eslint-plugin-unicorn-x/rules/utils/cartesian-product-samples.js

More than 100 powerful ESLint rules

export default function cartesianProductSamples(
	combinations,
	length = Number.POSITIVE_INFINITY,
) {
	const total = combinations.reduce((total, {length}) => total * length, 1);

	const samples = Array.from(
		{length: Math.min(total, length)},
		(_, sampleIndex) => {
			let indexRemaining = sampleIndex;
			const combination = [];
			for (
				let combinationIndex = combinations.length - 1;
				combinationIndex >= 0;
				combinationIndex--
			) {
				const items = combinations[combinationIndex];
				const {length} = items;
				const index = indexRemaining % length;
				indexRemaining = (indexRemaining - index) / length;
				combination.unshift(items[index]);
			}

			return combination;
		},
	);

	return {
		total,
		samples,
	};
}