insertionSort.js

function insertionSort(array, ascending){
	if(ascending === undefined)
		ascending = true;
	
	for(i = 1; i < array.length; i++){
		var key = array[i];
		var j = i - 1;
		
		while(j >= 0 && (array[j] > key === ascending)){
			array[j + 1] = array[j];
			j--;
		}
		
		array[j + 1] = key;
	}
}

there is no return statement