Bump to v4.1.0.

_baseMerge.js

@@ -0,0 +1,44 @@
+import Stack from './_Stack';
+import arrayEach from './_arrayEach';
+import assignMergeValue from './_assignMergeValue';
+import baseMergeDeep from './_baseMergeDeep';
+import isArray from './isArray';
+import isObject from './isObject';
+import isTypedArray from './isTypedArray';
+import keysIn from './keysIn';
+
+/**
+ * The base implementation of `_.merge` without support for multiple sources.
+ *
+ * @private
+ * @param {Object} object The destination object.
+ * @param {Object} source The source object.
+ * @param {number} srcIndex The index of `source`.
+ * @param {Function} [customizer] The function to customize merged values.
+ * @param {Object} [stack] Tracks traversed source values and their merged counterparts.
+ */
+function baseMerge(object, source, srcIndex, customizer, stack) {
+  if (object === source) {
+    return;
+  }
+  var props = (isArray(source) || isTypedArray(source)) ? undefined : keysIn(source);
+  arrayEach(props || source, function(srcValue, key) {
+    if (props) {
+      key = srcValue;
+      srcValue = source[key];
+    }
+    if (isObject(srcValue)) {
+      stack || (stack = new Stack);
+      baseMergeDeep(object, source, key, srcIndex, baseMerge, customizer, stack);
+    }
+    else {
+      var newValue = customizer ? customizer(object[key], srcValue, (key + ''), object, source, stack) : undefined;
+      if (newValue === undefined) {
+        newValue = srcValue;
+      }
+      assignMergeValue(object, key, newValue);
+    }
+  });
+}
+
+export default baseMerge;