simple_queue_run.cjs

/**
 * CommonJS build of simpleQueueRun (converted from ESM source).
 */
const defaultOption = {
	concurrence: 5,
	interval: 0,
};

function simpleQueueRun(tasks, option) {
	return new Promise((resolve, reject) => {
		if (
			!(
				Array.isArray(tasks) &&
				tasks.every((item) => typeof item === "function")
			)
		) {
			return reject(new Error("tasks must be function array"));
		}

		if (tasks.length === 0) {
			return resolve();
		}

		const optionInner = Object.assign({}, defaultOption, option);

		let lastTaskIndex = 0;

		const execWindows = [];
		execWindows.length = optionInner.concurrence || 5;
		execWindows.fill(null);

		function pushTasks() {
			const min = Math.min(tasks.length, execWindows.length);
			for (let i = 0; i < min; i++) {
				execWindows[i] = tasks[i];
				tasks[i] = null;
			}
			lastTaskIndex = min - 1;
		}

		function runTasks() {
			execWindows.forEach((task, index) => {
				if (typeof task === "function") {
					runTask(task, index);
				}
			});
		}

		function runTask(task, index) {
			try {
				const result = task();
				if (result instanceof Promise) {
					result
						.then(() => {
							if (optionInner.interval > 0) {
								setTimeout(
									() => releaseAndCallNext(index),
									optionInner.interval,
								);
							} else {
								releaseAndCallNext(index);
							}
						})
						.catch(reject);
				} else {
					setTimeout(() => releaseAndCallNext(index), optionInner.interval);
				}
			} catch (err) {
				reject(err);
			}
		}

		function releaseAndCallNext(index) {
			if (optionInner.signal && optionInner.signal.aborted) {
				return;
			}
			execWindows[index] = null;
			const nextIndex = lastTaskIndex + 1;
			const nextTask = tasks[nextIndex];
			if (nextTask) {
				tasks[nextIndex] = null;
				lastTaskIndex = nextIndex;
				execWindows[index] = nextTask;
				runTask(nextTask, index);
			}
			const allFree = execWindows.every((item) => item === null);
			if (!nextTask && allFree) {
				tasks.length = 0;
				resolve();
			}
		}

		function onAbort() {
			reject(new Error("aborted"));
		}

		if (optionInner.signal) {
			optionInner.signal.addEventListener("abort", onAbort);
		}
		pushTasks();
		runTasks();
	});
}

module.exports = simpleQueueRun;