Generic with default type incorrectly constraint suggestions in code completion

Bug Report

When I have a function with generic constraints with a default value, IDEs' code completion only suggests the default value, despite accepting all constraint values.

https://user-images.githubusercontent.com/12190482/215557275-265d803c-9e1a-431b-896a-b0b670bbfafd.mov

🔎 Search Terms

Generic with default type

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I reviewed the FAQ for entries about Generic with default type

⏯ Playground Link

Playground link with relevant code

💻 Code

type Options = 'a' | 'b' | 'c'

type Result<T extends Options> = T extends 'a' ? true : false;

declare function func<T extends Options = 'a'>(arg?: T): Result<T>

const result = func('') // Code completion only suggests 'a'

🙁 Actual behavior

IDEs' code completion only suggests the default value.

🙂 Expected behavior

IDEs' code completion should suggest all constraint values.

Apri il TypeScript Playground collegato e riproduci il completamento per la funzione generica mostrata nell’issue. Traccia il comportamento del completamento per un generico vincolato con un tipo predefinito, quindi verifica che vengano suggeriti tutti i valori del vincolo mentre il valore predefinito rimane valido.