Bump to v4.0.0.

xorBy.js

@@ -0,0 +1,36 @@
+import arrayFilter from './internal/arrayFilter';
+import baseIteratee from './internal/baseIteratee';
+import baseXor from './internal/baseXor';
+import isArrayLikeObject from './isArrayLikeObject';
+import last from './last';
+import rest from './rest';
+
+/**
+ * This method is like `_.xor` except that it accepts `iteratee` which is
+ * invoked for each element of each `arrays` to generate the criterion by which
+ * uniqueness is computed. The iteratee is invoked with one argument: (value).
+ *
+ * @static
+ * @memberOf _
+ * @category Array
+ * @param {...Array} [arrays] The arrays to inspect.
+ * @param {Function|Object|string} [iteratee=_.identity] The iteratee invoked per element.
+ * @returns {Array} Returns the new array of values.
+ * @example
+ *
+ * _.xorBy([2.1, 1.2], [4.3, 2.4], Math.floor);
+ * // => [1.2, 4.3]
+ *
+ * // using the `_.property` iteratee shorthand
+ * _.xorBy([{ 'x': 1 }], [{ 'x': 2 }, { 'x': 1 }], 'x');
+ * // => [{ 'x': 2 }]
+ */
+var xorBy = rest(function(arrays) {
+  var iteratee = last(arrays);
+  if (isArrayLikeObject(iteratee)) {
+    iteratee = undefined;
+  }
+  return baseXor(arrayFilter(arrays, isArrayLikeObject), baseIteratee(iteratee));
+});
+
+export default xorBy;