`x && x` should not be `NonNullable`

🔎 Search Terms

logical and, generic, NonNullable

🕗 Version & Regression Information

There has been this problem since 4.8.4 (I tried it on the playground)

⏯ Playground Link

https://www.typescriptlang.org/play/?#code/MYewdgzgLgBAZjAvDAPAFQDQD4AUAPALhjQEoksY8YAyaymAegdTV0OLMQoDlxuBXADaCAhgCNBAU3RYAUEA

💻 Code

const f = <T,>(x: T) => x && x // <T>(x: T) => NonNullable<T>

🙁 Actual behavior

Since f returns NonNullable<T>, we can make every value NonNullable, and never can be created by calling f(null).

🙂 Expected behavior

f should return T.

Additional information about the issue

No response