pi-ext

import assert from "node:assert/strict";
import { it } from "vitest";
import { lazy } from "../lazy.ts";

it("serializes different loads, shares a target, and continues after failure", async () => {
	let releaseFirst!: () => void;
	const firstFinished = new Promise<void>((resolve) => {
		releaseFirst = resolve;
	});
	const calls: string[] = [];
	const first = lazy(async () => {
		calls.push("first");
		await firstFinished;
		throw new Error("failed");
	});
	const second = lazy(async () => {
		calls.push("second");
		return 2;
	});
	const firstAttempt = first();
	assert.equal(first(), firstAttempt);
	const secondAttempt = second();
	await Promise.resolve();
	assert.deepEqual(calls, ["first"]);
	releaseFirst();
	await assert.rejects(firstAttempt, /failed/);
	assert.equal(await secondAttempt, 2);
	assert.deepEqual(calls, ["first", "second"]);
	await assert.rejects(first(), /failed/);
	assert.deepEqual(calls, ["first", "second", "first"]);
});