import { EventEmitter } from "events";
import { expectType } from "tsd";

const e1 = new EventEmitter<{
  a: [string];
}>();

e1.on("a", arg => {
  expectType<string>(arg);
});
// @ts-expect-error
e1.on("qwer", _ => {});

const e2 = new EventEmitter();
e2.on("qwer", _ => {});
e2.on("asdf", arg => {
  expectType<any>(arg);
});