Bump to v4.0.0.

hasIn.js

@@ -0,0 +1,33 @@
+import baseHasIn from './internal/baseHasIn';
+import hasPath from './internal/hasPath';
+
+/**
+ * Checks if `path` is a direct or inherited property of `object`.
+ *
+ * @static
+ * @memberOf _
+ * @category Object
+ * @param {Object} object The object to query.
+ * @param {Array|string} path The path to check.
+ * @returns {boolean} Returns `true` if `path` exists, else `false`.
+ * @example
+ *
+ * var object = _.create({ 'a': _.create({ 'b': _.create({ 'c': 3 }) }) });
+ *
+ * _.hasIn(object, 'a');
+ * // => true
+ *
+ * _.hasIn(object, 'a.b.c');
+ * // => true
+ *
+ * _.hasIn(object, ['a', 'b', 'c']);
+ * // => true
+ *
+ * _.hasIn(object, 'b');
+ * // => false
+ */
+function hasIn(object, path) {
+  return hasPath(object, path, baseHasIn);
+}
+
+export default hasIn;