Fix prototype pollution in _.unset and _.omit (#6065)

Prevent prototype pollution on baseUnset function by:
- Blocking "__proto__" if not an own property
- Blocking "constructor.prototype" chains (except when starting at primitive root)
- Skipping non-string keys

See: https://github.com/lodash/lodash/security/advisories/GHSA-xxjr-mmjv-4gpg

LICENSE

@@ -1,7 +1,17 @@
-Copyright 2012-2016 The Dojo Foundation <http://dojofoundation.org/>
+Copyright OpenJS Foundation and other contributors <https://openjsf.org/>
-Based on Underscore.js, copyright 2009-2016 Jeremy Ashkenas,
+
+Based on Underscore.js, copyright Jeremy Ashkenas,
 DocumentCloud and Investigative Reporters & Editors <http://underscorejs.org/>
 
+This software consists of voluntary contributions made by many
+individuals. For exact contribution history, see the revision history
+available at https://github.com/lodash/lodash
+
+The following license applies to all parts of this software except as
+documented below:
+
+====
+
 Permission is hereby granted, free of charge, to any person obtaining
 a copy of this software and associated documentation files (the
 "Software"), to deal in the Software without restriction, including
@@ -20,3 +30,18 @@ NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+
+====
+
+Copyright and related rights for sample code are waived via CC0. Sample
+code is defined as all source code displayed within the prose of the
+documentation.
+
+CC0: http://creativecommons.org/publicdomain/zero/1.0/
+
+====
+
+Files located in the node_modules and vendor directories are externally
+maintained libraries used by this software which have their own
+licenses; we recommend you read them, as their terms may differ from the
+terms above.

README.md

@@ -1,10 +1,10 @@
-# lodash-es v4.2.1
+# lodash-es v4.17.21
 
-The [lodash](https://lodash.com/) library exported as [ES](http://www.ecma-international.org/ecma-262/6.0/) modules.
+The [Lodash](https://lodash.com/) library exported as [ES](http://www.ecma-international.org/ecma-262/6.0/) modules.
 
 Generated using [lodash-cli](https://www.npmjs.com/package/lodash-cli):
-```bash
+```shell
 $ lodash modularize exports=es -o ./
 ```
 
-See the [package source](https://github.com/lodash/lodash/tree/4.2.1-es) for more details.
+See the [package source](https://github.com/lodash/lodash/tree/4.17.21-es) for more details.

_DataView.js

@@ -0,0 +1,7 @@
+import getNative from './_getNative.js';
+import root from './_root.js';
+
+/* Built-in method references that are verified to be native. */
+var DataView = getNative(root, 'DataView');
+
+export default DataView;

_Hash.js

@@ -1,17 +1,32 @@
-import nativeCreate from './_nativeCreate';
+import hashClear from './_hashClear.js';
-
+import hashDelete from './_hashDelete.js';
-/** Used for built-in method references. */
+import hashGet from './_hashGet.js';
-var objectProto = Object.prototype;
+import hashHas from './_hashHas.js';
+import hashSet from './_hashSet.js';
 
 /**
- * Creates an hash object.
+ * Creates a hash object.
  *
  * @private
- * @returns {Object} Returns the new hash object.
+ * @constructor
+ * @param {Array} [entries] The key-value pairs to cache.
  */
-function Hash() {}
+function Hash(entries) {
+  var index = -1,
+      length = entries == null ? 0 : entries.length;
 
-// Avoid inheriting from `Object.prototype` when possible.
+  this.clear();
-Hash.prototype = nativeCreate ? nativeCreate(null) : objectProto;
+  while (++index < length) {
+    var entry = entries[index];
+    this.set(entry[0], entry[1]);
+  }
+}
+
+// Add methods to `Hash`.
+Hash.prototype.clear = hashClear;
+Hash.prototype['delete'] = hashDelete;
+Hash.prototype.get = hashGet;
+Hash.prototype.has = hashHas;
+Hash.prototype.set = hashSet;
 
 export default Hash;

_LazyWrapper.js

@@ -1,5 +1,5 @@
-import baseCreate from './_baseCreate';
+import baseCreate from './_baseCreate.js';
-import baseLodash from './_baseLodash';
+import baseLodash from './_baseLodash.js';
 
 /** Used as references for the maximum length and index of an array. */
 var MAX_ARRAY_LENGTH = 4294967295;
@@ -8,6 +8,7 @@ var MAX_ARRAY_LENGTH = 4294967295;
  * Creates a lazy wrapper object which wraps `value` to enable lazy evaluation.
  *
  * @private
+ * @constructor
  * @param {*} value The value to wrap.
  */
 function LazyWrapper(value) {
@@ -20,6 +21,7 @@ function LazyWrapper(value) {
   this.__views__ = [];
 }
 
+// Ensure `LazyWrapper` is an instance of `baseLodash`.
 LazyWrapper.prototype = baseCreate(baseLodash.prototype);
 LazyWrapper.prototype.constructor = LazyWrapper;
 

_ListCache.js

@@ -0,0 +1,32 @@
+import listCacheClear from './_listCacheClear.js';
+import listCacheDelete from './_listCacheDelete.js';
+import listCacheGet from './_listCacheGet.js';
+import listCacheHas from './_listCacheHas.js';
+import listCacheSet from './_listCacheSet.js';
+
+/**
+ * Creates an list cache object.
+ *
+ * @private
+ * @constructor
+ * @param {Array} [entries] The key-value pairs to cache.
+ */
+function ListCache(entries) {
+  var index = -1,
+      length = entries == null ? 0 : entries.length;
+
+  this.clear();
+  while (++index < length) {
+    var entry = entries[index];
+    this.set(entry[0], entry[1]);
+  }
+}
+
+// Add methods to `ListCache`.
+ListCache.prototype.clear = listCacheClear;
+ListCache.prototype['delete'] = listCacheDelete;
+ListCache.prototype.get = listCacheGet;
+ListCache.prototype.has = listCacheHas;
+ListCache.prototype.set = listCacheSet;
+
+export default ListCache;

_LodashWrapper.js

@@ -1,12 +1,12 @@
-import baseCreate from './_baseCreate';
+import baseCreate from './_baseCreate.js';
-import baseLodash from './_baseLodash';
+import baseLodash from './_baseLodash.js';
 
 /**
  * The base constructor for creating `lodash` wrapper objects.
  *
  * @private
  * @param {*} value The value to wrap.
- * @param {boolean} [chainAll] Enable chaining for all wrapper methods.
+ * @param {boolean} [chainAll] Enable explicit method chain sequences.
  */
 function LodashWrapper(value, chainAll) {
   this.__wrapped__ = value;

_Map.js

@@ -1,5 +1,5 @@
-import getNative from './_getNative';
+import getNative from './_getNative.js';
-import root from './_root';
+import root from './_root.js';
 
 /* Built-in method references that are verified to be native. */
 var Map = getNative(root, 'Map');

_MapCache.js

@@ -1,31 +1,32 @@
-import mapClear from './_mapClear';
+import mapCacheClear from './_mapCacheClear.js';
-import mapDelete from './_mapDelete';
+import mapCacheDelete from './_mapCacheDelete.js';
-import mapGet from './_mapGet';
+import mapCacheGet from './_mapCacheGet.js';
-import mapHas from './_mapHas';
+import mapCacheHas from './_mapCacheHas.js';
-import mapSet from './_mapSet';
+import mapCacheSet from './_mapCacheSet.js';
 
 /**
  * Creates a map cache object to store key-value pairs.
  *
  * @private
- * @param {Array} [values] The values to cache.
+ * @constructor
+ * @param {Array} [entries] The key-value pairs to cache.
  */
-function MapCache(values) {
+function MapCache(entries) {
   var index = -1,
-      length = values ? values.length : 0;
+      length = entries == null ? 0 : entries.length;
 
   this.clear();
   while (++index < length) {
-    var entry = values[index];
+    var entry = entries[index];
     this.set(entry[0], entry[1]);
   }
 }
 
-// Add functions to the `MapCache`.
+// Add methods to `MapCache`.
-MapCache.prototype.clear = mapClear;
+MapCache.prototype.clear = mapCacheClear;
-MapCache.prototype['delete'] = mapDelete;
+MapCache.prototype['delete'] = mapCacheDelete;
-MapCache.prototype.get = mapGet;
+MapCache.prototype.get = mapCacheGet;
-MapCache.prototype.has = mapHas;
+MapCache.prototype.has = mapCacheHas;
-MapCache.prototype.set = mapSet;
+MapCache.prototype.set = mapCacheSet;
 
 export default MapCache;

_Promise.js

@@ -0,0 +1,7 @@
+import getNative from './_getNative.js';
+import root from './_root.js';
+
+/* Built-in method references that are verified to be native. */
+var Promise = getNative(root, 'Promise');
+
+export default Promise;

_Reflect.js

@@ -1,6 +0,0 @@
-import root from './_root';
-
-/** Built-in value references. */
-var Reflect = root.Reflect;
-
-export default Reflect;

_Set.js

@@ -1,5 +1,5 @@
-import getNative from './_getNative';
+import getNative from './_getNative.js';
-import root from './_root';
+import root from './_root.js';
 
 /* Built-in method references that are verified to be native. */
 var Set = getNative(root, 'Set');

_SetCache.js

@@ -1,24 +1,27 @@
-import MapCache from './_MapCache';
+import MapCache from './_MapCache.js';
-import cachePush from './_cachePush';
+import setCacheAdd from './_setCacheAdd.js';
+import setCacheHas from './_setCacheHas.js';
 
 /**
  *
- * Creates a set cache object to store unique values.
+ * Creates an array cache object to store unique values.
  *
  * @private
+ * @constructor
  * @param {Array} [values] The values to cache.
  */
 function SetCache(values) {
   var index = -1,
-      length = values ? values.length : 0;
+      length = values == null ? 0 : values.length;
 
   this.__data__ = new MapCache;
   while (++index < length) {
-    this.push(values[index]);
+    this.add(values[index]);
   }
 }
 
-// Add functions to the `SetCache`.
+// Add methods to `SetCache`.
-SetCache.prototype.push = cachePush;
+SetCache.prototype.add = SetCache.prototype.push = setCacheAdd;
+SetCache.prototype.has = setCacheHas;
 
 export default SetCache;

_Stack.js

@@ -1,27 +1,23 @@
-import stackClear from './_stackClear';
+import ListCache from './_ListCache.js';
-import stackDelete from './_stackDelete';
+import stackClear from './_stackClear.js';
-import stackGet from './_stackGet';
+import stackDelete from './_stackDelete.js';
-import stackHas from './_stackHas';
+import stackGet from './_stackGet.js';
-import stackSet from './_stackSet';
+import stackHas from './_stackHas.js';
+import stackSet from './_stackSet.js';
 
 /**
  * Creates a stack cache object to store key-value pairs.
  *
  * @private
- * @param {Array} [values] The values to cache.
+ * @constructor
+ * @param {Array} [entries] The key-value pairs to cache.
  */
-function Stack(values) {
+function Stack(entries) {
-  var index = -1,
+  var data = this.__data__ = new ListCache(entries);
-      length = values ? values.length : 0;
+  this.size = data.size;
-
-  this.clear();
-  while (++index < length) {
-    var entry = values[index];
-    this.set(entry[0], entry[1]);
-  }
 }
 
-// Add functions to the `Stack` cache.
+// Add methods to `Stack`.
 Stack.prototype.clear = stackClear;
 Stack.prototype['delete'] = stackDelete;
 Stack.prototype.get = stackGet;

_Symbol.js

@@ -1,4 +1,4 @@
-import root from './_root';
+import root from './_root.js';
 
 /** Built-in value references. */
 var Symbol = root.Symbol;

_Uint8Array.js

@@ -1,4 +1,4 @@
-import root from './_root';
+import root from './_root.js';
 
 /** Built-in value references. */
 var Uint8Array = root.Uint8Array;

_WeakMap.js

@@ -1,5 +1,5 @@
-import getNative from './_getNative';
+import getNative from './_getNative.js';
-import root from './_root';
+import root from './_root.js';
 
 /* Built-in method references that are verified to be native. */
 var WeakMap = getNative(root, 'WeakMap');

_addMapEntry.js

@@ -7,6 +7,7 @@
  * @returns {Object} Returns `map`.
  */
 function addMapEntry(map, pair) {
+  // Don't return `map.set` because it's not chainable in IE 11.
   map.set(pair[0], pair[1]);
   return map;
 }

_addSetEntry.js

@@ -7,6 +7,7 @@
  * @returns {Object} Returns `set`.
  */
 function addSetEntry(set, value) {
+  // Don't return `set.add` because it's not chainable in IE 11.
   set.add(value);
   return set;
 }

_apply.js

@@ -5,12 +5,11 @@
  * @private
  * @param {Function} func The function to invoke.
  * @param {*} thisArg The `this` binding of `func`.
- * @param {...*} args The arguments to invoke `func` with.
+ * @param {Array} args The arguments to invoke `func` with.
  * @returns {*} Returns the result of `func`.
  */
 function apply(func, thisArg, args) {
-  var length = args.length;
+  switch (args.length) {
-  switch (length) {
     case 0: return func.call(thisArg);
     case 1: return func.call(thisArg, args[0]);
     case 2: return func.call(thisArg, args[0], args[1]);

_arrayAggregator.js

@@ -2,7 +2,7 @@
  * A specialized version of `baseAggregator` for arrays.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} setter The function to set `accumulator` values.
  * @param {Function} iteratee The iteratee to transform keys.
  * @param {Object} accumulator The initial aggregated object.
@@ -10,7 +10,7 @@
  */
 function arrayAggregator(array, setter, iteratee, accumulator) {
   var index = -1,
-      length = array.length;
+      length = array == null ? 0 : array.length;
 
   while (++index < length) {
     var value = array[index];

_arrayConcat.js

@@ -1,25 +0,0 @@
-/**
- * Creates a new array concatenating `array` with `other`.
- *
- * @private
- * @param {Array} array The first array to concatenate.
- * @param {Array} other The second array to concatenate.
- * @returns {Array} Returns the new concatenated array.
- */
-function arrayConcat(array, other) {
-  var index = -1,
-      length = array.length,
-      othIndex = -1,
-      othLength = other.length,
-      result = Array(length + othLength);
-
-  while (++index < length) {
-    result[index] = array[index];
-  }
-  while (++othIndex < othLength) {
-    result[index++] = other[othIndex];
-  }
-  return result;
-}
-
-export default arrayConcat;

_arrayEach.js

@@ -3,13 +3,13 @@
  * iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} iteratee The function invoked per iteration.
  * @returns {Array} Returns `array`.
  */
 function arrayEach(array, iteratee) {
   var index = -1,
-      length = array.length;
+      length = array == null ? 0 : array.length;
 
   while (++index < length) {
     if (iteratee(array[index], index, array) === false) {

_arrayEachRight.js

@@ -3,12 +3,12 @@
  * iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} iteratee The function invoked per iteration.
  * @returns {Array} Returns `array`.
  */
 function arrayEachRight(array, iteratee) {
-  var length = array.length;
+  var length = array == null ? 0 : array.length;
 
   while (length--) {
     if (iteratee(array[length], length, array) === false) {

_arrayEvery.js

@@ -3,13 +3,14 @@
  * iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} predicate The function invoked per iteration.
- * @returns {boolean} Returns `true` if all elements pass the predicate check, else `false`.
+ * @returns {boolean} Returns `true` if all elements pass the predicate check,
+ *  else `false`.
  */
 function arrayEvery(array, predicate) {
   var index = -1,
-      length = array.length;
+      length = array == null ? 0 : array.length;
 
   while (++index < length) {
     if (!predicate(array[index], index, array)) {

_arrayFilter.js

@@ -3,20 +3,20 @@
  * iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} predicate The function invoked per iteration.
  * @returns {Array} Returns the new filtered array.
  */
 function arrayFilter(array, predicate) {
   var index = -1,
-      length = array.length,
+      length = array == null ? 0 : array.length,
-      resIndex = -1,
+      resIndex = 0,
       result = [];
 
   while (++index < length) {
     var value = array[index];
     if (predicate(value, index, array)) {
-      result[++resIndex] = value;
+      result[resIndex++] = value;
     }
   }
   return result;

_arrayIncludes.js

@@ -1,16 +1,17 @@
-import baseIndexOf from './_baseIndexOf';
+import baseIndexOf from './_baseIndexOf.js';
 
 /**
  * A specialized version of `_.includes` for arrays without support for
  * specifying an index to search from.
  *
  * @private
- * @param {Array} array The array to search.
+ * @param {Array} [array] The array to inspect.
  * @param {*} target The value to search for.
  * @returns {boolean} Returns `true` if `target` is found, else `false`.
  */
 function arrayIncludes(array, value) {
-  return !!array.length && baseIndexOf(array, value, 0) > -1;
+  var length = array == null ? 0 : array.length;
+  return !!length && baseIndexOf(array, value, 0) > -1;
 }
 
 export default arrayIncludes;

_arrayIncludesWith.js

@@ -1,16 +1,15 @@
 /**
- * A specialized version of `_.includesWith` for arrays without support for
+ * This function is like `arrayIncludes` except that it accepts a comparator.
- * specifying an index to search from.
  *
  * @private
- * @param {Array} array The array to search.
+ * @param {Array} [array] The array to inspect.
  * @param {*} target The value to search for.
  * @param {Function} comparator The comparator invoked per element.
  * @returns {boolean} Returns `true` if `target` is found, else `false`.
  */
 function arrayIncludesWith(array, value, comparator) {
   var index = -1,
-      length = array.length;
+      length = array == null ? 0 : array.length;
 
   while (++index < length) {
     if (comparator(value, array[index])) {

_arrayLikeKeys.js

@@ -0,0 +1,49 @@
+import baseTimes from './_baseTimes.js';
+import isArguments from './isArguments.js';
+import isArray from './isArray.js';
+import isBuffer from './isBuffer.js';
+import isIndex from './_isIndex.js';
+import isTypedArray from './isTypedArray.js';
+
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
+
+/**
+ * Creates an array of the enumerable property names of the array-like `value`.
+ *
+ * @private
+ * @param {*} value The value to query.
+ * @param {boolean} inherited Specify returning inherited property names.
+ * @returns {Array} Returns the array of property names.
+ */
+function arrayLikeKeys(value, inherited) {
+  var isArr = isArray(value),
+      isArg = !isArr && isArguments(value),
+      isBuff = !isArr && !isArg && isBuffer(value),
+      isType = !isArr && !isArg && !isBuff && isTypedArray(value),
+      skipIndexes = isArr || isArg || isBuff || isType,
+      result = skipIndexes ? baseTimes(value.length, String) : [],
+      length = result.length;
+
+  for (var key in value) {
+    if ((inherited || hasOwnProperty.call(value, key)) &&
+        !(skipIndexes && (
+           // Safari 9 has enumerable `arguments.length` in strict mode.
+           key == 'length' ||
+           // Node.js 0.10 has enumerable non-index properties on buffers.
+           (isBuff && (key == 'offset' || key == 'parent')) ||
+           // PhantomJS 2 has enumerable non-index properties on typed arrays.
+           (isType && (key == 'buffer' || key == 'byteLength' || key == 'byteOffset')) ||
+           // Skip index properties.
+           isIndex(key, length)
+        ))) {
+      result.push(key);
+    }
+  }
+  return result;
+}
+
+export default arrayLikeKeys;

_arrayMap.js

@@ -3,13 +3,13 @@
  * shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} iteratee The function invoked per iteration.
  * @returns {Array} Returns the new mapped array.
  */
 function arrayMap(array, iteratee) {
   var index = -1,
-      length = array.length,
+      length = array == null ? 0 : array.length,
       result = Array(length);
 
   while (++index < length) {

_arrayReduce.js

@@ -3,15 +3,16 @@
  * iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} iteratee The function invoked per iteration.
  * @param {*} [accumulator] The initial value.
- * @param {boolean} [initAccum] Specify using the first element of `array` as the initial value.
+ * @param {boolean} [initAccum] Specify using the first element of `array` as
+ *  the initial value.
  * @returns {*} Returns the accumulated value.
  */
 function arrayReduce(array, iteratee, accumulator, initAccum) {
   var index = -1,
-      length = array.length;
+      length = array == null ? 0 : array.length;
 
   if (initAccum && length) {
     accumulator = array[++index];

_arrayReduceRight.js

@@ -3,14 +3,15 @@
  * iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} iteratee The function invoked per iteration.
  * @param {*} [accumulator] The initial value.
- * @param {boolean} [initAccum] Specify using the last element of `array` as the initial value.
+ * @param {boolean} [initAccum] Specify using the last element of `array` as
+ *  the initial value.
  * @returns {*} Returns the accumulated value.
  */
 function arrayReduceRight(array, iteratee, accumulator, initAccum) {
-  var length = array.length;
+  var length = array == null ? 0 : array.length;
   if (initAccum && length) {
     accumulator = array[--length];
   }

_arraySample.js

@@ -0,0 +1,15 @@
+import baseRandom from './_baseRandom.js';
+
+/**
+ * A specialized version of `_.sample` for arrays.
+ *
+ * @private
+ * @param {Array} array The array to sample.
+ * @returns {*} Returns the random element.
+ */
+function arraySample(array) {
+  var length = array.length;
+  return length ? array[baseRandom(0, length - 1)] : undefined;
+}
+
+export default arraySample;

_arraySampleSize.js

@@ -0,0 +1,17 @@
+import baseClamp from './_baseClamp.js';
+import copyArray from './_copyArray.js';
+import shuffleSelf from './_shuffleSelf.js';
+
+/**
+ * A specialized version of `_.sampleSize` for arrays.
+ *
+ * @private
+ * @param {Array} array The array to sample.
+ * @param {number} n The number of elements to sample.
+ * @returns {Array} Returns the random elements.
+ */
+function arraySampleSize(array, n) {
+  return shuffleSelf(copyArray(array), baseClamp(n, 0, array.length));
+}
+
+export default arraySampleSize;

_arrayShuffle.js

@@ -0,0 +1,15 @@
+import copyArray from './_copyArray.js';
+import shuffleSelf from './_shuffleSelf.js';
+
+/**
+ * A specialized version of `_.shuffle` for arrays.
+ *
+ * @private
+ * @param {Array} array The array to shuffle.
+ * @returns {Array} Returns the new shuffled array.
+ */
+function arrayShuffle(array) {
+  return shuffleSelf(copyArray(array));
+}
+
+export default arrayShuffle;

_arraySome.js

@@ -3,13 +3,14 @@
  * shorthands.
  *
  * @private
- * @param {Array} array The array to iterate over.
+ * @param {Array} [array] The array to iterate over.
  * @param {Function} predicate The function invoked per iteration.
- * @returns {boolean} Returns `true` if any element passes the predicate check, else `false`.
+ * @returns {boolean} Returns `true` if any element passes the predicate check,
+ *  else `false`.
  */
 function arraySome(array, predicate) {
   var index = -1,
-      length = array.length;
+      length = array == null ? 0 : array.length;
 
   while (++index < length) {
     if (predicate(array[index], index, array)) {

_asciiSize.js

@@ -0,0 +1,12 @@
+import baseProperty from './_baseProperty.js';
+
+/**
+ * Gets the size of an ASCII `string`.
+ *
+ * @private
+ * @param {string} string The string inspect.
+ * @returns {number} Returns the string size.
+ */
+var asciiSize = baseProperty('length');
+
+export default asciiSize;

_asciiToArray.js

@@ -0,0 +1,12 @@
+/**
+ * Converts an ASCII `string` to an array.
+ *
+ * @private
+ * @param {string} string The string to convert.
+ * @returns {Array} Returns the converted array.
+ */
+function asciiToArray(string) {
+  return string.split('');
+}
+
+export default asciiToArray;

_asciiWords.js

@@ -0,0 +1,15 @@
+/** Used to match words composed of alphanumeric characters. */
+var reAsciiWord = /[^\x00-\x2f\x3a-\x40\x5b-\x60\x7b-\x7f]+/g;
+
+/**
+ * Splits an ASCII `string` into an array of its words.
+ *
+ * @private
+ * @param {string} The string to inspect.
+ * @returns {Array} Returns the words of `string`.
+ */
+function asciiWords(string) {
+  return string.match(reAsciiWord) || [];
+}
+
+export default asciiWords;

_assignMergeValue.js

@@ -1,7 +1,9 @@
-import eq from './eq';
+import baseAssignValue from './_baseAssignValue.js';
+import eq from './eq.js';
 
 /**
- * This function is like `assignValue` except that it doesn't assign `undefined` values.
+ * This function is like `assignValue` except that it doesn't assign
+ * `undefined` values.
  *
  * @private
  * @param {Object} object The object to modify.
@@ -10,8 +12,8 @@ import eq from './eq';
  */
 function assignMergeValue(object, key, value) {
   if ((value !== undefined && !eq(object[key], value)) ||
-      (typeof key == 'number' && value === undefined && !(key in object))) {
+      (value === undefined && !(key in object))) {
-    object[key] = value;
+    baseAssignValue(object, key, value);
   }
 }
 

_assignValue.js

@@ -1,4 +1,5 @@
-import eq from './eq';
+import baseAssignValue from './_baseAssignValue.js';
+import eq from './eq.js';
 
 /** Used for built-in method references. */
 var objectProto = Object.prototype;
@@ -8,7 +9,7 @@ var hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
  * Assigns `value` to `key` of `object` if the existing value is not equivalent
- * using [`SameValueZero`](http://ecma-international.org/ecma-262/6.0/#sec-samevaluezero)
+ * using [`SameValueZero`](http://ecma-international.org/ecma-262/7.0/#sec-samevaluezero)
  * for equality comparisons.
  *
  * @private
@@ -18,10 +19,9 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  */
 function assignValue(object, key, value) {
   var objValue = object[key];
-  if ((!eq(objValue, value) ||
+  if (!(hasOwnProperty.call(object, key) && eq(objValue, value)) ||
-        (eq(objValue, objectProto[key]) && !hasOwnProperty.call(object, key))) ||
       (value === undefined && !(key in object))) {
-    object[key] = value;
+    baseAssignValue(object, key, value);
   }
 }
 

_assocGet.js

@@ -1,16 +0,0 @@
-import assocIndexOf from './_assocIndexOf';
-
-/**
- * Gets the associative array value for `key`.
- *
- * @private
- * @param {Array} array The array to query.
- * @param {string} key The key of the value to get.
- * @returns {*} Returns the entry value.
- */
-function assocGet(array, key) {
-  var index = assocIndexOf(array, key);
-  return index < 0 ? undefined : array[index][1];
-}
-
-export default assocGet;

_assocHas.js

@@ -1,15 +0,0 @@
-import assocIndexOf from './_assocIndexOf';
-
-/**
- * Checks if an associative array value for `key` exists.
- *
- * @private
- * @param {Array} array The array to query.
- * @param {string} key The key of the entry to check.
- * @returns {boolean} Returns `true` if an entry for `key` exists, else `false`.
- */
-function assocHas(array, key) {
-  return assocIndexOf(array, key) > -1;
-}
-
-export default assocHas;

_assocIndexOf.js

@@ -1,11 +1,10 @@
-import eq from './eq';
+import eq from './eq.js';
 
 /**
- * Gets the index at which the first occurrence of `key` is found in `array`
+ * Gets the index at which the `key` is found in `array` of key-value pairs.
- * of key-value pairs.
  *
  * @private
- * @param {Array} array The array to search.
+ * @param {Array} array The array to inspect.
  * @param {*} key The key to search for.
  * @returns {number} Returns the index of the matched value, else `-1`.
  */

_assocSet.js

@@ -1,20 +0,0 @@
-import assocIndexOf from './_assocIndexOf';
-
-/**
- * Sets the associative array `key` to `value`.
- *
- * @private
- * @param {Array} array The array to modify.
- * @param {string} key The key of the value to set.
- * @param {*} value The value to set.
- */
-function assocSet(array, key, value) {
-  var index = assocIndexOf(array, key);
-  if (index < 0) {
-    array.push([key, value]);
-  } else {
-    array[index][1] = value;
-  }
-}
-
-export default assocSet;

_baseAggregator.js

@@ -1,4 +1,4 @@
-import baseEach from './_baseEach';
+import baseEach from './_baseEach.js';
 
 /**
  * Aggregates elements of `collection` on `accumulator` with keys transformed

_baseAssign.js

@@ -1,5 +1,5 @@
-import copyObject from './_copyObject';
+import copyObject from './_copyObject.js';
-import keys from './keys';
+import keys from './keys.js';
 
 /**
  * The base implementation of `_.assign` without support for multiple sources

_baseAssignIn.js

@@ -0,0 +1,17 @@
+import copyObject from './_copyObject.js';
+import keysIn from './keysIn.js';
+
+/**
+ * The base implementation of `_.assignIn` without support for multiple sources
+ * or `customizer` functions.
+ *
+ * @private
+ * @param {Object} object The destination object.
+ * @param {Object} source The source object.
+ * @returns {Object} Returns `object`.
+ */
+function baseAssignIn(object, source) {
+  return object && copyObject(source, keysIn(source), object);
+}
+
+export default baseAssignIn;

_baseAssignValue.js

@@ -0,0 +1,25 @@
+import defineProperty from './_defineProperty.js';
+
+/**
+ * The base implementation of `assignValue` and `assignMergeValue` without
+ * value checks.
+ *
+ * @private
+ * @param {Object} object The object to modify.
+ * @param {string} key The key of the property to assign.
+ * @param {*} value The value to assign.
+ */
+function baseAssignValue(object, key, value) {
+  if (key == '__proto__' && defineProperty) {
+    defineProperty(object, key, {
+      'configurable': true,
+      'enumerable': true,
+      'value': value,
+      'writable': true
+    });
+  } else {
+    object[key] = value;
+  }
+}
+
+export default baseAssignValue;

_baseAt.js

@@ -1,21 +1,21 @@
-import get from './get';
+import get from './get.js';
 
 /**
  * The base implementation of `_.at` without support for individual paths.
  *
  * @private
  * @param {Object} object The object to iterate over.
- * @param {string[]} paths The property paths of elements to pick.
+ * @param {string[]} paths The property paths to pick.
- * @returns {Array} Returns the new array of picked elements.
+ * @returns {Array} Returns the picked elements.
  */
 function baseAt(object, paths) {
   var index = -1,
-      isNil = object == null,
       length = paths.length,
-      result = Array(length);
+      result = Array(length),
+      skip = object == null;
 
   while (++index < length) {
-    result[index] = isNil ? undefined : get(object, paths[index]);
+    result[index] = skip ? undefined : get(object, paths[index]);
   }
   return result;
 }

_baseClamp.js

@@ -1,5 +1,5 @@
 /**
- * The base implementation of `_.clamp` which doesn't coerce arguments to numbers.
+ * The base implementation of `_.clamp` which doesn't coerce arguments.
  *
  * @private
  * @param {number} number The number to clamp.

_baseClone.js

@@ -1,17 +1,30 @@
-import Stack from './_Stack';
+import Stack from './_Stack.js';
-import arrayEach from './_arrayEach';
+import arrayEach from './_arrayEach.js';
-import assignValue from './_assignValue';
+import assignValue from './_assignValue.js';
-import baseAssign from './_baseAssign';
+import baseAssign from './_baseAssign.js';
-import baseForOwn from './_baseForOwn';
+import baseAssignIn from './_baseAssignIn.js';
-import copyArray from './_copyArray';
+import cloneBuffer from './_cloneBuffer.js';
-import copySymbols from './_copySymbols';
+import copyArray from './_copyArray.js';
-import getTag from './_getTag';
+import copySymbols from './_copySymbols.js';
-import initCloneArray from './_initCloneArray';
+import copySymbolsIn from './_copySymbolsIn.js';
-import initCloneByTag from './_initCloneByTag';
+import getAllKeys from './_getAllKeys.js';
-import initCloneObject from './_initCloneObject';
+import getAllKeysIn from './_getAllKeysIn.js';
-import isArray from './isArray';
+import getTag from './_getTag.js';
-import isHostObject from './_isHostObject';
+import initCloneArray from './_initCloneArray.js';
-import isObject from './isObject';
+import initCloneByTag from './_initCloneByTag.js';
+import initCloneObject from './_initCloneObject.js';
+import isArray from './isArray.js';
+import isBuffer from './isBuffer.js';
+import isMap from './isMap.js';
+import isObject from './isObject.js';
+import isSet from './isSet.js';
+import keys from './keys.js';
+import keysIn from './keysIn.js';
+
+/** Used to compose bitmasks for cloning. */
+var CLONE_DEEP_FLAG = 1,
+    CLONE_FLAT_FLAG = 2,
+    CLONE_SYMBOLS_FLAG = 4;
 
 /** `Object#toString` result references. */
 var argsTag = '[object Arguments]',
@@ -31,6 +44,7 @@ var argsTag = '[object Arguments]',
     weakMapTag = '[object WeakMap]';
 
 var arrayBufferTag = '[object ArrayBuffer]',
+    dataViewTag = '[object DataView]',
     float32Tag = '[object Float32Array]',
     float64Tag = '[object Float64Array]',
     int8Tag = '[object Int8Array]',
@@ -44,16 +58,16 @@ var arrayBufferTag = '[object ArrayBuffer]',
 /** Used to identify `toStringTag` values supported by `_.clone`. */
 var cloneableTags = {};
 cloneableTags[argsTag] = cloneableTags[arrayTag] =
-cloneableTags[arrayBufferTag] = cloneableTags[boolTag] =
+cloneableTags[arrayBufferTag] = cloneableTags[dataViewTag] =
-cloneableTags[dateTag] = cloneableTags[float32Tag] =
+cloneableTags[boolTag] = cloneableTags[dateTag] =
-cloneableTags[float64Tag] = cloneableTags[int8Tag] =
+cloneableTags[float32Tag] = cloneableTags[float64Tag] =
-cloneableTags[int16Tag] = cloneableTags[int32Tag] =
+cloneableTags[int8Tag] = cloneableTags[int16Tag] =
-cloneableTags[mapTag] = cloneableTags[numberTag] =
+cloneableTags[int32Tag] = cloneableTags[mapTag] =
-cloneableTags[objectTag] = cloneableTags[regexpTag] =
+cloneableTags[numberTag] = cloneableTags[objectTag] =
-cloneableTags[setTag] = cloneableTags[stringTag] =
+cloneableTags[regexpTag] = cloneableTags[setTag] =
-cloneableTags[symbolTag] = cloneableTags[uint8Tag] =
+cloneableTags[stringTag] = cloneableTags[symbolTag] =
-cloneableTags[uint8ClampedTag] = cloneableTags[uint16Tag] =
+cloneableTags[uint8Tag] = cloneableTags[uint8ClampedTag] =
-cloneableTags[uint32Tag] = true;
+cloneableTags[uint16Tag] = cloneableTags[uint32Tag] = true;
 cloneableTags[errorTag] = cloneableTags[funcTag] =
 cloneableTags[weakMapTag] = false;
 
@@ -63,15 +77,22 @@ cloneableTags[weakMapTag] = false;
  *
  * @private
  * @param {*} value The value to clone.
- * @param {boolean} [isDeep] Specify a deep clone.
+ * @param {boolean} bitmask The bitmask flags.
+ *  1 - Deep clone
+ *  2 - Flatten inherited properties
+ *  4 - Clone symbols
  * @param {Function} [customizer] The function to customize cloning.
  * @param {string} [key] The key of `value`.
  * @param {Object} [object] The parent object of `value`.
  * @param {Object} [stack] Tracks traversed objects and their clone counterparts.
  * @returns {*} Returns the cloned value.
  */
-function baseClone(value, isDeep, customizer, key, object, stack) {
+function baseClone(value, bitmask, customizer, key, object, stack) {
-  var result;
+  var result,
+      isDeep = bitmask & CLONE_DEEP_FLAG,
+      isFlat = bitmask & CLONE_FLAT_FLAG,
+      isFull = bitmask & CLONE_SYMBOLS_FLAG;
+
   if (customizer) {
     result = object ? customizer(value, key, object, stack) : customizer(value);
   }
@@ -91,18 +112,21 @@ function baseClone(value, isDeep, customizer, key, object, stack) {
     var tag = getTag(value),
         isFunc = tag == funcTag || tag == genTag;
 
+    if (isBuffer(value)) {
+      return cloneBuffer(value, isDeep);
+    }
     if (tag == objectTag || tag == argsTag || (isFunc && !object)) {
-      if (isHostObject(value)) {
+      result = (isFlat || isFunc) ? {} : initCloneObject(value);
-        return object ? value : {};
-      }
-      result = initCloneObject(isFunc ? {} : value);
       if (!isDeep) {
-        return copySymbols(value, baseAssign(result, value));
+        return isFlat
+          ? copySymbolsIn(value, baseAssignIn(result, value))
+          : copySymbols(value, baseAssign(result, value));
       }
     } else {
-      return cloneableTags[tag]
+      if (!cloneableTags[tag]) {
-        ? initCloneByTag(value, tag, isDeep)
+        return object ? value : {};
-        : (object ? value : {});
+      }
+      result = initCloneByTag(value, tag, isDeep);
     }
   }
   // Check for circular references and return its corresponding clone.
@@ -113,11 +137,30 @@ function baseClone(value, isDeep, customizer, key, object, stack) {
   }
   stack.set(value, result);
 
-  // Recursively populate clone (susceptible to call stack limits).
+  if (isSet(value)) {
-  (isArr ? arrayEach : baseForOwn)(value, function(subValue, key) {
+    value.forEach(function(subValue) {
-    assignValue(result, key, baseClone(subValue, isDeep, customizer, key, value, stack));
+      result.add(baseClone(subValue, bitmask, customizer, subValue, value, stack));
+    });
+  } else if (isMap(value)) {
+    value.forEach(function(subValue, key) {
+      result.set(key, baseClone(subValue, bitmask, customizer, key, value, stack));
+    });
+  }
+
+  var keysFunc = isFull
+    ? (isFlat ? getAllKeysIn : getAllKeys)
+    : (isFlat ? keysIn : keys);
+
+  var props = isArr ? undefined : keysFunc(value);
+  arrayEach(props || value, function(subValue, key) {
+    if (props) {
+      key = subValue;
+      subValue = value[key];
+    }
+    // Recursively populate clone (susceptible to call stack limits).
+    assignValue(result, key, baseClone(subValue, bitmask, customizer, key, value, stack));
   });
-  return isArr ? result : copySymbols(value, result);
+  return result;
 }
 
 export default baseClone;

_baseConforms.js

@@ -1,31 +1,17 @@
-import keys from './keys';
+import baseConformsTo from './_baseConformsTo.js';
+import keys from './keys.js';
 
 /**
  * The base implementation of `_.conforms` which doesn't clone `source`.
  *
  * @private
  * @param {Object} source The object of property predicates to conform to.
- * @returns {Function} Returns the new function.
+ * @returns {Function} Returns the new spec function.
  */
 function baseConforms(source) {
-  var props = keys(source),
+  var props = keys(source);
-      length = props.length;
-
   return function(object) {
-    if (object == null) {
+    return baseConformsTo(object, source, props);
-      return !length;
-    }
-    var index = length;
-    while (index--) {
-      var key = props[index],
-          predicate = source[key],
-          value = object[key];
-
-      if ((value === undefined && !(key in Object(object))) || !predicate(value)) {
-        return false;
-      }
-    }
-    return true;
   };
 }
 

_baseConformsTo.js

@@ -0,0 +1,27 @@
+/**
+ * The base implementation of `_.conformsTo` which accepts `props` to check.
+ *
+ * @private
+ * @param {Object} object The object to inspect.
+ * @param {Object} source The object of property predicates to conform to.
+ * @returns {boolean} Returns `true` if `object` conforms, else `false`.
+ */
+function baseConformsTo(object, source, props) {
+  var length = props.length;
+  if (object == null) {
+    return !length;
+  }
+  object = Object(object);
+  while (length--) {
+    var key = props[length],
+        predicate = source[key],
+        value = object[key];
+
+    if ((value === undefined && !(key in object)) || !predicate(value)) {
+      return false;
+    }
+  }
+  return true;
+}
+
+export default baseConformsTo;

_baseCreate.js

@@ -1,22 +1,29 @@
-import isObject from './isObject';
+import isObject from './isObject.js';
+
+/** Built-in value references. */
+var objectCreate = Object.create;
 
 /**
  * The base implementation of `_.create` without support for assigning
  * properties to the created object.
  *
  * @private
- * @param {Object} prototype The object to inherit from.
+ * @param {Object} proto The object to inherit from.
  * @returns {Object} Returns the new object.
  */
 var baseCreate = (function() {
   function object() {}
-  return function(prototype) {
+  return function(proto) {
-    if (isObject(prototype)) {
+    if (!isObject(proto)) {
-      object.prototype = prototype;
+      return {};
-      var result = new object;
-      object.prototype = undefined;
     }
-    return result || {};
+    if (objectCreate) {
+      return objectCreate(proto);
+    }
+    object.prototype = proto;
+    var result = new object;
+    object.prototype = undefined;
+    return result;
   };
 }());
 

_baseDelay.js

@@ -1,15 +1,15 @@
-/** Used as the `TypeError` message for "Functions" methods. */
+/** Error message constants. */
 var FUNC_ERROR_TEXT = 'Expected a function';
 
 /**
- * The base implementation of `_.delay` and `_.defer` which accepts an array
+ * The base implementation of `_.delay` and `_.defer` which accepts `args`
- * of `func` arguments.
+ * to provide to `func`.
  *
  * @private
  * @param {Function} func The function to delay.
  * @param {number} wait The number of milliseconds to delay invocation.
- * @param {Object} args The arguments provide to `func`.
+ * @param {Array} args The arguments to provide to `func`.
- * @returns {number} Returns the timer id.
+ * @returns {number|Object} Returns the timer id or timeout object.
  */
 function baseDelay(func, wait, args) {
   if (typeof func != 'function') {

_baseDifference.js

@@ -1,16 +1,16 @@
-import SetCache from './_SetCache';
+import SetCache from './_SetCache.js';
-import arrayIncludes from './_arrayIncludes';
+import arrayIncludes from './_arrayIncludes.js';
-import arrayIncludesWith from './_arrayIncludesWith';
+import arrayIncludesWith from './_arrayIncludesWith.js';
-import arrayMap from './_arrayMap';
+import arrayMap from './_arrayMap.js';
-import baseUnary from './_baseUnary';
+import baseUnary from './_baseUnary.js';
-import cacheHas from './_cacheHas';
+import cacheHas from './_cacheHas.js';
 
 /** Used as the size to enable large array optimizations. */
 var LARGE_ARRAY_SIZE = 200;
 
 /**
- * The base implementation of methods like `_.difference` without support for
+ * The base implementation of methods like `_.difference` without support
- * excluding multiple arrays or iteratee shorthands.
+ * for excluding multiple arrays or iteratee shorthands.
  *
  * @private
  * @param {Array} array The array to inspect.
@@ -45,8 +45,9 @@ function baseDifference(array, values, iteratee, comparator) {
   outer:
   while (++index < length) {
     var value = array[index],
-        computed = iteratee ? iteratee(value) : value;
+        computed = iteratee == null ? value : iteratee(value);
 
+    value = (comparator || value !== 0) ? value : 0;
     if (isCommon && computed === computed) {
       var valuesIndex = valuesLength;
       while (valuesIndex--) {

_baseEach.js

@@ -1,5 +1,5 @@
-import baseForOwn from './_baseForOwn';
+import baseForOwn from './_baseForOwn.js';
-import createBaseEach from './_createBaseEach';
+import createBaseEach from './_createBaseEach.js';
 
 /**
  * The base implementation of `_.forEach` without support for iteratee shorthands.

_baseEachRight.js

@@ -1,5 +1,5 @@
-import baseForOwnRight from './_baseForOwnRight';
+import baseForOwnRight from './_baseForOwnRight.js';
-import createBaseEach from './_createBaseEach';
+import createBaseEach from './_createBaseEach.js';
 
 /**
  * The base implementation of `_.forEachRight` without support for iteratee shorthands.

_baseEvery.js

@@ -1,4 +1,4 @@
-import baseEach from './_baseEach';
+import baseEach from './_baseEach.js';
 
 /**
  * The base implementation of `_.every` without support for iteratee shorthands.
@@ -6,7 +6,8 @@ import baseEach from './_baseEach';
  * @private
  * @param {Array|Object} collection The collection to iterate over.
  * @param {Function} predicate The function invoked per iteration.
- * @returns {boolean} Returns `true` if all elements pass the predicate check, else `false`
+ * @returns {boolean} Returns `true` if all elements pass the predicate check,
+ *  else `false`
  */
 function baseEvery(collection, predicate) {
   var result = true;

_baseExtremum.js

@@ -1,3 +1,5 @@
+import isSymbol from './isSymbol.js';
+
 /**
  * The base implementation of methods like `_.max` and `_.min` which accepts a
  * `comparator` to determine the extremum value.
@@ -17,7 +19,7 @@ function baseExtremum(array, iteratee, comparator) {
         current = iteratee(value);
 
     if (current != null && (computed === undefined
-          ? current === current
+          ? (current === current && !isSymbol(current))
           : comparator(current, computed)
         )) {
       var computed = current,

_baseFill.js

@@ -1,5 +1,5 @@
-import toInteger from './toInteger';
+import toInteger from './toInteger.js';
-import toLength from './toLength';
+import toLength from './toLength.js';
 
 /**
  * The base implementation of `_.fill` without an iteratee call guard.

_baseFilter.js

@@ -1,4 +1,4 @@
-import baseEach from './_baseEach';
+import baseEach from './_baseEach.js';
 
 /**
  * The base implementation of `_.filter` without support for iteratee shorthands.

_baseFind.js

@@ -1,24 +0,0 @@
-/**
- * The base implementation of methods like `_.find` and `_.findKey`, without
- * support for iteratee shorthands, which iterates over `collection` using
- * `eachFunc`.
- *
- * @private
- * @param {Array|Object} collection The collection to search.
- * @param {Function} predicate The function invoked per iteration.
- * @param {Function} eachFunc The function to iterate over `collection`.
- * @param {boolean} [retKey] Specify returning the key of the found element instead of the element itself.
- * @returns {*} Returns the found element or its key, else `undefined`.
- */
-function baseFind(collection, predicate, eachFunc, retKey) {
-  var result;
-  eachFunc(collection, function(value, key, collection) {
-    if (predicate(value, key, collection)) {
-      result = retKey ? key : value;
-      return false;
-    }
-  });
-  return result;
-}
-
-export default baseFind;

_baseFindIndex.js

@@ -3,14 +3,15 @@
  * support for iteratee shorthands.
  *
  * @private
- * @param {Array} array The array to search.
+ * @param {Array} array The array to inspect.
  * @param {Function} predicate The function invoked per iteration.
+ * @param {number} fromIndex The index to search from.
  * @param {boolean} [fromRight] Specify iterating from right to left.
  * @returns {number} Returns the index of the matched value, else `-1`.
  */
-function baseFindIndex(array, predicate, fromRight) {
+function baseFindIndex(array, predicate, fromIndex, fromRight) {
   var length = array.length,
-      index = fromRight ? length : -1;
+      index = fromIndex + (fromRight ? 1 : -1);
 
   while ((fromRight ? index-- : ++index < length)) {
     if (predicate(array[index], index, array)) {

_baseFindKey.js

@@ -0,0 +1,23 @@
+/**
+ * The base implementation of methods like `_.findKey` and `_.findLastKey`,
+ * without support for iteratee shorthands, which iterates over `collection`
+ * using `eachFunc`.
+ *
+ * @private
+ * @param {Array|Object} collection The collection to inspect.
+ * @param {Function} predicate The function invoked per iteration.
+ * @param {Function} eachFunc The function to iterate over `collection`.
+ * @returns {*} Returns the found element or its key, else `undefined`.
+ */
+function baseFindKey(collection, predicate, eachFunc) {
+  var result;
+  eachFunc(collection, function(value, key, collection) {
+    if (predicate(value, key, collection)) {
+      result = key;
+      return false;
+    }
+  });
+  return result;
+}
+
+export default baseFindKey;

_baseFlatten.js

@@ -1,31 +1,30 @@
-import arrayPush from './_arrayPush';
+import arrayPush from './_arrayPush.js';
-import isArguments from './isArguments';
+import isFlattenable from './_isFlattenable.js';
-import isArray from './isArray';
-import isArrayLikeObject from './isArrayLikeObject';
 
 /**
  * The base implementation of `_.flatten` with support for restricting flattening.
  *
  * @private
  * @param {Array} array The array to flatten.
- * @param {boolean} [isDeep] Specify a deep flatten.
+ * @param {number} depth The maximum recursion depth.
- * @param {boolean} [isStrict] Restrict flattening to arrays-like objects.
+ * @param {boolean} [predicate=isFlattenable] The function invoked per iteration.
+ * @param {boolean} [isStrict] Restrict to values that pass `predicate` checks.
  * @param {Array} [result=[]] The initial result value.
  * @returns {Array} Returns the new flattened array.
  */
-function baseFlatten(array, isDeep, isStrict, result) {
+function baseFlatten(array, depth, predicate, isStrict, result) {
-  result || (result = []);
-
   var index = -1,
       length = array.length;
 
+  predicate || (predicate = isFlattenable);
+  result || (result = []);
+
   while (++index < length) {
     var value = array[index];
-    if (isArrayLikeObject(value) &&
+    if (depth > 0 && predicate(value)) {
-        (isStrict || isArray(value) || isArguments(value))) {
+      if (depth > 1) {
-      if (isDeep) {
         // Recursively flatten arrays (susceptible to call stack limits).
-        baseFlatten(value, isDeep, isStrict, result);
+        baseFlatten(value, depth - 1, predicate, isStrict, result);
       } else {
         arrayPush(result, value);
       }

_baseFor.js

@@ -1,10 +1,9 @@
-import createBaseFor from './_createBaseFor';
+import createBaseFor from './_createBaseFor.js';
 
 /**
- * The base implementation of `baseForIn` and `baseForOwn` which iterates
+ * The base implementation of `baseForOwn` which iterates over `object`
- * over `object` properties returned by `keysFunc` invoking `iteratee` for
+ * properties returned by `keysFunc` and invokes `iteratee` for each property.
- * each property. Iteratee functions may exit iteration early by explicitly
+ * Iteratee functions may exit iteration early by explicitly returning `false`.
- * returning `false`.
  *
  * @private
  * @param {Object} object The object to iterate over.

_baseForIn.js

@@ -1,16 +0,0 @@
-import baseFor from './_baseFor';
-import keysIn from './keysIn';
-
-/**
- * The base implementation of `_.forIn` without support for iteratee shorthands.
- *
- * @private
- * @param {Object} object The object to iterate over.
- * @param {Function} iteratee The function invoked per iteration.
- * @returns {Object} Returns `object`.
- */
-function baseForIn(object, iteratee) {
-  return object == null ? object : baseFor(object, iteratee, keysIn);
-}
-
-export default baseForIn;

_baseForOwn.js

@@ -1,5 +1,5 @@
-import baseFor from './_baseFor';
+import baseFor from './_baseFor.js';
-import keys from './keys';
+import keys from './keys.js';
 
 /**
  * The base implementation of `_.forOwn` without support for iteratee shorthands.

_baseForOwnRight.js

@@ -1,5 +1,5 @@
-import baseForRight from './_baseForRight';
+import baseForRight from './_baseForRight.js';
-import keys from './keys';
+import keys from './keys.js';
 
 /**
  * The base implementation of `_.forOwnRight` without support for iteratee shorthands.

_baseForRight.js

@@ -1,4 +1,4 @@
-import createBaseFor from './_createBaseFor';
+import createBaseFor from './_createBaseFor.js';
 
 /**
  * This function is like `baseFor` except that it iterates over properties

_baseFunctions.js

@@ -1,14 +1,14 @@
-import arrayFilter from './_arrayFilter';
+import arrayFilter from './_arrayFilter.js';
-import isFunction from './isFunction';
+import isFunction from './isFunction.js';
 
 /**
  * The base implementation of `_.functions` which creates an array of
- * `object` function property names filtered from those provided.
+ * `object` function property names filtered from `props`.
  *
  * @private
  * @param {Object} object The object to inspect.
  * @param {Array} props The property names to filter.
- * @returns {Array} Returns the new array of filtered property names.
+ * @returns {Array} Returns the function names.
  */
 function baseFunctions(object, props) {
   return arrayFilter(props, function(key) {

_baseGet.js

@@ -1,5 +1,5 @@
-import baseToPath from './_baseToPath';
+import castPath from './_castPath.js';
-import isKey from './_isKey';
+import toKey from './_toKey.js';
 
 /**
  * The base implementation of `_.get` without support for default values.
@@ -10,13 +10,13 @@ import isKey from './_isKey';
  * @returns {*} Returns the resolved value.
  */
 function baseGet(object, path) {
-  path = isKey(path, object) ? [path + ''] : baseToPath(path);
+  path = castPath(path, object);
 
   var index = 0,
       length = path.length;
 
   while (object != null && index < length) {
-    object = object[path[index++]];
+    object = object[toKey(path[index++])];
   }
   return (index && index == length) ? object : undefined;
 }

_baseGetAllKeys.js

@@ -0,0 +1,20 @@
+import arrayPush from './_arrayPush.js';
+import isArray from './isArray.js';
+
+/**
+ * The base implementation of `getAllKeys` and `getAllKeysIn` which uses
+ * `keysFunc` and `symbolsFunc` to get the enumerable property names and
+ * symbols of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @param {Function} keysFunc The function to get the keys of `object`.
+ * @param {Function} symbolsFunc The function to get the symbols of `object`.
+ * @returns {Array} Returns the array of property names and symbols.
+ */
+function baseGetAllKeys(object, keysFunc, symbolsFunc) {
+  var result = keysFunc(object);
+  return isArray(object) ? result : arrayPush(result, symbolsFunc(object));
+}
+
+export default baseGetAllKeys;

_baseGetTag.js

@@ -0,0 +1,28 @@
+import Symbol from './_Symbol.js';
+import getRawTag from './_getRawTag.js';
+import objectToString from './_objectToString.js';
+
+/** `Object#toString` result references. */
+var nullTag = '[object Null]',
+    undefinedTag = '[object Undefined]';
+
+/** Built-in value references. */
+var symToStringTag = Symbol ? Symbol.toStringTag : undefined;
+
+/**
+ * The base implementation of `getTag` without fallbacks for buggy environments.
+ *
+ * @private
+ * @param {*} value The value to query.
+ * @returns {string} Returns the `toStringTag`.
+ */
+function baseGetTag(value) {
+  if (value == null) {
+    return value === undefined ? undefinedTag : nullTag;
+  }
+  return (symToStringTag && symToStringTag in Object(value))
+    ? getRawTag(value)
+    : objectToString(value);
+}
+
+export default baseGetTag;

_baseGt.js

@@ -0,0 +1,14 @@
+/**
+ * The base implementation of `_.gt` which doesn't coerce arguments.
+ *
+ * @private
+ * @param {*} value The value to compare.
+ * @param {*} other The other value to compare.
+ * @returns {boolean} Returns `true` if `value` is greater than `other`,
+ *  else `false`.
+ */
+function baseGt(value, other) {
+  return value > other;
+}
+
+export default baseGt;

_baseHas.js

@@ -4,23 +4,16 @@ var objectProto = Object.prototype;
 /** Used to check objects for own properties. */
 var hasOwnProperty = objectProto.hasOwnProperty;
 
-/** Built-in value references. */
-var getPrototypeOf = Object.getPrototypeOf;
-
 /**
  * The base implementation of `_.has` without support for deep paths.
  *
  * @private
- * @param {Object} object The object to query.
+ * @param {Object} [object] The object to query.
  * @param {Array|string} key The key to check.
  * @returns {boolean} Returns `true` if `key` exists, else `false`.
  */
 function baseHas(object, key) {
-  // Avoid a bug in IE 10-11 where objects with a [[Prototype]] of `null`,
+  return object != null && hasOwnProperty.call(object, key);
-  // that are composed entirely of index properties, return `false` for
-  // `hasOwnProperty` checks of them.
-  return hasOwnProperty.call(object, key) ||
-    (typeof object == 'object' && key in object && getPrototypeOf(object) === null);
 }
 
 export default baseHas;

_baseHasIn.js

@@ -2,12 +2,12 @@
  * The base implementation of `_.hasIn` without support for deep paths.
  *
  * @private
- * @param {Object} object The object to query.
+ * @param {Object} [object] The object to query.
  * @param {Array|string} key The key to check.
  * @returns {boolean} Returns `true` if `key` exists, else `false`.
  */
 function baseHasIn(object, key) {
-  return key in Object(object);
+  return object != null && key in Object(object);
 }
 
 export default baseHasIn;

_baseInRange.js

@@ -3,7 +3,7 @@ var nativeMax = Math.max,
     nativeMin = Math.min;
 
 /**
- * The base implementation of `_.inRange` which doesn't coerce arguments to numbers.
+ * The base implementation of `_.inRange` which doesn't coerce arguments.
  *
  * @private
  * @param {number} number The number to check.

_baseIndexOf.js

@@ -1,27 +1,20 @@
-import indexOfNaN from './_indexOfNaN';
+import baseFindIndex from './_baseFindIndex.js';
+import baseIsNaN from './_baseIsNaN.js';
+import strictIndexOf from './_strictIndexOf.js';
 
 /**
  * The base implementation of `_.indexOf` without `fromIndex` bounds checks.
  *
  * @private
- * @param {Array} array The array to search.
+ * @param {Array} array The array to inspect.
  * @param {*} value The value to search for.
  * @param {number} fromIndex The index to search from.
  * @returns {number} Returns the index of the matched value, else `-1`.
  */
 function baseIndexOf(array, value, fromIndex) {
-  if (value !== value) {
+  return value === value
-    return indexOfNaN(array, fromIndex);
+    ? strictIndexOf(array, value, fromIndex)
-  }
+    : baseFindIndex(array, baseIsNaN, fromIndex);
-  var index = fromIndex - 1,
-      length = array.length;
-
-  while (++index < length) {
-    if (array[index] === value) {
-      return index;
-    }
-  }
-  return -1;
 }
 
 export default baseIndexOf;

_baseIndexOfWith.js

@@ -0,0 +1,23 @@
+/**
+ * This function is like `baseIndexOf` except that it accepts a comparator.
+ *
+ * @private
+ * @param {Array} array The array to inspect.
+ * @param {*} value The value to search for.
+ * @param {number} fromIndex The index to search from.
+ * @param {Function} comparator The comparator invoked per element.
+ * @returns {number} Returns the index of the matched value, else `-1`.
+ */
+function baseIndexOfWith(array, value, fromIndex, comparator) {
+  var index = fromIndex - 1,
+      length = array.length;
+
+  while (++index < length) {
+    if (comparator(array[index], value)) {
+      return index;
+    }
+  }
+  return -1;
+}
+
+export default baseIndexOfWith;

_baseIntersection.js

@@ -1,9 +1,12 @@
-import SetCache from './_SetCache';
+import SetCache from './_SetCache.js';
-import arrayIncludes from './_arrayIncludes';
+import arrayIncludes from './_arrayIncludes.js';
-import arrayIncludesWith from './_arrayIncludesWith';
+import arrayIncludesWith from './_arrayIncludesWith.js';
-import arrayMap from './_arrayMap';
+import arrayMap from './_arrayMap.js';
-import baseUnary from './_baseUnary';
+import baseUnary from './_baseUnary.js';
-import cacheHas from './_cacheHas';
+import cacheHas from './_cacheHas.js';
+
+/* Built-in method references for those with the same name as other `lodash` methods. */
+var nativeMin = Math.min;
 
 /**
  * The base implementation of methods like `_.intersection`, without support
@@ -17,9 +20,11 @@ import cacheHas from './_cacheHas';
  */
 function baseIntersection(arrays, iteratee, comparator) {
   var includes = comparator ? arrayIncludesWith : arrayIncludes,
+      length = arrays[0].length,
       othLength = arrays.length,
       othIndex = othLength,
       caches = Array(othLength),
+      maxLength = Infinity,
       result = [];
 
   while (othIndex--) {
@@ -27,26 +32,33 @@ function baseIntersection(arrays, iteratee, comparator) {
     if (othIndex && iteratee) {
       array = arrayMap(array, baseUnary(iteratee));
     }
-    caches[othIndex] = !comparator && (iteratee || array.length >= 120)
+    maxLength = nativeMin(array.length, maxLength);
+    caches[othIndex] = !comparator && (iteratee || (length >= 120 && array.length >= 120))
       ? new SetCache(othIndex && array)
       : undefined;
   }
   array = arrays[0];
 
   var index = -1,
-      length = array.length,
       seen = caches[0];
 
   outer:
-  while (++index < length) {
+  while (++index < length && result.length < maxLength) {
     var value = array[index],
         computed = iteratee ? iteratee(value) : value;
 
-    if (!(seen ? cacheHas(seen, computed) : includes(result, computed, comparator))) {
+    value = (comparator || value !== 0) ? value : 0;
-      var othIndex = othLength;
+    if (!(seen
+          ? cacheHas(seen, computed)
+          : includes(result, computed, comparator)
+        )) {
+      othIndex = othLength;
       while (--othIndex) {
         var cache = caches[othIndex];
-        if (!(cache ? cacheHas(cache, computed) : includes(arrays[othIndex], computed, comparator))) {
+        if (!(cache
+              ? cacheHas(cache, computed)
+              : includes(arrays[othIndex], computed, comparator))
+            ) {
           continue outer;
         }
       }

_baseInverter.js

@@ -1,4 +1,4 @@
-import baseForOwn from './_baseForOwn';
+import baseForOwn from './_baseForOwn.js';
 
 /**
  * The base implementation of `_.invert` and `_.invertBy` which inverts

_baseInvoke.js

@@ -1,8 +1,8 @@
-import apply from './_apply';
+import apply from './_apply.js';
-import baseToPath from './_baseToPath';
+import castPath from './_castPath.js';
-import isKey from './_isKey';
+import last from './last.js';
-import last from './last';
+import parent from './_parent.js';
-import parent from './_parent';
+import toKey from './_toKey.js';
 
 /**
  * The base implementation of `_.invoke` without support for individual
@@ -15,12 +15,9 @@ import parent from './_parent';
  * @returns {*} Returns the result of the invoked method.
  */
 function baseInvoke(object, path, args) {
-  if (!isKey(path, object)) {
+  path = castPath(path, object);
-    path = baseToPath(path);
+  object = parent(object, path);
-    object = parent(object, path);
+  var func = object == null ? object : object[toKey(last(path))];
-    path = last(path);
-  }
-  var func = object == null ? object : object[path];
   return func == null ? undefined : apply(func, object, args);
 }
 

_baseIsArguments.js

@@ -0,0 +1,18 @@
+import baseGetTag from './_baseGetTag.js';
+import isObjectLike from './isObjectLike.js';
+
+/** `Object#toString` result references. */
+var argsTag = '[object Arguments]';
+
+/**
+ * The base implementation of `_.isArguments`.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is an `arguments` object,
+ */
+function baseIsArguments(value) {
+  return isObjectLike(value) && baseGetTag(value) == argsTag;
+}
+
+export default baseIsArguments;

_baseIsArrayBuffer.js

@@ -0,0 +1,17 @@
+import baseGetTag from './_baseGetTag.js';
+import isObjectLike from './isObjectLike.js';
+
+var arrayBufferTag = '[object ArrayBuffer]';
+
+/**
+ * The base implementation of `_.isArrayBuffer` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is an array buffer, else `false`.
+ */
+function baseIsArrayBuffer(value) {
+  return isObjectLike(value) && baseGetTag(value) == arrayBufferTag;
+}
+
+export default baseIsArrayBuffer;

_baseIsDate.js

@@ -0,0 +1,18 @@
+import baseGetTag from './_baseGetTag.js';
+import isObjectLike from './isObjectLike.js';
+
+/** `Object#toString` result references. */
+var dateTag = '[object Date]';
+
+/**
+ * The base implementation of `_.isDate` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a date object, else `false`.
+ */
+function baseIsDate(value) {
+  return isObjectLike(value) && baseGetTag(value) == dateTag;
+}
+
+export default baseIsDate;

_baseIsEqual.js

@@ -1,6 +1,5 @@
-import baseIsEqualDeep from './_baseIsEqualDeep';
+import baseIsEqualDeep from './_baseIsEqualDeep.js';
-import isObject from './isObject';
+import isObjectLike from './isObjectLike.js';
-import isObjectLike from './isObjectLike';
 
 /**
  * The base implementation of `_.isEqual` which supports partial comparisons
@@ -9,22 +8,21 @@ import isObjectLike from './isObjectLike';
  * @private
  * @param {*} value The value to compare.
  * @param {*} other The other value to compare.
+ * @param {boolean} bitmask The bitmask flags.
+ *  1 - Unordered comparison
+ *  2 - Partial comparison
  * @param {Function} [customizer] The function to customize comparisons.
- * @param {boolean} [bitmask] The bitmask of comparison flags.
- *  The bitmask may be composed of the following flags:
- *     1 - Unordered comparison
- *     2 - Partial comparison
  * @param {Object} [stack] Tracks traversed `value` and `other` objects.
  * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
  */
-function baseIsEqual(value, other, customizer, bitmask, stack) {
+function baseIsEqual(value, other, bitmask, customizer, stack) {
   if (value === other) {
     return true;
   }
-  if (value == null || other == null || (!isObject(value) && !isObjectLike(other))) {
+  if (value == null || other == null || (!isObjectLike(value) && !isObjectLike(other))) {
     return value !== value && other !== other;
   }
-  return baseIsEqualDeep(value, other, baseIsEqual, customizer, bitmask, stack);
+  return baseIsEqualDeep(value, other, bitmask, customizer, baseIsEqual, stack);
 }
 
 export default baseIsEqual;

_baseIsEqualDeep.js

@@ -1,14 +1,14 @@
-import Stack from './_Stack';
+import Stack from './_Stack.js';
-import equalArrays from './_equalArrays';
+import equalArrays from './_equalArrays.js';
-import equalByTag from './_equalByTag';
+import equalByTag from './_equalByTag.js';
-import equalObjects from './_equalObjects';
+import equalObjects from './_equalObjects.js';
-import getTag from './_getTag';
+import getTag from './_getTag.js';
-import isArray from './isArray';
+import isArray from './isArray.js';
-import isHostObject from './_isHostObject';
+import isBuffer from './isBuffer.js';
-import isTypedArray from './isTypedArray';
+import isTypedArray from './isTypedArray.js';
 
-/** Used to compose bitmasks for comparison styles. */
+/** Used to compose bitmasks for value comparisons. */
-var PARTIAL_COMPARE_FLAG = 2;
+var COMPARE_PARTIAL_FLAG = 1;
 
 /** `Object#toString` result references. */
 var argsTag = '[object Arguments]',
@@ -29,55 +29,55 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * @private
  * @param {Object} object The object to compare.
  * @param {Object} other The other object to compare.
+ * @param {number} bitmask The bitmask flags. See `baseIsEqual` for more details.
+ * @param {Function} customizer The function to customize comparisons.
  * @param {Function} equalFunc The function to determine equivalents of values.
- * @param {Function} [customizer] The function to customize comparisons.
- * @param {number} [bitmask] The bitmask of comparison flags. See `baseIsEqual` for more details.
  * @param {Object} [stack] Tracks traversed `object` and `other` objects.
  * @returns {boolean} Returns `true` if the objects are equivalent, else `false`.
  */
-function baseIsEqualDeep(object, other, equalFunc, customizer, bitmask, stack) {
+function baseIsEqualDeep(object, other, bitmask, customizer, equalFunc, stack) {
   var objIsArr = isArray(object),
       othIsArr = isArray(other),
-      objTag = arrayTag,
+      objTag = objIsArr ? arrayTag : getTag(object),
-      othTag = arrayTag;
+      othTag = othIsArr ? arrayTag : getTag(other);
 
-  if (!objIsArr) {
+  objTag = objTag == argsTag ? objectTag : objTag;
-    objTag = getTag(object);
+  othTag = othTag == argsTag ? objectTag : othTag;
-    if (objTag == argsTag) {
+
-      objTag = objectTag;
+  var objIsObj = objTag == objectTag,
-    } else if (objTag != objectTag) {
+      othIsObj = othTag == objectTag,
-      objIsArr = isTypedArray(object);
-    }
-  }
-  if (!othIsArr) {
-    othTag = getTag(other);
-    if (othTag == argsTag) {
-      othTag = objectTag;
-    } else if (othTag != objectTag) {
-      othIsArr = isTypedArray(other);
-    }
-  }
-  var objIsObj = objTag == objectTag && !isHostObject(object),
-      othIsObj = othTag == objectTag && !isHostObject(other),
       isSameTag = objTag == othTag;
 
-  if (isSameTag && !(objIsArr || objIsObj)) {
+  if (isSameTag && isBuffer(object)) {
-    return equalByTag(object, other, objTag, equalFunc, customizer, bitmask);
+    if (!isBuffer(other)) {
+      return false;
+    }
+    objIsArr = true;
+    objIsObj = false;
   }
-  var isPartial = bitmask & PARTIAL_COMPARE_FLAG;
+  if (isSameTag && !objIsObj) {
-  if (!isPartial) {
+    stack || (stack = new Stack);
+    return (objIsArr || isTypedArray(object))
+      ? equalArrays(object, other, bitmask, customizer, equalFunc, stack)
+      : equalByTag(object, other, objTag, bitmask, customizer, equalFunc, stack);
+  }
+  if (!(bitmask & COMPARE_PARTIAL_FLAG)) {
     var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
         othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');
 
     if (objIsWrapped || othIsWrapped) {
-      return equalFunc(objIsWrapped ? object.value() : object, othIsWrapped ? other.value() : other, customizer, bitmask, stack);
+      var objUnwrapped = objIsWrapped ? object.value() : object,
+          othUnwrapped = othIsWrapped ? other.value() : other;
+
+      stack || (stack = new Stack);
+      return equalFunc(objUnwrapped, othUnwrapped, bitmask, customizer, stack);
     }
   }
   if (!isSameTag) {
     return false;
   }
   stack || (stack = new Stack);
-  return (objIsArr ? equalArrays : equalObjects)(object, other, equalFunc, customizer, bitmask, stack);
+  return equalObjects(object, other, bitmask, customizer, equalFunc, stack);
 }
 
 export default baseIsEqualDeep;

_baseIsMap.js

@@ -0,0 +1,18 @@
+import getTag from './_getTag.js';
+import isObjectLike from './isObjectLike.js';
+
+/** `Object#toString` result references. */
+var mapTag = '[object Map]';
+
+/**
+ * The base implementation of `_.isMap` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a map, else `false`.
+ */
+function baseIsMap(value) {
+  return isObjectLike(value) && getTag(value) == mapTag;
+}
+
+export default baseIsMap;

_baseIsMatch.js

@@ -1,9 +1,9 @@
-import Stack from './_Stack';
+import Stack from './_Stack.js';
-import baseIsEqual from './_baseIsEqual';
+import baseIsEqual from './_baseIsEqual.js';
 
-/** Used to compose bitmasks for comparison styles. */
+/** Used to compose bitmasks for value comparisons. */
-var UNORDERED_COMPARE_FLAG = 1,
+var COMPARE_PARTIAL_FLAG = 1,
-    PARTIAL_COMPARE_FLAG = 2;
+    COMPARE_UNORDERED_FLAG = 2;
 
 /**
  * The base implementation of `_.isMatch` without support for iteratee shorthands.
@@ -44,11 +44,12 @@ function baseIsMatch(object, source, matchData, customizer) {
         return false;
       }
     } else {
-      var stack = new Stack,
+      var stack = new Stack;
-          result = customizer ? customizer(objValue, srcValue, key, object, source, stack) : undefined;
+      if (customizer) {
-
+        var result = customizer(objValue, srcValue, key, object, source, stack);
+      }
       if (!(result === undefined
-            ? baseIsEqual(srcValue, objValue, customizer, UNORDERED_COMPARE_FLAG | PARTIAL_COMPARE_FLAG, stack)
+            ? baseIsEqual(srcValue, objValue, COMPARE_PARTIAL_FLAG | COMPARE_UNORDERED_FLAG, customizer, stack)
             : result
           )) {
         return false;

_baseIsNaN.js

@@ -0,0 +1,12 @@
+/**
+ * The base implementation of `_.isNaN` without support for number objects.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is `NaN`, else `false`.
+ */
+function baseIsNaN(value) {
+  return value !== value;
+}
+
+export default baseIsNaN;

_baseIsNative.js

@@ -0,0 +1,47 @@
+import isFunction from './isFunction.js';
+import isMasked from './_isMasked.js';
+import isObject from './isObject.js';
+import toSource from './_toSource.js';
+
+/**
+ * Used to match `RegExp`
+ * [syntax characters](http://ecma-international.org/ecma-262/7.0/#sec-patterns).
+ */
+var reRegExpChar = /[\\^$.*+?()[\]{}|]/g;
+
+/** Used to detect host constructors (Safari). */
+var reIsHostCtor = /^\[object .+?Constructor\]$/;
+
+/** Used for built-in method references. */
+var funcProto = Function.prototype,
+    objectProto = Object.prototype;
+
+/** Used to resolve the decompiled source of functions. */
+var funcToString = funcProto.toString;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
+
+/** Used to detect if a method is native. */
+var reIsNative = RegExp('^' +
+  funcToString.call(hasOwnProperty).replace(reRegExpChar, '\\$&')
+  .replace(/hasOwnProperty|(function).*?(?=\\\()| for .+?(?=\\\])/g, '$1.*?') + '$'
+);
+
+/**
+ * The base implementation of `_.isNative` without bad shim checks.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a native function,
+ *  else `false`.
+ */
+function baseIsNative(value) {
+  if (!isObject(value) || isMasked(value)) {
+    return false;
+  }
+  var pattern = isFunction(value) ? reIsNative : reIsHostCtor;
+  return pattern.test(toSource(value));
+}
+
+export default baseIsNative;

_baseIsRegExp.js

@@ -0,0 +1,18 @@
+import baseGetTag from './_baseGetTag.js';
+import isObjectLike from './isObjectLike.js';
+
+/** `Object#toString` result references. */
+var regexpTag = '[object RegExp]';
+
+/**
+ * The base implementation of `_.isRegExp` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a regexp, else `false`.
+ */
+function baseIsRegExp(value) {
+  return isObjectLike(value) && baseGetTag(value) == regexpTag;
+}
+
+export default baseIsRegExp;

_baseIsSet.js

@@ -0,0 +1,18 @@
+import getTag from './_getTag.js';
+import isObjectLike from './isObjectLike.js';
+
+/** `Object#toString` result references. */
+var setTag = '[object Set]';
+
+/**
+ * The base implementation of `_.isSet` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a set, else `false`.
+ */
+function baseIsSet(value) {
+  return isObjectLike(value) && getTag(value) == setTag;
+}
+
+export default baseIsSet;

_baseIsTypedArray.js

@@ -0,0 +1,60 @@
+import baseGetTag from './_baseGetTag.js';
+import isLength from './isLength.js';
+import isObjectLike from './isObjectLike.js';
+
+/** `Object#toString` result references. */
+var argsTag = '[object Arguments]',
+    arrayTag = '[object Array]',
+    boolTag = '[object Boolean]',
+    dateTag = '[object Date]',
+    errorTag = '[object Error]',
+    funcTag = '[object Function]',
+    mapTag = '[object Map]',
+    numberTag = '[object Number]',
+    objectTag = '[object Object]',
+    regexpTag = '[object RegExp]',
+    setTag = '[object Set]',
+    stringTag = '[object String]',
+    weakMapTag = '[object WeakMap]';
+
+var arrayBufferTag = '[object ArrayBuffer]',
+    dataViewTag = '[object DataView]',
+    float32Tag = '[object Float32Array]',
+    float64Tag = '[object Float64Array]',
+    int8Tag = '[object Int8Array]',
+    int16Tag = '[object Int16Array]',
+    int32Tag = '[object Int32Array]',
+    uint8Tag = '[object Uint8Array]',
+    uint8ClampedTag = '[object Uint8ClampedArray]',
+    uint16Tag = '[object Uint16Array]',
+    uint32Tag = '[object Uint32Array]';
+
+/** Used to identify `toStringTag` values of typed arrays. */
+var typedArrayTags = {};
+typedArrayTags[float32Tag] = typedArrayTags[float64Tag] =
+typedArrayTags[int8Tag] = typedArrayTags[int16Tag] =
+typedArrayTags[int32Tag] = typedArrayTags[uint8Tag] =
+typedArrayTags[uint8ClampedTag] = typedArrayTags[uint16Tag] =
+typedArrayTags[uint32Tag] = true;
+typedArrayTags[argsTag] = typedArrayTags[arrayTag] =
+typedArrayTags[arrayBufferTag] = typedArrayTags[boolTag] =
+typedArrayTags[dataViewTag] = typedArrayTags[dateTag] =
+typedArrayTags[errorTag] = typedArrayTags[funcTag] =
+typedArrayTags[mapTag] = typedArrayTags[numberTag] =
+typedArrayTags[objectTag] = typedArrayTags[regexpTag] =
+typedArrayTags[setTag] = typedArrayTags[stringTag] =
+typedArrayTags[weakMapTag] = false;
+
+/**
+ * The base implementation of `_.isTypedArray` without Node.js optimizations.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is a typed array, else `false`.
+ */
+function baseIsTypedArray(value) {
+  return isObjectLike(value) &&
+    isLength(value.length) && !!typedArrayTags[baseGetTag(value)];
+}
+
+export default baseIsTypedArray;

_baseIteratee.js

@@ -1,8 +1,8 @@
-import baseMatches from './_baseMatches';
+import baseMatches from './_baseMatches.js';
-import baseMatchesProperty from './_baseMatchesProperty';
+import baseMatchesProperty from './_baseMatchesProperty.js';
-import identity from './identity';
+import identity from './identity.js';
-import isArray from './isArray';
+import isArray from './isArray.js';
-import property from './property';
+import property from './property.js';
 
 /**
  * The base implementation of `_.iteratee`.
@@ -12,14 +12,15 @@ import property from './property';
  * @returns {Function} Returns the iteratee.
  */
 function baseIteratee(value) {
-  var type = typeof value;
+  // Don't store the `typeof` result in a variable to avoid a JIT bug in Safari 9.
-  if (type == 'function') {
+  // See https://bugs.webkit.org/show_bug.cgi?id=156034 for more details.
+  if (typeof value == 'function') {
     return value;
   }
   if (value == null) {
     return identity;
   }
-  if (type == 'object') {
+  if (typeof value == 'object') {
     return isArray(value)
       ? baseMatchesProperty(value[0], value[1])
       : baseMatches(value);

_baseKeys.js

@@ -1,17 +1,30 @@
-/* Built-in method references for those with the same name as other `lodash` methods. */
+import isPrototype from './_isPrototype.js';
-var nativeKeys = Object.keys;
+import nativeKeys from './_nativeKeys.js';
+
+/** Used for built-in method references. */
+var objectProto = Object.prototype;
+
+/** Used to check objects for own properties. */
+var hasOwnProperty = objectProto.hasOwnProperty;
 
 /**
- * The base implementation of `_.keys` which doesn't skip the constructor
+ * The base implementation of `_.keys` which doesn't treat sparse arrays as dense.
- * property of prototypes or treat sparse arrays as dense.
  *
  * @private
- * @type Function
  * @param {Object} object The object to query.
  * @returns {Array} Returns the array of property names.
  */
 function baseKeys(object) {
-  return nativeKeys(Object(object));
+  if (!isPrototype(object)) {
+    return nativeKeys(object);
+  }
+  var result = [];
+  for (var key in Object(object)) {
+    if (hasOwnProperty.call(object, key) && key != 'constructor') {
+      result.push(key);
+    }
+  }
+  return result;
 }
 
 export default baseKeys;

_baseKeysIn.js

@@ -1,36 +1,33 @@
-import Reflect from './_Reflect';
+import isObject from './isObject.js';
-import iteratorToArray from './_iteratorToArray';
+import isPrototype from './_isPrototype.js';
+import nativeKeysIn from './_nativeKeysIn.js';
 
 /** Used for built-in method references. */
 var objectProto = Object.prototype;
 
-/** Built-in value references. */
+/** Used to check objects for own properties. */
-var enumerate = Reflect ? Reflect.enumerate : undefined,
+var hasOwnProperty = objectProto.hasOwnProperty;
-    propertyIsEnumerable = objectProto.propertyIsEnumerable;
 
 /**
- * The base implementation of `_.keysIn` which doesn't skip the constructor
+ * The base implementation of `_.keysIn` which doesn't treat sparse arrays as dense.
- * property of prototypes or treat sparse arrays as dense.
  *
  * @private
  * @param {Object} object The object to query.
  * @returns {Array} Returns the array of property names.
  */
 function baseKeysIn(object) {
-  object = object == null ? object : Object(object);
+  if (!isObject(object)) {
+    return nativeKeysIn(object);
+  }
+  var isProto = isPrototype(object),
+      result = [];
 
-  var result = [];
   for (var key in object) {
-    result.push(key);
+    if (!(key == 'constructor' && (isProto || !hasOwnProperty.call(object, key)))) {
+      result.push(key);
+    }
   }
   return result;
 }
 
-// Fallback for IE < 9 with es6-shim.
-if (enumerate && !propertyIsEnumerable.call({ 'valueOf': 1 }, 'valueOf')) {
-  baseKeysIn = function(object) {
-    return iteratorToArray(enumerate(object));
-  };
-}
-
 export default baseKeysIn;