Non-exported recursive type alias is inlined until it falls back to any in declarations

🔎 Search Terms

declarations recursive types

🕗 Version & Regression Information

• This is the behavior in every version I tried (before 4.4 it was either a stack overflow crash or an error on the recursive type)

⏯ Playground Link

Playground Link

💻 Code

// @declaration: true
// @filename: utils.ts 

type Recursive<T>  =  T extends Array<infer V>? Recursive<V>: T;

export const f = <T>(): Recursive<T> => { return null! } 

// @filename: index.ts 
import { f } from './utils';
export const a = f;

🙁 Actual behavior

In declarations, the type for a is printed as a: () => T extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? V extends (infer V)[] ? any : V : V : V : V : V : V : V : V : V : V : T;

🙂 Expected behavior

Recursive can't be represented without falling back to any (as seen above) so it should just be an error instead of silently to any

Additional information about the issue

Related to #55832

Riproduci l’output delle dichiarazioni dal link di Playground usando utils.ts e index.ts, concentrandoti sulla funzione generica esportata e sulla dichiarazione di a. Traccia il modo in cui l’alias Recursive non esportato viene rappresentato quando vengono emesse le dichiarazioni. Il lavoro è completato quando questo caso segnala un errore invece di produrre silenziosamente un tipo profondamente espanso che ricade su any.