luhn-generator/update/node_modules/axe-core/lib/commons/table/traverse.js

A generator of numbers that passes the validation of Luhn algorithm or Luhn formula, also known as the 'modulus 10' or 'mod 10' algorithm

function traverseTable(dir, position, tableGrid, callback) {
	let result;
	const cell = tableGrid[position.y]
		? tableGrid[position.y][position.x]
		: undefined;
	if (!cell) {
		return [];
	}
	if (typeof callback === 'function') {
		result = callback(cell, position, tableGrid);
		if (result === true) {
			// abort
			return [cell];
		}
	}

	result = traverseTable(
		dir,
		{
			x: position.x + dir.x,
			y: position.y + dir.y
		},
		tableGrid,
		callback
	);
	result.unshift(cell);
	return result;
}

/**
 * Traverses a table in a given direction, passing the cell to the callback
 * @method traverse
 * @memberof axe.commons.table
 * @instance
 * @param  {Object|String} dir Direction that will be added recursively {x: 1, y: 0}, 'left';
 * @param  {Object}   startPos    x/y coordinate: {x: 0, y: 0};
 * @param  {Array}    [tablegrid]  A matrix of the table obtained using axe.commons.table.toArray (OPTIONAL)
 * @param  {Function} callback Function to which each cell will be passed
 * @return {NodeElement}       If the callback returns true, the traversal will end and the cell will be returned
 */
function traverse(dir, startPos, tableGrid, callback) {
	if (Array.isArray(startPos)) {
		callback = tableGrid;
		tableGrid = startPos;
		startPos = { x: 0, y: 0 };
	}

	if (typeof dir === 'string') {
		switch (dir) {
			case 'left':
				dir = { x: -1, y: 0 };
				break;
			case 'up':
				dir = { x: 0, y: -1 };
				break;
			case 'right':
				dir = { x: 1, y: 0 };
				break;
			case 'down':
				dir = { x: 0, y: 1 };
				break;
		}
	}

	return traverseTable(
		dir,
		{
			x: startPos.x + dir.x,
			y: startPos.y + dir.y
		},
		tableGrid,
		callback
	);
}

export default traverse;