feat(code-first): Use capitalized case for enums in code-first

[kasvith]

PR Checklist

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• Tests for the changes have been added (for bug fixes / features)
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PR Type

What kind of change does this PR introduce?

[ ] Bugfix
[x] Feature
[ ] Code style update (formatting, local variables)
[ ] Refactoring (no functional changes, no api changes)
[ ] Build related changes
[ ] CI related changes
[ ] Other... Please describe:

What is the current behavior?

Issue Number: #1832

What is the new behavior?

registerEnumType now contains an optional parameter called mapToUppercase(defaults to false to avoid breaking changes). This option automatically converts enum to CONST_CASE in compliance with GraphQL best practices.
It means we can use PascalCase in typescript while using CONST_CASE in GraphQL.

export enum CatType {
  PersianCat = 'persian-cat',
  MaineCoon = 'maine-coon',
  Ragdoll = 'ragdoll',
}

registerEnumType(CatType, {
  name: 'CatType',
  description: 'Distinguish cats',
  mapToUppercase: true, 
});

Would produce the following enum type in schema

"""Distinguish cats"""
enum CatType {
  PERSIAN_CAT
  MAINE_COON
  RAGDOLL
}

Does this PR introduce a breaking change?

[ ] Yes
[x] No

Other information

Since this is a norm in GraphQL world, from the next release I consider we should make mapToUppercase to true by default. So people can use natural PascalCase enum values in typescript and use CONST_CASE by default in GraphQL

[kasvith]

@kamilmysliwiec would you please take a look at this

[kasvith]

I added docs in JSDoc format for the added option. But I would also add this to nest docs once its merged

[kasvith]

I've resolved the merge conflict. Also addressed comments by @micalevisk.
Can you take a look @kamilmysliwiec ? 😃

[kasvith]

I added more test cases

[kasvith]

Hi @kamilmysliwiec would you be able to review this PR and give me a comment about the future of it :) thanks

[arnold-almeida]

This is a subtle but important feature. Agree that by default it should align with GraphQL enum best practices.

[peshkov3]

Waiting this PR

[kasvith]

Im ready to resolve conflicts once it gets proper attention

[kasvith]

@kamilmysliwiec would you be able to review this and get the approval

i can resolve the merge conflict afterwards

[kasvith]

Hi @kamilmysliwiec any news about this?

[mareksuscak]

@kasvith this option seems to be a single purpose one. Would it be better to take a key transform function so that people can use any function they want for the enum keys? toUppercase could then become the default and the feature would become a lot more useful.

[kasvith]

Hi @mareksuscak

By convention GraphQL enums are UPPER_CASE literals, i dont see a usecase to have a transformer function and make this much more complicated than it is now

https://www.apollographql.com/tutorials/side-quest-intermediate-schema-design/02-the-enum-type