Allow compareMultiple to accept compare functions in addition to order strings (#3764)

.internal/compareMultiple.js

@@ -11,7 +11,7 @@ import compareAscending from './compareAscending.js'
  * @private
  * @param {Object} object The object to compare.
  * @param {Object} other The other object to compare.
- * @param {boolean[]|string[]} orders The order to sort by for each property.
+ * @param {(string|function)[]} orders The order to sort by for each property.
  * @returns {number} Returns the sort order indicator for `object`.
  */
 function compareMultiple(object, other, orders) {
@@ -22,13 +22,14 @@ function compareMultiple(object, other, orders) {
   const ordersLength = orders.length
 
   while (++index < length) {
-    const result = compareAscending(objCriteria[index], othCriteria[index])
+    var order = index < ordersLength ? orders[index] : null
+    var cmpFn = (order && typeof order === 'function') ? order: compareAscending
+    var result = cmpFn(objCriteria[index], othCriteria[index])
     if (result) {
-      if (index >= ordersLength) {
-        return result
+      if (order && typeof order !== 'function') {
+        return result * (order == 'desc' ? -1 : 1)
       }
-      const order = orders[index]
-      return result * (order == 'desc' ? -1 : 1)
+      return result
     }
   }
   // Fixes an `Array#sort` bug in the JS engine embedded in Adobe applications

orderBy.js

@@ -5,13 +5,14 @@ import baseOrderBy from './.internal/baseOrderBy.js'
  * orders of the iteratees to sort by. If `orders` is unspecified, all values
  * are sorted in ascending order. Otherwise, specify an order of "desc" for
  * descending or "asc" for ascending sort order of corresponding values.
+ * You may also specify a compare function for an order.
  *
  * @since 4.0.0
  * @category Collection
  * @param {Array|Object} collection The collection to iterate over.
  * @param {Array[]|Function[]|Object[]|string[]} [iteratees=[identity]]
  *  The iteratees to sort by.
- * @param {string[]} [orders] The sort orders of `iteratees`.
+ * @param {(string|function)[]} [orders] The sort orders of `iteratees`.
  * @returns {Array} Returns the new sorted array.
  * @see reverse
  * @example
@@ -26,6 +27,13 @@ import baseOrderBy from './.internal/baseOrderBy.js'
  * // Sort by `user` in ascending order and by `age` in descending order.
  * orderBy(users, ['user', 'age'], ['asc', 'desc'])
  * // => objects for [['barney', 36], ['barney', 34], ['fred', 48], ['fred', 40]]
+ *
+ * // Sort by `user` then by `age` using custom compare functions for each
+ * orderBy(users, ['user', 'age'], [
+ *   (a, b) => a.localeCompare(b, 'de', { sensitivity: 'base' }),
+ *   (a, b) => a - b,
+ * ])
+ *
  */
 function orderBy(collection, iteratees, orders) {
   if (collection == null) {