getEnumDefinitions with rare "%future added value"

[artola]

For example, using github graphql schema.graphql:

"""The possible states of an issue."""
enum IssueState {
  """An issue that is still open"""
  OPEN

  """An issue that has been closed"""
  CLOSED
}

It is generated in the following type, containing an extra and rare "%future added value".

export type IssueState = "CLOSED" | "OPEN" | "%future added value";

Source code:

relay-compiler-language-typescript/src/TypeScriptGenerator.ts

Line 578 in 0a1fb9e

values.push("%future added value");

Has this extra entry in the alias some especial meaning? It seems error prone.

[sibelius]

This is to be type safe for future enum values

you could add more enum types for your graphql schema and it won't break old apps

[alloy]

For more info see eg this upstream issue facebook/relay#2351

[artola]

@sibelius @alloy thanks for your prompt reply. From my point of view, a type system makes sense when you enforce it, and this kind of entry is not needed as stated in the upstream issue.
Anyway, see the code introduced in the upstream where is possible to use the flag noFutureProofEnums to avoid them.

https://github.com/facebook/relay/blob/f54557df14f992ce175153913736eed3e2419d7c/packages/relay-compiler/language/javascript/RelayFlowGenerator.js#L535

[alloy]

Yup, that simply wasn’t ported over yet because we don’t use that option. A issue for this exists #80

[artola]

@alloy Sorry I did not see #80 ... absolutely same.

[alloy]

No worries!