_DESC
createdAt_ASC
createdAt_DESC
id_ASC
id_DESC
_firstPublishedAt_ASC
_firstPublishedAt_DESC
_publicationScheduledAt_ASC
_publicationScheduledAt_DESC
_unpublishingScheduledAt_ASC
_unpublishingScheduledAt_DESC
_publishedAt_ASC
_publishedAt_DESC
_status_ASC
_status_DESC
_updatedAt_ASC
_updatedAt_DESC
updatedAt_ASC
updatedAt_DESC
_isValid_ASC
_isValid_DESC
title_ASC
title_DESC

1. My codegen.yml config file:

overwrite: true

schema:
  - '${GRAPHQL_API_ENDPOINT}':
      headers:
        Authorization: 'Bearer ${GRAPHQL_API_TOKEN}'

documents: core/queries/**/*.ts
generates:
  core/queries/schema.ts:
    plugins:
      - 'typescript'
      - 'typescript-operations'

1. My schema output:

export enum ArticleModelOrderBy {
  CreatedAtAsc = '_createdAt_ASC',
  CreatedAtDesc = '_createdAt_DESC',
  FirstPublishedAtAsc = '_firstPublishedAt_ASC',
  FirstPublishedAtDesc = '_firstPublishedAt_DESC',
  IsValidAsc = '_isValid_ASC',
  IsValidDesc = '_isValid_DESC',
  PublicationScheduledAtAsc = '_publicationScheduledAt_ASC',
  PublicationScheduledAtDesc = '_publicationScheduledAt_DESC',
  PublishedAtAsc = '_publishedAt_ASC',
  PublishedAtDesc = '_publishedAt_DESC',
  StatusAsc = '_status_ASC',
  StatusDesc = '_status_DESC',
  UnpublishingScheduledAtAsc = '_unpublishingScheduledAt_ASC',
  UnpublishingScheduledAtDesc = '_unpublishingScheduledAt_DESC',
  UpdatedAtAsc = '_updatedAt_ASC', 
  UpdatedAtDesc = '_updatedAt_DESC',
  CreatedAtAsc = 'createdAt_ASC', // duplicate
  CreatedAtDesc = 'createdAt_DESC',  // duplicate
  IdAsc = 'id_ASC',
  IdDesc = 'id_DESC',
  TitleAsc = 'title_ASC',
  TitleDesc = 'title_DESC',
  UpdatedAtAsc = 'updatedAt_ASC',  // duplicate
  UpdatedAtDesc = 'updatedAt_DESC'  // duplicate
}

Expected behavior

Environment: Darwin Majdis-MacBook-Pro.local 20.6.0 Darwin Kernel Version 20.6.0: Mon Aug 30 06:12:21 PDT 2021; root:xnu-7195.141.6~3/RELEASE_X86_64 x86_64

• OS: Darwin (MacOS)
• “@graphql-codegen/cli”: “2.2.0”,
• “@graphql-codegen/introspection”: “2.1.0”,
• “@graphql-codegen/typescript”: “2.2.2”,
• “@graphql-codegen/typescript-operations”: “2.1.4”,
• “@graphql-codegen/typescript-react-apollo”: “3.1.4”,
• “@graphql-codegen/typescript-resolvers”: “2.2.1”,
• NodeJS: v16.3.0

Additional context

Thanks ✌️

[ristomatti]

I played around with the different naming conventions. From the ones I tried, this issue occurs with pascalCase and camelCase but not with titleCase, upperCase or upperCaseFirst. For this particular use case using upperCaseFirst only for enums gives a good enough workaround for me.

Configuration:

generates:
  ./models/datocms/index.ts:
    plugins:
      - typescript
    config:
      namingConvention:
        enumValues: change-case-all#upperCaseFirst

Output:

export enum PageModelOrderBy {
  _createdAt_ASC = '_createdAt_ASC',
  _createdAt_DESC = '_createdAt_DESC',
  _firstPublishedAt_ASC = '_firstPublishedAt_ASC',
  _firstPublishedAt_DESC = '_firstPublishedAt_DESC',
  _isValid_ASC = '_isValid_ASC',
  _isValid_DESC = '_isValid_DESC',
  _publicationScheduledAt_ASC = '_publicationScheduledAt_ASC',
  _publicationScheduledAt_DESC = '_publicationScheduledAt_DESC',
  _publishedAt_ASC = '_publishedAt_ASC',
  _publishedAt_DESC = '_publishedAt_DESC',
  _status_ASC = '_status_ASC',
  _status_DESC = '_status_DESC',
  _unpublishingScheduledAt_ASC = '_unpublishingScheduledAt_ASC',
  _unpublishingScheduledAt_DESC = '_unpublishingScheduledAt_DESC',
  _updatedAt_ASC = '_updatedAt_ASC',
  _updatedAt_DESC = '_updatedAt_DESC',
  CreatedAt_ASC = 'createdAt_ASC',
  CreatedAt_DESC = 'createdAt_DESC',
  Id_ASC = 'id_ASC',
  Id_DESC = 'id_DESC',
  PageTitle_ASC = 'pageTitle_ASC',
  PageTitle_DESC = 'pageTitle_DESC',
  Title_ASC = 'title_ASC',
  Title_DESC = 'title_DESC',
  UpdatedAt_ASC = 'updatedAt_ASC',
  UpdatedAt_DESC = 'updatedAt_DESC'
}

Aside: I noticed some other unexpected behaviors. For example transformUnderscores did not seem to do anything with some of the naming conventions. Another one was that with this config:

    config:
      namingConvention:
        enumValues: change-case-all#titleCase

…enum names remained untouched but underscores appeared to some type names:

/** The query root for this schema */
export type Query_SiteArgs = {
  locale?: InputMaybe<SiteLocale>;
};


/** The query root for this schema */
export type QueryAllPagesArgs = {
  filter?: InputMaybe<PageModelFilter>;
  first?: InputMaybe<Scalars['IntType']>;
  locale?: InputMaybe<SiteLocale>;
  orderBy?: InputMaybe<Array<InputMaybe<PageModelOrderBy>>>;
  skip?: InputMaybe<Scalars['IntType']>;
};

[stefanoverna]

In DatoCMS createdAt is a legacy field that will be soon removed, while _createdAt is the new name. They have exactly the same meaning.

Thanks @cjpete, I’ll add a complete example here that solves the issue:

https://github.com/Tonel/typescript-type-generation-graphql-example/pull/1/files