Move internal modules to “internal” folder.

.internal/baseGet.js

@@ -0,0 +1,24 @@
+import castPath from './.internal/castPath.js';
+import toKey from './.internal/toKey.js';
+
+/**
+ * The base implementation of `get` without support for default values.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @param {Array|string} path The path of the property to get.
+ * @returns {*} Returns the resolved value.
+ */
+function baseGet(object, path) {
+  path = castPath(path, object);
+
+  let index = 0;
+  const length = path.length;
+
+  while (object != null && index < length) {
+    object = object[toKey(path[index++])];
+  }
+  return (index && index == length) ? object : undefined;
+}
+
+export default baseGet;