unused local not detected on recursive functions

Bug Report

🔎 Search Terms

unused local recursive function

🕗 Version & Regression Information

v4.5.0-dev.20210807

⏯ Playground Link

Playground link with relevant code

💻 Code

export {}

//no error even though foo is never read
const foo = () => {
    foo()
}

//error: 'bar' is declared but its value is never read.(6133)
const bar = () => {}

🙁 Actual behavior

no error even though foo is never read

🙂 Expected behavior

'foo' is declared but its value is never read.(6133)

Start with the linked TypeScript Playground and reproduce the difference between the recursive foo function and the unused bar function with noUnusedLocals enabled. The payload names no source file or test, so trace the compiler's unused-local analysis from this reproduction. Done means the recursive declaration reports diagnostic 6133 without incorrectly changing the bar behavior.