Awaiting on a Promise<never> doesn't make the rest of the block unreachable

[besfahbod]

Bug Report

🔎 Search Terms

TS2534 await

🕗 Version & Regression Information

• This is the behavior in every version I tried, and I couldn't find any related FAQ entries.

Versions tried on:

• 4.6.4 (local)
• Nightly = 4.8.0-dev.20220714) (playground)

⏯ Playground Link

https://www.typescriptlang.org/play?ts=4.8.0-dev.20220714#code/GYVwdgxgLglg9mABAWwIYGsCmARTUGr4BOAFAJQBciACkXMjAM6YA8YmAbpkQHyIDeAKEQjERPCCJJa9JpgB04gFaZoJdgHdEAUSJ1SAIgBCcegEIDZMgG5BAX0GDQkWAkQATPASiYAjOSoZBmY2Tm4+IREIBEYoDy8wQjgiILlEAF4UDBwEpNIbYTEJKXj8ROJU5lsHQVRGAE9IRGdoeCRPMsJMACYAmjpg1nYuXgFC6LBY0u9kyswMrKxcTuJyWxFUDVQYOI6ZlIG5aqA

💻 Code

function makeDetonator(): Promise<never> {
    return Promise.reject(new Error("Boom!"));
}

function detonate1(): Promise<never> {
  const detonatorPromise = makeDetonator();
  return detonatorPromise;
}

async function detonate2(): Promise<never> {
  const detonatorPromise = makeDetonator();
  await detonatorPromise;
}

🙁 Actual behavior

detonate1 has no issues, but get the following error for detonate2:

A function returning 'never' cannot have a reachable end point.

🙂 Expected behavior

detonate2 is semantically equivalent to detonate1, and there should be no such error.

It looks like the general rule that's missing is: awaiting on a Promise would make the rest of the block unreachable.

[MartinJohns]

Duplicate of #34955. Used search terms: promise never in:title