Literals in return positions are widened despite being typed using const type variables

[Andarist]

🔎 Search Terms

literal widening const type variable primitive

🕗 Version & Regression Information

• This is the behavior in every version I tried

⏯ Playground Link

https://www.typescriptlang.org/play?ts=5.4.0-dev.20231223#code/CYUwxgNghgTiAEAzArgOzAFwJYHtXwxAGcMAeMPE+AFQD4AKWAcwC556BKeAXlpo7bUAUEIqoqcIsggYAjDwLEM9Tjz4BtAOSIcOTQF0OQgPTH45+AD0A-KMoZ4k6RgBMCwiRVde8AAY6cABIAbwBZKAwACwA6GChUYBwAW04AX18jUwsrWzEJYmcAZnclLzV4bV1NTLMLGxEgA

💻 Code

declare function test<const T>(arg: () => T): T

const result1 = test(() => ["foo"])
//    ^? const result1: readonly ["foo"]
const result2 = test(() => `foo${Math.random()}`)
//    ^? const result2: `foo${number}`
const result3 = test(() => "foo")
//    ^? const result3: string

🙁 Actual behavior

result3 is inferred as string

🙂 Expected behavior

result3 should be inferred as "foo"

Additional information about the issue

No response