// --strictNullChecks

interface Option1 {
	x: true;
}

interface Option2 {
	x: false | undefined;
}

type OptionUnion = Option1 | Option2;

function acceptOption1(x: Option1): void {}

function acceptOption2(x: Option2): void {}

function acceptNever(x: never): void {}

function test(anOption: OptionUnion): void {
	if (anOption.x === true) {
		acceptOption1(anOption);
	} else if (anOption.x === false || anOption.x === undefined) {
		acceptOption2(anOption);
	} else {
		acceptNever(anOption);
	}
}

// --strictNullChecks

type Option1 = true;
type Option2 = false | undefined;
type OptionUnion = Option1 | Option2;

function acceptOption1(x: Option1): void {}

function acceptOption2(x: Option2): void {}

function acceptNever(x: never): void {}

function test(anOption: OptionUnion): void {
	if (anOption === true) {
		acceptOption1(anOption);
	} else if (anOption === false || anOption === undefined) {
		acceptOption2(anOption);
	} else {
		acceptNever(anOption); // Not an error - correctly narrows to `never`
	}
}