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

Reproduce la salida de declaraciones del enlace de Playground usando utils.ts e index.ts, centrándote en la función genérica exportada y en la declaración de a. Rastrea cómo se representa el alias Recursive no exportado cuando se emiten las declaraciones. La tarea estará terminada cuando este caso informe de un error en lugar de producir silenciosamente un tipo profundamente expandido que termina recurriendo a any.