Move internal modules to “internal” folder.

.internal/baseOrderBy.js

@@ -0,0 +1,28 @@
+import arrayMap from './.internal/arrayMap.js';
+import baseMap from './.internal/baseMap.js';
+import baseSortBy from './.internal/baseSortBy.js';
+import compareMultiple from './.internal/compareMultiple.js';
+import identity from './identity.js';
+
+/**
+ * The base implementation of `orderBy` without param guards.
+ *
+ * @private
+ * @param {Array|Object} collection The collection to iterate over.
+ * @param {Function[]|Object[]|string[]} iteratees The iteratees to sort by.
+ * @param {string[]} orders The sort orders of `iteratees`.
+ * @returns {Array} Returns the new sorted array.
+ */
+function baseOrderBy(collection, iteratees, orders) {
+  let index = -1;
+  iteratees = iteratees.length ? iteratees : [identity];
+
+  const result = baseMap(collection, (value, key, collection) => {
+    const criteria = arrayMap(iteratees, iteratee => iteratee(value));
+    return { 'criteria': criteria, 'index': ++index, 'value': value };
+  });
+
+  return baseSortBy(result, (object, other) => compareMultiple(object, other, orders));
+}
+
+export default baseOrderBy;