Bump to v3.9.3.

README.md

@@ -1,4 +1,4 @@
-# lodash v3.7.0
+# lodash v3.9.3
 
 The [modern build](https://github.com/lodash/lodash/wiki/Build-Differences) of [lodash](https://lodash.com/) exported as [Node.js](http://nodejs.org/)/[io.js](https://iojs.org/) modules.
 
@@ -28,7 +28,7 @@ var array = require('lodash/array');
 var chunk = require('lodash/array/chunk');
 ```
 
-See the [package source](https://github.com/lodash/lodash/tree/3.7.0-npm) for more details.
+See the [package source](https://github.com/lodash/lodash/tree/3.9.3-npm) for more details.
 
 **Note:**<br>
 Don’t assign values to the [special variable](http://nodejs.org/api/repl.html#repl_repl_features) `_` when in the REPL.<br>
@@ -39,15 +39,14 @@ Install [n_](https://www.npmjs.com/package/n_) for a REPL that includes lodash b
 lodash is also available in a variety of other builds & module formats.
 
  * npm packages for [modern](https://www.npmjs.com/package/lodash), [compatibility](https://www.npmjs.com/package/lodash-compat), & [per method](https://www.npmjs.com/browse/keyword/lodash-modularized) builds
- * AMD modules for [modern](https://github.com/lodash/lodash/tree/3.7.0-amd) & [compatibility](https://github.com/lodash/lodash-compat/tree/3.7.0-amd) builds
- * ES modules for the [modern](https://github.com/lodash/lodash/tree/3.7.0-es) build
+ * AMD modules for [modern](https://github.com/lodash/lodash/tree/3.9.3-amd) & [compatibility](https://github.com/lodash/lodash-compat/tree/3.9.3-amd) builds
+ * ES modules for the [modern](https://github.com/lodash/lodash/tree/3.9.3-es) build
 
 ## Further Reading
 
   * [API Documentation](https://lodash.com/docs)
   * [Build Differences](https://github.com/lodash/lodash/wiki/Build-Differences)
   * [Changelog](https://github.com/lodash/lodash/wiki/Changelog)
-  * [Release Notes](https://github.com/lodash/lodash/releases)
   * [Roadmap](https://github.com/lodash/lodash/wiki/Roadmap)
   * [More Resources](https://github.com/lodash/lodash/wiki/Resources)
 
@@ -66,7 +65,6 @@ lodash is also available in a variety of other builds & module formats.
  * [_.chunk](https://lodash.com/docs#chunk) for splitting an array into chunks of a given size
  * [_.clone](https://lodash.com/docs#clone) supports shallow cloning of `Date` & `RegExp` objects
  * [_.cloneDeep](https://lodash.com/docs#cloneDeep) for deep cloning arrays & objects
- * [_.create](https://lodash.com/docs#create) for easier object inheritance
  * [_.curry](https://lodash.com/docs#curry) & [_.curryRight](https://lodash.com/docs#curryRight) for creating [curried](http://hughfdjackson.com/javascript/why-curry-helps/) functions
  * [_.debounce](https://lodash.com/docs#debounce) & [_.throttle](https://lodash.com/docs#throttle) are cancelable & accept options for more control
  * [_.fill](https://lodash.com/docs#fill) to fill arrays with values
@@ -76,10 +74,12 @@ lodash is also available in a variety of other builds & module formats.
  * [_.forIn](https://lodash.com/docs#forIn) for iterating all enumerable properties
  * [_.forOwn](https://lodash.com/docs#forOwn) for iterating own properties
  * [_.get](https://lodash.com/docs#get) & [_.set](https://lodash.com/docs#set) for deep property getting & setting
+ * [_.gt](https://lodash.com/docs#gt), [_.gte](https://lodash.com/docs#gte), [_.lt](https://lodash.com/docs#lt), & [_.lte](https://lodash.com/docs#lte) relational methods
  * [_.inRange](https://lodash.com/docs#inRange) for checking whether a number is within a given range
  * [_.isNative](https://lodash.com/docs#isNative) to check for native functions
  * [_.isPlainObject](https://lodash.com/docs#isPlainObject) & [_.toPlainObject](https://lodash.com/docs#toPlainObject) to check for & convert to `Object` objects
  * [_.isTypedArray](https://lodash.com/docs#isTypedArray) to check for typed arrays
+ * [_.mapKeys](https://lodash.com/docs#mapKeys) for mapping keys to an object
  * [_.matches](https://lodash.com/docs#matches) supports deep object comparisons
  * [_.matchesProperty](https://lodash.com/docs#matchesProperty) to complement [_.matches](https://lodash.com/docs#matches) & [_.property](https://lodash.com/docs#property)
  * [_.method](https://lodash.com/docs#method) & [_.methodOf](https://lodash.com/docs#methodOf) to create functions that invoke methods
@@ -95,6 +95,7 @@ lodash is also available in a variety of other builds & module formats.
  * [_.support](https://lodash.com/docs#support) for flagging environment features
  * [_.template](https://lodash.com/docs#template) supports [*“imports”*](https://lodash.com/docs#templateSettings-imports) options & [ES template delimiters](http://people.mozilla.org/~jorendorff/es6-draft.html#sec-template-literal-lexical-components)
  * [_.transform](https://lodash.com/docs#transform) as a powerful alternative to [_.reduce](https://lodash.com/docs#reduce) for transforming objects
+ * [_.unzipWith](https://lodash.com/docs#unzipWith) & [_.zipWith](https://lodash.com/docs#zipWith) to specify how grouped values should be combined
  * [_.xor](https://lodash.com/docs#xor) to complement [_.difference](https://lodash.com/docs#difference), [_.intersection](https://lodash.com/docs#intersection), & [_.union](https://lodash.com/docs#union)
  * [_.valuesIn](https://lodash.com/docs#valuesIn) for getting values of all enumerable properties
  * [_.bind](https://lodash.com/docs#bind), [_.curry](https://lodash.com/docs#curry), [_.partial](https://lodash.com/docs#partial), &
@@ -102,17 +103,17 @@ lodash is also available in a variety of other builds & module formats.
  * [_.capitalize](https://lodash.com/docs#capitalize), [_.trim](https://lodash.com/docs#trim), &
    [more](https://lodash.com/docs "_.camelCase, _.deburr, _.endsWith, _.escapeRegExp, _.kebabCase, _.pad, _.padLeft, _.padRight, _.repeat, _.snakeCase, _.startCase, _.startsWith, _.trimLeft, _.trimRight, _.trunc, _.words") string methods
  * [_.clone](https://lodash.com/docs#clone), [_.isEqual](https://lodash.com/docs#isEqual), &
-   [more](https://lodash.com/docs "_.assign, _.cloneDeep, _.merge") accept callbacks
+   [more](https://lodash.com/docs "_.assign, _.cloneDeep, _.merge") accept customizer callbacks
  * [_.dropWhile](https://lodash.com/docs#dropWhile), [_.takeWhile](https://lodash.com/docs#takeWhile), &
-   [more](https://lodash.com/docs "_.drop, _.dropRightWhile, _.take, _.takeRightWhile") to complement [_.first](https://lodash.com/docs#first), [_.initial](https://lodash.com/docs#initial), [_.last](https://lodash.com/docs#last), & [_.rest](https://lodash.com/docs#rest)
+   [more](https://lodash.com/docs "_.drop, _.dropRight, _.dropRightWhile, _.take, _.takeRight, _.takeRightWhile") to complement [_.first](https://lodash.com/docs#first), [_.initial](https://lodash.com/docs#initial), [_.last](https://lodash.com/docs#last), & [_.rest](https://lodash.com/docs#rest)
  * [_.findLast](https://lodash.com/docs#findLast), [_.findLastKey](https://lodash.com/docs#findLastKey), &
-   [more](https://lodash.com/docs "_.flowRight, _.forEachRight, _.forInRight, _.forOwnRight, _.partialRight") right-associative methods
+   [more](https://lodash.com/docs "_.curryRight, _.dropRight, _.dropRightWhile, _.flowRight, _.forEachRight, _.forInRight, _.forOwnRight, _.padRight, partialRight, _.takeRight, _.trimRight, _.takeRightWhile") right-associative methods
  * [_.includes](https://lodash.com/docs#includes), [_.toArray](https://lodash.com/docs#toArray), &
-   [more](https://lodash.com/docs "_.at, _.countBy, _.every, _.filter, _.find, _.findLast, _.forEach, _.forEachRight, _.groupBy, _.indexBy, _.invoke, _.map, _.max, _.min, _.partition, _.pluck, _.reduce, _.reduceRight, _.reject, _.shuffle, _.size, _.some, _.sortBy") accept strings
+   [more](https://lodash.com/docs "_.at, _.countBy, _.every, _.filter, _.find, _.findLast, _.findWhere, _.forEach, _.forEachRight, _.groupBy, _.indexBy, _.invoke, _.map, _.max, _.min, _.partition, _.pluck, _.reduce, _.reduceRight, _.reject, _.shuffle, _.size, _.some, _.sortBy, _.sortByAll, _.sortByOrder, _.sum, _.where") accept strings
  * [_#commit](https://lodash.com/docs#prototype-commit) & [_#plant](https://lodash.com/docs#prototype-plant) for working with chain sequences
  * [_#thru](https://lodash.com/docs#thru) to pass values thru a chain sequence
 
 ## Support
 
-Tested in Chrome 41-42, Firefox 36-37, IE 6-11, Opera 27-28, Safari 5-8, io.js 1.7.1, Node.js 0.8.28, 0.10.38, & 0.12.2, PhantomJS 1.9.8, RingoJS 0.11, & Rhino 1.7RC5.
+Tested in Chrome 41-42, Firefox 37-38, IE 6-11, MS Edge, Opera 28-29, Safari 5-8, ChakraNode 0.12.2, io.js 2.1.0, Node.js 0.8.28, 0.10.38, & 0.12.4, PhantomJS 1.9.8, RingoJS 0.11, & Rhino 1.7.6.
 Automated [browser](https://saucelabs.com/u/lodash) & [CI](https://travis-ci.org/lodash/lodash/) test runs are available. Special thanks to [Sauce Labs](https://saucelabs.com/) for providing automated browser testing.

array.js

@@ -35,8 +35,10 @@ module.exports = {
   'uniq': require('./array/uniq'),
   'unique': require('./array/unique'),
   'unzip': require('./array/unzip'),
+  'unzipWith': require('./array/unzipWith'),
   'without': require('./array/without'),
   'xor': require('./array/xor'),
   'zip': require('./array/zip'),
-  'zipObject': require('./array/zipObject')
+  'zipObject': require('./array/zipObject'),
+  'zipWith': require('./array/zipWith')
 };

array/difference.js

@@ -1,16 +1,12 @@
 var baseDifference = require('../internal/baseDifference'),
     baseFlatten = require('../internal/baseFlatten'),
-    isArguments = require('../lang/isArguments'),
-    isArray = require('../lang/isArray'),
+    isArrayLike = require('../internal/isArrayLike'),
     restParam = require('../function/restParam');
 
 /**
- * Creates an array excluding all values of the provided arrays using
- * `SameValueZero` for equality comparisons.
- *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
+ * Creates an array of unique `array` values not included in the other
+ * provided arrays using [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons.
  *
  * @static
  * @memberOf _
@@ -24,7 +20,7 @@ var baseDifference = require('../internal/baseDifference'),
  * // => [1, 3]
  */
 var difference = restParam(function(array, values) {
-  return (isArray(array) || isArguments(array))
+  return isArrayLike(array)
     ? baseDifference(array, baseFlatten(values, false, true))
     : [];
 });

array/indexOf.js

@@ -6,13 +6,10 @@ var nativeMax = Math.max;
 
 /**
  * Gets the index at which the first occurrence of `value` is found in `array`
- * using `SameValueZero` for equality comparisons. If `fromIndex` is negative,
- * it is used as the offset from the end of `array`. If `array` is sorted
- * providing `true` for `fromIndex` performs a faster binary search.
- *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
+ * using [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons. If `fromIndex` is negative, it is used as the offset
+ * from the end of `array`. If `array` is sorted providing `true` for `fromIndex`
+ * performs a faster binary search.
  *
  * @static
  * @memberOf _

array/intersection.js

@@ -1,17 +1,14 @@
 var baseIndexOf = require('../internal/baseIndexOf'),
     cacheIndexOf = require('../internal/cacheIndexOf'),
     createCache = require('../internal/createCache'),
-    isArguments = require('../lang/isArguments'),
-    isArray = require('../lang/isArray');
+    isArrayLike = require('../internal/isArrayLike'),
+    restParam = require('../function/restParam');
 
 /**
- * Creates an array of unique values in all provided arrays using `SameValueZero`
+ * Creates an array of unique values that are included in all of the provided
+ * arrays using [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
  * for equality comparisons.
  *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
- *
  * @static
  * @memberOf _
  * @category Array
@@ -21,27 +18,19 @@ var baseIndexOf = require('../internal/baseIndexOf'),
  * _.intersection([1, 2], [4, 2], [2, 1]);
  * // => [2]
  */
-function intersection() {
-  var args = [],
-      argsIndex = -1,
-      argsLength = arguments.length,
-      caches = [],
+var intersection = restParam(function(arrays) {
+  var othLength = arrays.length,
+      othIndex = othLength,
+      caches = Array(length),
       indexOf = baseIndexOf,
       isCommon = true,
       result = [];
 
-  while (++argsIndex < argsLength) {
-    var value = arguments[argsIndex];
-    if (isArray(value) || isArguments(value)) {
-      args.push(value);
-      caches.push((isCommon && value.length >= 120) ? createCache(argsIndex && value) : null);
-    }
+  while (othIndex--) {
+    var value = arrays[othIndex] = isArrayLike(value = arrays[othIndex]) ? value : [];
+    caches[othIndex] = (isCommon && value.length >= 120) ? createCache(othIndex && value) : null;
   }
-  argsLength = args.length;
-  if (argsLength < 2) {
-    return result;
-  }
-  var array = args[0],
+  var array = arrays[0],
       index = -1,
       length = array ? array.length : 0,
       seen = caches[0];
@@ -50,10 +39,10 @@ function intersection() {
   while (++index < length) {
     value = array[index];
     if ((seen ? cacheIndexOf(seen, value) : indexOf(result, value, 0)) < 0) {
-      argsIndex = argsLength;
-      while (--argsIndex) {
-        var cache = caches[argsIndex];
-        if ((cache ? cacheIndexOf(cache, value) : indexOf(args[argsIndex], value, 0)) < 0) {
+      var othIndex = othLength;
+      while (--othIndex) {
+        var cache = caches[othIndex];
+        if ((cache ? cacheIndexOf(cache, value) : indexOf(arrays[othIndex], value, 0)) < 0) {
           continue outer;
         }
       }
@@ -64,6 +53,6 @@ function intersection() {
     }
   }
   return result;
-}
+});
 
 module.exports = intersection;

array/pull.js

@@ -7,14 +7,11 @@ var arrayProto = Array.prototype;
 var splice = arrayProto.splice;
 
 /**
- * Removes all provided values from `array` using `SameValueZero` for equality
- * comparisons.
+ * Removes all provided values from `array` using
+ * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons.
  *
- * **Notes:**
- *  - Unlike `_.without`, this method mutates `array`
- *  - [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- *    comparisons are like strict equality comparisons, e.g. `===`, except
- *    that `NaN` matches `NaN`
+ * **Note:** Unlike `_.without`, this method mutates `array`.
  *
  * @static
  * @memberOf _

array/pullAt.js

@@ -30,7 +30,6 @@ var baseAt = require('../internal/baseAt'),
  * // => [10, 20]
  */
 var pullAt = restParam(function(array, indexes) {
-  array || (array = []);
   indexes = baseFlatten(indexes);
 
   var result = baseAt(array, indexes);

array/union.js

@@ -3,12 +3,9 @@ var baseFlatten = require('../internal/baseFlatten'),
     restParam = require('../function/restParam');
 
 /**
- * Creates an array of unique values, in order, of the provided arrays using
- * `SameValueZero` for equality comparisons.
- *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
+ * Creates an array of unique values, in order, from all of the provided arrays
+ * using [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons.
  *
  * @static
  * @memberOf _

array/uniq.js

@@ -4,8 +4,9 @@ var baseCallback = require('../internal/baseCallback'),
     sortedUniq = require('../internal/sortedUniq');
 
 /**
- * Creates a duplicate-free version of an array, using `SameValueZero` for
- * equality comparisons, in which only the first occurence of each element
+ * Creates a duplicate-free version of an array, using
+ * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons, in which only the first occurence of each element
  * is kept. Providing `true` for `isSorted` performs a faster search algorithm
  * for sorted arrays. If an iteratee function is provided it is invoked for
  * each element in the array to generate the criterion by which uniqueness
@@ -23,10 +24,6 @@ var baseCallback = require('../internal/baseCallback'),
  * callback returns `true` for elements that have the properties of the given
  * object, else `false`.
  *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
- *
  * @static
  * @memberOf _
  * @alias unique

array/unzip.js

@@ -1,11 +1,14 @@
-var arrayMap = require('../internal/arrayMap'),
-    arrayMax = require('../internal/arrayMax'),
+var arrayFilter = require('../internal/arrayFilter'),
+    arrayMap = require('../internal/arrayMap'),
     baseProperty = require('../internal/baseProperty'),
-    getLength = require('../internal/getLength');
+    isArrayLike = require('../internal/isArrayLike');
+
+/* Native method references for those with the same name as other `lodash` methods. */
+var nativeMax = Math.max;
 
 /**
  * This method is like `_.zip` except that it accepts an array of grouped
- * elements and creates an array regrouping the elements to their pre-`_.zip`
+ * elements and creates an array regrouping the elements to their pre-zip
  * configuration.
  *
  * @static
@@ -22,10 +25,19 @@ var arrayMap = require('../internal/arrayMap'),
  * // => [['fred', 'barney'], [30, 40], [true, false]]
  */
 function unzip(array) {
+  if (!(array && array.length)) {
+    return [];
+  }
   var index = -1,
-      length = (array && array.length && arrayMax(arrayMap(array, getLength))) >>> 0,
-      result = Array(length);
+      length = 0;
 
+  array = arrayFilter(array, function(group) {
+    if (isArrayLike(group)) {
+      length = nativeMax(group.length, length);
+      return true;
+    }
+  });
+  var result = Array(length);
   while (++index < length) {
     result[index] = arrayMap(array, baseProperty(index));
   }

array/unzipWith.js

@@ -0,0 +1,41 @@
+var arrayMap = require('../internal/arrayMap'),
+    arrayReduce = require('../internal/arrayReduce'),
+    bindCallback = require('../internal/bindCallback'),
+    unzip = require('./unzip');
+
+/**
+ * This method is like `_.unzip` except that it accepts an iteratee to specify
+ * how regrouped values should be combined. The `iteratee` is bound to `thisArg`
+ * and invoked with four arguments: (accumulator, value, index, group).
+ *
+ * @static
+ * @memberOf _
+ * @category Array
+ * @param {Array} array The array of grouped elements to process.
+ * @param {Function} [iteratee] The function to combine regrouped values.
+ * @param {*} [thisArg] The `this` binding of `iteratee`.
+ * @returns {Array} Returns the new array of regrouped elements.
+ * @example
+ *
+ * var zipped = _.zip([1, 2], [10, 20], [100, 200]);
+ * // => [[1, 10, 100], [2, 20, 200]]
+ *
+ * _.unzipWith(zipped, _.add);
+ * // => [3, 30, 300]
+ */
+function unzipWith(array, iteratee, thisArg) {
+  var length = array ? array.length : 0;
+  if (!length) {
+    return [];
+  }
+  var result = unzip(array);
+  if (iteratee == null) {
+    return result;
+  }
+  iteratee = bindCallback(iteratee, thisArg, 4);
+  return arrayMap(result, function(group) {
+    return arrayReduce(group, iteratee, undefined, true);
+  });
+}
+
+module.exports = unzipWith;

array/without.js

@@ -1,15 +1,11 @@
 var baseDifference = require('../internal/baseDifference'),
-    isArguments = require('../lang/isArguments'),
-    isArray = require('../lang/isArray'),
+    isArrayLike = require('../internal/isArrayLike'),
     restParam = require('../function/restParam');
 
 /**
- * Creates an array excluding all provided values using `SameValueZero` for
- * equality comparisons.
- *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
+ * Creates an array excluding all provided values using
+ * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons.
  *
  * @static
  * @memberOf _
@@ -23,7 +19,7 @@ var baseDifference = require('../internal/baseDifference'),
  * // => [3]
  */
 var without = restParam(function(array, values) {
-  return (isArray(array) || isArguments(array))
+  return isArrayLike(array)
     ? baseDifference(array, values)
     : [];
 });

array/xor.js

@@ -1,10 +1,9 @@
 var baseDifference = require('../internal/baseDifference'),
     baseUniq = require('../internal/baseUniq'),
-    isArguments = require('../lang/isArguments'),
-    isArray = require('../lang/isArray');
+    isArrayLike = require('../internal/isArrayLike');
 
 /**
- * Creates an array that is the [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference)
+ * Creates an array of unique values that is the [symmetric difference](https://en.wikipedia.org/wiki/Symmetric_difference)
  * of the provided arrays.
  *
  * @static
@@ -23,7 +22,7 @@ function xor() {
 
   while (++index < length) {
     var array = arguments[index];
-    if (isArray(array) || isArguments(array)) {
+    if (isArrayLike(array)) {
       var result = result
         ? baseDifference(result, array).concat(baseDifference(array, result))
         : array;

array/zipWith.js

@@ -0,0 +1,36 @@
+var restParam = require('../function/restParam'),
+    unzipWith = require('./unzipWith');
+
+/**
+ * This method is like `_.zip` except that it accepts an iteratee to specify
+ * how grouped values should be combined. The `iteratee` is bound to `thisArg`
+ * and invoked with four arguments: (accumulator, value, index, group).
+ *
+ * @static
+ * @memberOf _
+ * @category Array
+ * @param {...Array} [arrays] The arrays to process.
+ * @param {Function} [iteratee] The function to combine grouped values.
+ * @param {*} [thisArg] The `this` binding of `iteratee`.
+ * @returns {Array} Returns the new array of grouped elements.
+ * @example
+ *
+ * _.zipWith([1, 2], [10, 20], [100, 200], _.add);
+ * // => [111, 222]
+ */
+var zipWith = restParam(function(arrays) {
+  var length = arrays.length,
+      iteratee = length > 2 ? arrays[length - 2] : undefined,
+      thisArg = length > 1 ? arrays[length - 1] : undefined;
+
+  if (length > 2 && typeof iteratee == 'function') {
+    length -= 2;
+  } else {
+    iteratee = (length > 1 && typeof thisArg == 'function') ? (--length, thisArg) : undefined;
+    thisArg = undefined;
+  }
+  arrays.length = length;
+  return unzipWith(arrays, iteratee, thisArg);
+});
+
+module.exports = zipWith;

chain/lodash.js

@@ -50,30 +50,31 @@ var hasOwnProperty = objectProto.hasOwnProperty;
  * `filter`, `flatten`, `flattenDeep`, `flow`, `flowRight`, `forEach`,
  * `forEachRight`, `forIn`, `forInRight`, `forOwn`, `forOwnRight`, `functions`,
  * `groupBy`, `indexBy`, `initial`, `intersection`, `invert`, `invoke`, `keys`,
- * `keysIn`, `map`, `mapValues`, `matches`, `matchesProperty`, `memoize`,
- * `merge`, `mixin`, `negate`, `omit`, `once`, `pairs`, `partial`, `partialRight`,
- * `partition`, `pick`, `plant`, `pluck`, `property`, `propertyOf`, `pull`,
- * `pullAt`, `push`, `range`, `rearg`, `reject`, `remove`, `rest`, `reverse`,
- * `shuffle`, `slice`, `sort`, `sortBy`, `sortByAll`, `sortByOrder`, `splice`,
- * `spread`, `take`, `takeRight`, `takeRightWhile`, `takeWhile`, `tap`,
- * `throttle`, `thru`, `times`, `toArray`, `toPlainObject`, `transform`,
- * `union`, `uniq`, `unshift`, `unzip`, `values`, `valuesIn`, `where`,
- * `without`, `wrap`, `xor`, `zip`, and `zipObject`
+ * `keysIn`, `map`, `mapKeys`, `mapValues`, `matches`, `matchesProperty`,
+ * `memoize`, `merge`, `method`, `methodOf`, `mixin`, `negate`, `omit`, `once`,
+ * `pairs`, `partial`, `partialRight`, `partition`, `pick`, `plant`, `pluck`,
+ * `property`, `propertyOf`, `pull`, `pullAt`, `push`, `range`, `rearg`,
+ * `reject`, `remove`, `rest`, `restParam`, `reverse`, `set`, `shuffle`,
+ * `slice`, `sort`, `sortBy`, `sortByAll`, `sortByOrder`, `splice`, `spread`,
+ * `take`, `takeRight`, `takeRightWhile`, `takeWhile`, `tap`, `throttle`,
+ * `thru`, `times`, `toArray`, `toPlainObject`, `transform`, `union`, `uniq`,
+ * `unshift`, `unzip`, `unzipWith`, `values`, `valuesIn`, `where`, `without`,
+ * `wrap`, `xor`, `zip`, `zipObject`, `zipWith`
  *
  * The wrapper methods that are **not** chainable by default are:
  * `add`, `attempt`, `camelCase`, `capitalize`, `clone`, `cloneDeep`, `deburr`,
  * `endsWith`, `escape`, `escapeRegExp`, `every`, `find`, `findIndex`, `findKey`,
- * `findLast`, `findLastIndex`, `findLastKey`, `findWhere`, `first`, `has`,
- * `identity`, `includes`, `indexOf`, `inRange`, `isArguments`, `isArray`,
- * `isBoolean`, `isDate`, `isElement`, `isEmpty`, `isEqual`, `isError`, `isFinite`
- * `isFunction`, `isMatch`, `isNative`, `isNaN`, `isNull`, `isNumber`, `isObject`,
- * `isPlainObject`, `isRegExp`, `isString`, `isUndefined`, `isTypedArray`,
- * `join`, `kebabCase`, `last`, `lastIndexOf`, `max`, `min`, `noConflict`,
- * `noop`, `now`, `pad`, `padLeft`, `padRight`, `parseInt`, `pop`, `random`,
- * `reduce`, `reduceRight`, `repeat`, `result`, `runInContext`, `shift`, `size`,
- * `snakeCase`, `some`, `sortedIndex`, `sortedLastIndex`, `startCase`, `startsWith`,
- * `sum`, `template`, `trim`, `trimLeft`, `trimRight`, `trunc`, `unescape`,
- * `uniqueId`, `value`, and `words`
+ * `findLast`, `findLastIndex`, `findLastKey`, `findWhere`, `first`, `get`,
+ * `gt`, `gte`, `has`, `identity`, `includes`, `indexOf`, `inRange`, `isArguments`,
+ * `isArray`, `isBoolean`, `isDate`, `isElement`, `isEmpty`, `isEqual`, `isError`,
+ * `isFinite` `isFunction`, `isMatch`, `isNative`, `isNaN`, `isNull`, `isNumber`,
+ * `isObject`, `isPlainObject`, `isRegExp`, `isString`, `isUndefined`,
+ * `isTypedArray`, `join`, `kebabCase`, `last`, `lastIndexOf`, `lt`, `lte`,
+ * `max`, `min`, `noConflict`, `noop`, `now`, `pad`, `padLeft`, `padRight`,
+ * `parseInt`, `pop`, `random`, `reduce`, `reduceRight`, `repeat`, `result`,
+ * `runInContext`, `shift`, `size`, `snakeCase`, `some`, `sortedIndex`,
+ * `sortedLastIndex`, `startCase`, `startsWith`, `sum`, `template`, `trim`,
+ * `trimLeft`, `trimRight`, `trunc`, `unescape`, `uniqueId`, `value`, and `words`
  *
  * The wrapper method `sample` will return a wrapped value when `n` is provided,
  * otherwise an unwrapped value is returned.

collection/at.js

@@ -1,9 +1,6 @@
 var baseAt = require('../internal/baseAt'),
     baseFlatten = require('../internal/baseFlatten'),
-    getLength = require('../internal/getLength'),
-    isLength = require('../internal/isLength'),
-    restParam = require('../function/restParam'),
-    toIterable = require('../internal/toIterable');
+    restParam = require('../function/restParam');
 
 /**
  * Creates an array of elements corresponding to the given keys, or indexes,
@@ -26,10 +23,6 @@ var baseAt = require('../internal/baseAt'),
  * // => ['barney', 'pebbles']
  */
 var at = restParam(function(collection, props) {
-  var length = collection ? getLength(collection) : 0;
-  if (isLength(length)) {
-    collection = toIterable(collection);
-  }
   return baseAt(collection, baseFlatten(props));
 });
 

collection/includes.js

@@ -10,13 +10,10 @@ var baseIndexOf = require('../internal/baseIndexOf'),
 var nativeMax = Math.max;
 
 /**
- * Checks if `value` is in `collection` using `SameValueZero` for equality
- * comparisons. If `fromIndex` is negative, it is used as the offset from
- * the end of `collection`.
- *
- * **Note:** [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
- * comparisons are like strict equality comparisons, e.g. `===`, except that
- * `NaN` matches `NaN`.
+ * Checks if `value` is in `collection` using
+ * [`SameValueZero`](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-samevaluezero)
+ * for equality comparisons. If `fromIndex` is negative, it is used as the offset
+ * from the end of `collection`.
  *
  * @static
  * @memberOf _

collection/invoke.js

@@ -1,12 +1,11 @@
 var baseEach = require('../internal/baseEach'),
-    getLength = require('../internal/getLength'),
     invokePath = require('../internal/invokePath'),
+    isArrayLike = require('../internal/isArrayLike'),
     isKey = require('../internal/isKey'),
-    isLength = require('../internal/isLength'),
     restParam = require('../function/restParam');
 
 /**
- * Invokes the method at `path` on each element in `collection`, returning
+ * Invokes the method at `path` of each element in `collection`, returning
  * an array of the results of each invoked method. Any additional arguments
  * are provided to each invoked method. If `methodName` is a function it is
  * invoked for, and `this` bound to, each element in `collection`.
@@ -31,11 +30,10 @@ var invoke = restParam(function(collection, path, args) {
   var index = -1,
       isFunc = typeof path == 'function',
       isProp = isKey(path),
-      length = getLength(collection),
-      result = isLength(length) ? Array(length) : [];
+      result = isArrayLike(collection) ? Array(collection.length) : [];
 
   baseEach(collection, function(value) {
-    var func = isFunc ? path : (isProp && value != null && value[path]);
+    var func = isFunc ? path : ((isProp && value != null) ? value[path] : null);
     result[++index] = func ? func.apply(value, args) : invokePath(value, path, args);
   });
   return result;

collection/map.js

@@ -19,14 +19,15 @@ var arrayMap = require('../internal/arrayMap'),
  * callback returns `true` for elements that have the properties of the given
  * object, else `false`.
  *
- * Many lodash methods are guarded to work as interatees for methods like
+ * Many lodash methods are guarded to work as iteratees for methods like
  * `_.every`, `_.filter`, `_.map`, `_.mapValues`, `_.reject`, and `_.some`.
  *
  * The guarded methods are:
- * `ary`, `callback`, `chunk`, `clone`, `create`, `curry`, `curryRight`, `drop`,
- * `dropRight`, `every`, `fill`, `flatten`, `invert`, `max`, `min`, `parseInt`,
- * `slice`, `sortBy`, `take`, `takeRight`, `template`, `trim`, `trimLeft`,
- * `trimRight`, `trunc`, `random`, `range`, `sample`, `some`, `uniq`, and `words`
+ * `ary`, `callback`, `chunk`, `clone`, `create`, `curry`, `curryRight`,
+ * `drop`, `dropRight`, `every`, `fill`, `flatten`, `invert`, `max`, `min`,
+ * `parseInt`, `slice`, `sortBy`, `take`, `takeRight`, `template`, `trim`,
+ * `trimLeft`, `trimRight`, `trunc`, `random`, `range`, `sample`, `some`,
+ * `sum`, `uniq`, and `words`
  *
  * @static
  * @memberOf _

collection/reduce.js

@@ -10,7 +10,7 @@ var arrayReduce = require('../internal/arrayReduce'),
  * value. The `iteratee` is bound to `thisArg` and invoked with four arguments:
  * (accumulator, value, index|key, collection).
  *
- * Many lodash methods are guarded to work as interatees for methods like
+ * Many lodash methods are guarded to work as iteratees for methods like
  * `_.reduce`, `_.reduceRight`, and `_.transform`.
  *
  * The guarded methods are:

collection/reduceRight.js

@@ -24,6 +24,6 @@ var arrayReduceRight = require('../internal/arrayReduceRight'),
  * }, []);
  * // => [4, 5, 2, 3, 0, 1]
  */
-var reduceRight =  createReduce(arrayReduceRight, baseEachRight);
+var reduceRight = createReduce(arrayReduceRight, baseEachRight);
 
 module.exports = reduceRight;

collection/reject.js

@@ -7,17 +7,6 @@ var arrayFilter = require('../internal/arrayFilter'),
  * The opposite of `_.filter`; this method returns the elements of `collection`
  * that `predicate` does **not** return truthy for.
  *
- * If a property name is provided for `predicate` the created `_.property`
- * style callback returns the property value of the given element.
- *
- * If a value is also provided for `thisArg` the created `_.matchesProperty`
- * style callback returns `true` for elements that have a matching property
- * value, else `false`.
- *
- * If an object is provided for `predicate` the created `_.matches` style
- * callback returns `true` for elements that have the properties of the given
- * object, else `false`.
- *
  * @static
  * @memberOf _
  * @category Collection

collection/sample.js

@@ -1,6 +1,6 @@
 var baseRandom = require('../internal/baseRandom'),
     isIterateeCall = require('../internal/isIterateeCall'),
-    shuffle = require('./shuffle'),
+    toArray = require('../lang/toArray'),
     toIterable = require('../internal/toIterable');
 
 /* Native method references for those with the same name as other `lodash` methods. */
@@ -30,8 +30,20 @@ function sample(collection, n, guard) {
     var length = collection.length;
     return length > 0 ? collection[baseRandom(0, length - 1)] : undefined;
   }
-  var result = shuffle(collection);
-  result.length = nativeMin(n < 0 ? 0 : (+n || 0), result.length);
+  var index = -1,
+      result = toArray(collection),
+      length = result.length,
+      lastIndex = length - 1;
+
+  n = nativeMin(n < 0 ? 0 : (+n || 0), length);
+  while (++index < n) {
+    var rand = baseRandom(index, lastIndex),
+        value = result[rand];
+
+    result[rand] = result[index];
+    result[index] = value;
+  }
+  result.length = n;
   return result;
 }
 

collection/shuffle.js

@@ -1,5 +1,7 @@
-var baseRandom = require('../internal/baseRandom'),
-    toIterable = require('../internal/toIterable');
+var sample = require('./sample');
+
+/** Used as references for `-Infinity` and `Infinity`. */
+var POSITIVE_INFINITY = Number.POSITIVE_INFINITY;
 
 /**
  * Creates an array of shuffled values, using a version of the
@@ -16,20 +18,7 @@ var baseRandom = require('../internal/baseRandom'),
  * // => [4, 1, 3, 2]
  */
 function shuffle(collection) {
-  collection = toIterable(collection);
-
-  var index = -1,
-      length = collection.length,
-      result = Array(length);
-
-  while (++index < length) {
-    var rand = baseRandom(0, index);
-    if (index != rand) {
-      result[index] = result[rand];
-    }
-    result[rand] = collection[index];
-  }
-  return result;
+  return sample(collection, POSITIVE_INFINITY);
 }
 
 module.exports = shuffle;

date/now.js

@@ -1,7 +1,7 @@
-var isNative = require('../lang/isNative');
+var getNative = require('../internal/getNative');
 
 /* Native method references for those with the same name as other `lodash` methods. */
-var nativeNow = isNative(nativeNow = Date.now) && nativeNow;
+var nativeNow = getNative(Date, 'now');
 
 /**
  * Gets the number of milliseconds that have elapsed since the Unix epoch

function/debounce.js

@@ -8,12 +8,13 @@ var FUNC_ERROR_TEXT = 'Expected a function';
 var nativeMax = Math.max;
 
 /**
- * Creates a function that delays invoking `func` until after `wait` milliseconds
- * have elapsed since the last time it was invoked. The created function comes
- * with a `cancel` method to cancel delayed invocations. Provide an options
- * object to indicate that `func` should be invoked on the leading and/or
- * trailing edge of the `wait` timeout. Subsequent calls to the debounced
- * function return the result of the last `func` invocation.
+ * Creates a debounced function that delays invoking `func` until after `wait`
+ * milliseconds have elapsed since the last time the debounced function was
+ * invoked. The debounced function comes with a `cancel` method to cancel
+ * delayed invocations. Provide an options object to indicate that `func`
+ * should be invoked on the leading and/or trailing edge of the `wait` timeout.
+ * Subsequent calls to the debounced function return the result of the last
+ * `func` invocation.
  *
  * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
  * on the trailing edge of the timeout only if the the debounced function is

function/memoize.js

@@ -60,14 +60,14 @@ function memoize(func, resolver) {
   }
   var memoized = function() {
     var args = arguments,
-        cache = memoized.cache,
-        key = resolver ? resolver.apply(this, args) : args[0];
+        key = resolver ? resolver.apply(this, args) : args[0],
+        cache = memoized.cache;
 
     if (cache.has(key)) {
       return cache.get(key);
     }
     var result = func.apply(this, args);
-    cache.set(key, result);
+    memoized.cache = cache.set(key, result);
     return result;
   };
   memoized.cache = new memoize.Cache;

function/throttle.js

@@ -12,12 +12,12 @@ var debounceOptions = {
 };
 
 /**
- * Creates a function that only invokes `func` at most once per every `wait`
- * milliseconds. The created function comes with a `cancel` method to cancel
- * delayed invocations. Provide an options object to indicate that `func`
- * should be invoked on the leading and/or trailing edge of the `wait` timeout.
- * Subsequent calls to the throttled function return the result of the last
- * `func` call.
+ * Creates a throttled function that only invokes `func` at most once per
+ * every `wait` milliseconds. The throttled function comes with a `cancel`
+ * method to cancel delayed invocations. Provide an options object to indicate
+ * that `func` should be invoked on the leading and/or trailing edge of the
+ * `wait` timeout. Subsequent calls to the throttled function return the
+ * result of the last `func` call.
  *
  * **Note:** If `leading` and `trailing` options are `true`, `func` is invoked
  * on the trailing edge of the timeout only if the the throttled function is

internal/SetCache.js

@@ -1,11 +1,11 @@
 var cachePush = require('./cachePush'),
-    isNative = require('../lang/isNative');
+    getNative = require('./getNative');
 
 /** Native method references. */
-var Set = isNative(Set = global.Set) && Set;
+var Set = getNative(global, 'Set');
 
 /* Native method references for those with the same name as other `lodash` methods. */
-var nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate;
+var nativeCreate = getNative(Object, 'create');
 
 /**
  *

internal/arrayExtremum.js

@@ -0,0 +1,30 @@
+/**
+ * A specialized version of `baseExtremum` for arrays which invokes `iteratee`
+ * with one argument: (value).
+ *
+ * @private
+ * @param {Array} array The array to iterate over.
+ * @param {Function} iteratee The function invoked per iteration.
+ * @param {Function} comparator The function used to compare values.
+ * @param {*} exValue The initial extremum value.
+ * @returns {*} Returns the extremum value.
+ */
+function arrayExtremum(array, iteratee, comparator, exValue) {
+  var index = -1,
+      length = array.length,
+      computed = exValue,
+      result = computed;
+
+  while (++index < length) {
+    var value = array[index],
+        current = +iteratee(value);
+
+    if (comparator(current, computed)) {
+      computed = current;
+      result = value;
+    }
+  }
+  return result;
+}
+
+module.exports = arrayExtremum;

internal/arrayMax.js

@@ -1,25 +0,0 @@
-/** Used as references for `-Infinity` and `Infinity`. */
-var NEGATIVE_INFINITY = Number.NEGATIVE_INFINITY;
-
-/**
- * A specialized version of `_.max` for arrays without support for iteratees.
- *
- * @private
- * @param {Array} array The array to iterate over.
- * @returns {*} Returns the maximum value.
- */
-function arrayMax(array) {
-  var index = -1,
-      length = array.length,
-      result = NEGATIVE_INFINITY;
-
-  while (++index < length) {
-    var value = array[index];
-    if (value > result) {
-      result = value;
-    }
-  }
-  return result;
-}
-
-module.exports = arrayMax;

internal/arrayMin.js

@@ -1,25 +0,0 @@
-/** Used as references for `-Infinity` and `Infinity`. */
-var POSITIVE_INFINITY = Number.POSITIVE_INFINITY;
-
-/**
- * A specialized version of `_.min` for arrays without support for iteratees.
- *
- * @private
- * @param {Array} array The array to iterate over.
- * @returns {*} Returns the minimum value.
- */
-function arrayMin(array) {
-  var index = -1,
-      length = array.length,
-      result = POSITIVE_INFINITY;
-
-  while (++index < length) {
-    var value = array[index];
-    if (value < result) {
-      result = value;
-    }
-  }
-  return result;
-}
-
-module.exports = arrayMin;

internal/assignWith.js

@@ -1,11 +1,4 @@
-var getSymbols = require('./getSymbols'),
-    keys = require('../object/keys');
-
-/** Used for native method references. */
-var arrayProto = Array.prototype;
-
-/** Native method references. */
-var push = arrayProto.push;
+var keys = require('../object/keys');
 
 /**
  * A specialized version of `_.assign` for customizing assigned values without
@@ -19,10 +12,8 @@ var push = arrayProto.push;
  * @returns {Object} Returns `object`.
  */
 function assignWith(object, source, customizer) {
-  var props = keys(source);
-  push.apply(props, getSymbols(source));
-
   var index = -1,
+      props = keys(source),
       length = props.length;
 
   while (++index < length) {

internal/baseAssign.js

@@ -1,27 +1,6 @@
 var baseCopy = require('./baseCopy'),
-    getSymbols = require('./getSymbols'),
-    isNative = require('../lang/isNative'),
     keys = require('../object/keys');
 
-/** Native method references. */
-var preventExtensions = isNative(Object.preventExtensions = Object.preventExtensions) && preventExtensions;
-
-/** Used as `baseAssign`. */
-var nativeAssign = (function() {
-  // Avoid `Object.assign` in Firefox 34-37 which have an early implementation
-  // with a now defunct try/catch behavior. See https://bugzilla.mozilla.org/show_bug.cgi?id=1103344
-  // for more details.
-  //
-  // Use `Object.preventExtensions` on a plain object instead of simply using
-  // `Object('x')` because Chrome and IE fail to throw an error when attempting
-  // to assign values to readonly indexes of strings in strict mode.
-  var object = { '1': 0 },
-      func = preventExtensions && isNative(func = Object.assign) && func;
-
-  try { func(preventExtensions(object), 'xo'); } catch(e) {}
-  return !object[1] && func;
-}());
-
 /**
  * The base implementation of `_.assign` without support for argument juggling,
  * multiple sources, and `customizer` functions.
@@ -31,10 +10,10 @@ var nativeAssign = (function() {
  * @param {Object} source The source object.
  * @returns {Object} Returns `object`.
  */
-var baseAssign = nativeAssign || function(object, source) {
+function baseAssign(object, source) {
   return source == null
     ? object
-    : baseCopy(source, getSymbols(source), baseCopy(source, keys(source), object));
-};
+    : baseCopy(source, keys(source), object);
+}
 
 module.exports = baseAssign;

internal/baseAt.js

@@ -1,5 +1,5 @@
-var isIndex = require('./isIndex'),
-    isLength = require('./isLength');
+var isArrayLike = require('./isArrayLike'),
+    isIndex = require('./isIndex');
 
 /**
  * The base implementation of `_.at` without support for string collections
@@ -12,8 +12,9 @@ var isIndex = require('./isIndex'),
  */
 function baseAt(collection, props) {
   var index = -1,
-      length = collection.length,
-      isArr = isLength(length),
+      isNil = collection == null,
+      isArr = !isNil && isArrayLike(collection),
+      length = isArr ? collection.length : 0,
       propsLength = props.length,
       result = Array(propsLength);
 
@@ -22,7 +23,7 @@ function baseAt(collection, props) {
     if (isArr) {
       result[index] = isIndex(key, length) ? collection[key] : undefined;
     } else {
-      result[index] = collection[key];
+      result[index] = isNil ? undefined : collection[key];
     }
   }
   return result;

internal/baseCompareAscending.js

@@ -3,19 +3,28 @@
  * sorts them in ascending order without guaranteeing a stable sort.
  *
  * @private
- * @param {*} value The value to compare to `other`.
- * @param {*} other The value to compare to `value`.
+ * @param {*} value The value to compare.
+ * @param {*} other The other value to compare.
  * @returns {number} Returns the sort order indicator for `value`.
  */
 function baseCompareAscending(value, other) {
   if (value !== other) {
-    var valIsReflexive = value === value,
+    var valIsNull = value === null,
+        valIsUndef = value === undefined,
+        valIsReflexive = value === value;
+
+    var othIsNull = other === null,
+        othIsUndef = other === undefined,
         othIsReflexive = other === other;
 
-    if (value > other || !valIsReflexive || (value === undefined && othIsReflexive)) {
+    if ((value > other && !othIsNull) || !valIsReflexive ||
+        (valIsNull && !othIsUndef && othIsReflexive) ||
+        (valIsUndef && othIsReflexive)) {
       return 1;
     }
-    if (value < other || !othIsReflexive || (other === undefined && valIsReflexive)) {
+    if ((value < other && !valIsNull) || !othIsReflexive ||
+        (othIsNull && !valIsUndef && valIsReflexive) ||
+        (othIsUndef && valIsReflexive)) {
       return -1;
     }
   }

internal/baseCreate.js

@@ -9,14 +9,14 @@ var isObject = require('../lang/isObject');
  * @returns {Object} Returns the new object.
  */
 var baseCreate = (function() {
-  function Object() {}
+  function object() {}
   return function(prototype) {
     if (isObject(prototype)) {
-      Object.prototype = prototype;
-      var result = new Object;
-      Object.prototype = null;
+      object.prototype = prototype;
+      var result = new object;
+      object.prototype = null;
     }
-    return result || global.Object();
+    return result || {};
   };
 }());
 

internal/baseExtremum.js

@@ -1,30 +1,24 @@
 var baseEach = require('./baseEach');
 
-/** Used as references for `-Infinity` and `Infinity`. */
-var NEGATIVE_INFINITY = Number.NEGATIVE_INFINITY,
-    POSITIVE_INFINITY = Number.POSITIVE_INFINITY;
-
 /**
  * Gets the extremum value of `collection` invoking `iteratee` for each value
  * in `collection` to generate the criterion by which the value is ranked.
- * The `iteratee` is invoked with three arguments: (value, index, collection).
+ * The `iteratee` is invoked with three arguments: (value, index|key, collection).
  *
  * @private
  * @param {Array|Object|string} collection The collection to iterate over.
  * @param {Function} iteratee The function invoked per iteration.
- * @param {boolean} [isMin] Specify returning the minimum, instead of the
- *  maximum, extremum value.
+ * @param {Function} comparator The function used to compare values.
+ * @param {*} exValue The initial extremum value.
  * @returns {*} Returns the extremum value.
  */
-function extremumBy(collection, iteratee, isMin) {
-  var exValue = isMin ? POSITIVE_INFINITY : NEGATIVE_INFINITY,
-      computed = exValue,
+function baseExtremum(collection, iteratee, comparator, exValue) {
+  var computed = exValue,
       result = computed;
 
   baseEach(collection, function(value, index, collection) {
-    var current = iteratee(value, index, collection);
-    if ((isMin ? (current < computed) : (current > computed)) ||
-        (current === exValue && current === result)) {
+    var current = +iteratee(value, index, collection);
+    if (comparator(current, computed) || (current === exValue && current === result)) {
       computed = current;
       result = value;
     }
@@ -32,4 +26,4 @@ function extremumBy(collection, iteratee, isMin) {
   return result;
 }
 
-module.exports = extremumBy;
+module.exports = baseExtremum;

internal/baseFlatten.js

@@ -1,6 +1,6 @@
 var isArguments = require('../lang/isArguments'),
     isArray = require('../lang/isArray'),
-    isLength = require('./isLength'),
+    isArrayLike = require('./isArrayLike'),
     isObjectLike = require('./isObjectLike');
 
 /**
@@ -9,8 +9,8 @@ var isArguments = require('../lang/isArguments'),
  *
  * @private
  * @param {Array} array The array to flatten.
- * @param {boolean} isDeep Specify a deep flatten.
- * @param {boolean} isStrict Restrict flattening to arrays and `arguments` objects.
+ * @param {boolean} [isDeep] Specify a deep flatten.
+ * @param {boolean} [isStrict] Restrict flattening to arrays-like objects.
  * @returns {Array} Returns the new flattened array.
  */
 function baseFlatten(array, isDeep, isStrict) {
@@ -21,8 +21,8 @@ function baseFlatten(array, isDeep, isStrict) {
 
   while (++index < length) {
     var value = array[index];
-
-    if (isObjectLike(value) && isLength(value.length) && (isArray(value) || isArguments(value))) {
+    if (isObjectLike(value) && isArrayLike(value) &&
+        (isStrict || isArray(value) || isArguments(value))) {
       if (isDeep) {
         // Recursively flatten arrays (susceptible to call stack limits).
         value = baseFlatten(value, isDeep, isStrict);
@@ -30,7 +30,6 @@ function baseFlatten(array, isDeep, isStrict) {
       var valIndex = -1,
           valLength = value.length;
 
-      result.length += valLength;
       while (++valIndex < valLength) {
         result[++resIndex] = value[valIndex];
       }

internal/baseGet.js

@@ -17,13 +17,13 @@ function baseGet(object, path, pathKey) {
   if (pathKey !== undefined && pathKey in toObject(object)) {
     path = [pathKey];
   }
-  var index = -1,
+  var index = 0,
       length = path.length;
 
-  while (object != null && ++index < length) {
-    var result = object = object[path[index]];
+  while (object != null && index < length) {
+    object = object[path[index++]];
   }
-  return result;
+  return (index && index == length) ? object : undefined;
 }
 
 module.exports = baseGet;

internal/baseIsEqual.js

@@ -1,4 +1,6 @@
-var baseIsEqualDeep = require('./baseIsEqualDeep');
+var baseIsEqualDeep = require('./baseIsEqualDeep'),
+    isObject = require('../lang/isObject'),
+    isObjectLike = require('./isObjectLike');
 
 /**
  * The base implementation of `_.isEqual` without support for `this` binding
@@ -14,18 +16,10 @@ var baseIsEqualDeep = require('./baseIsEqualDeep');
  * @returns {boolean} Returns `true` if the values are equivalent, else `false`.
  */
 function baseIsEqual(value, other, customizer, isLoose, stackA, stackB) {
-  // Exit early for identical values.
   if (value === other) {
-    // Treat `+0` vs. `-0` as not equal.
-    return value !== 0 || (1 / value == 1 / other);
+    return true;
   }
-  var valType = typeof value,
-      othType = typeof other;
-
-  // Exit early for unlike primitive values.
-  if ((valType != 'function' && valType != 'object' && othType != 'function' && othType != 'object') ||
-      value == null || other == null) {
-    // Return `false` unless both values are `NaN`.
+  if (value == null || other == null || (!isObject(value) && !isObjectLike(other))) {
     return value !== value && other !== other;
   }
   return baseIsEqualDeep(value, other, baseIsEqual, customizer, isLoose, stackA, stackB);

internal/baseIsEqualDeep.js

@@ -66,11 +66,11 @@ function baseIsEqualDeep(object, other, equalFunc, customizer, isLoose, stackA,
     return equalByTag(object, other, objTag);
   }
   if (!isLoose) {
-    var valWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
-        othWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');
+    var objIsWrapped = objIsObj && hasOwnProperty.call(object, '__wrapped__'),
+        othIsWrapped = othIsObj && hasOwnProperty.call(other, '__wrapped__');
 
-    if (valWrapped || othWrapped) {
-      return equalFunc(valWrapped ? object.value() : object, othWrapped ? other.value() : other, customizer, isLoose, stackA, stackB);
+    if (objIsWrapped || othIsWrapped) {
+      return equalFunc(objIsWrapped ? object.value() : object, othIsWrapped ? other.value() : other, customizer, isLoose, stackA, stackB);
     }
   }
   if (!isSameTag) {

internal/baseIsMatch.js

@@ -1,4 +1,5 @@
-var baseIsEqual = require('./baseIsEqual');
+var baseIsEqual = require('./baseIsEqual'),
+    toObject = require('./toObject');
 
 /**
  * The base implementation of `_.isMatch` without support for callback
@@ -6,41 +7,43 @@ var baseIsEqual = require('./baseIsEqual');
  *
  * @private
  * @param {Object} object The object to inspect.
- * @param {Array} props The source property names to match.
- * @param {Array} values The source values to match.
- * @param {Array} strictCompareFlags Strict comparison flags for source values.
+ * @param {Array} matchData The propery names, values, and compare flags to match.
  * @param {Function} [customizer] The function to customize comparing objects.
  * @returns {boolean} Returns `true` if `object` is a match, else `false`.
  */
-function baseIsMatch(object, props, values, strictCompareFlags, customizer) {
-  var index = -1,
-      length = props.length,
+function baseIsMatch(object, matchData, customizer) {
+  var index = matchData.length,
+      length = index,
       noCustomizer = !customizer;
 
-  while (++index < length) {
-    if ((noCustomizer && strictCompareFlags[index])
-          ? values[index] !== object[props[index]]
-          : !(props[index] in object)
+  if (object == null) {
+    return !length;
+  }
+  object = toObject(object);
+  while (index--) {
+    var data = matchData[index];
+    if ((noCustomizer && data[2])
+          ? data[1] !== object[data[0]]
+          : !(data[0] in object)
         ) {
       return false;
     }
   }
-  index = -1;
   while (++index < length) {
-    var key = props[index],
+    data = matchData[index];
+    var key = data[0],
         objValue = object[key],
-        srcValue = values[index];
+        srcValue = data[1];
 
-    if (noCustomizer && strictCompareFlags[index]) {
-      var result = objValue !== undefined || (key in object);
-    } else {
-      result = customizer ? customizer(objValue, srcValue, key) : undefined;
-      if (result === undefined) {
-        result = baseIsEqual(srcValue, objValue, customizer, true);
+    if (noCustomizer && data[2]) {
+      if (objValue === undefined && !(key in object)) {
+        return false;
+      }
+    } else {
+      var result = customizer ? customizer(objValue, srcValue, key) : undefined;
+      if (!(result === undefined ? baseIsEqual(srcValue, objValue, customizer, true) : result)) {
+        return false;
       }
-    }
-    if (!result) {
-      return false;
     }
   }
   return true;

internal/baseMap.js

@@ -1,6 +1,5 @@
 var baseEach = require('./baseEach'),
-    getLength = require('./getLength'),
-    isLength = require('./isLength');
+    isArrayLike = require('./isArrayLike');
 
 /**
  * The base implementation of `_.map` without support for callback shorthands
@@ -13,8 +12,7 @@ var baseEach = require('./baseEach'),
  */
 function baseMap(collection, iteratee) {
   var index = -1,
-      length = getLength(collection),
-      result = isLength(length) ? Array(length) : [];
+      result = isArrayLike(collection) ? Array(collection.length) : [];
 
   baseEach(collection, function(value, key, collection) {
     result[++index] = iteratee(value, key, collection);

internal/baseMatches.js

@@ -1,7 +1,5 @@
 var baseIsMatch = require('./baseIsMatch'),
-    constant = require('../utility/constant'),
-    isStrictComparable = require('./isStrictComparable'),
-    keys = require('../object/keys'),
+    getMatchData = require('./getMatchData'),
     toObject = require('./toObject');
 
 /**
@@ -12,35 +10,20 @@ var baseIsMatch = require('./baseIsMatch'),
  * @returns {Function} Returns the new function.
  */
 function baseMatches(source) {
-  var props = keys(source),
-      length = props.length;
+  var matchData = getMatchData(source);
+  if (matchData.length == 1 && matchData[0][2]) {
+    var key = matchData[0][0],
+        value = matchData[0][1];
 
-  if (!length) {
-    return constant(true);
-  }
-  if (length == 1) {
-    var key = props[0],
-        value = source[key];
-
-    if (isStrictComparable(value)) {
-      return function(object) {
-        if (object == null) {
-          return false;
-        }
-        return object[key] === value && (value !== undefined || (key in toObject(object)));
-      };
-    }
-  }
-  var values = Array(length),
-      strictCompareFlags = Array(length);
-
-  while (length--) {
-    value = source[props[length]];
-    values[length] = value;
-    strictCompareFlags[length] = isStrictComparable(value);
+    return function(object) {
+      if (object == null) {
+        return false;
+      }
+      return object[key] === value && (value !== undefined || (key in toObject(object)));
+    };
   }
   return function(object) {
-    return object != null && baseIsMatch(toObject(object), props, values, strictCompareFlags);
+    return baseIsMatch(object, matchData);
   };
 }
 

internal/baseMatchesProperty.js

@@ -9,17 +9,16 @@ var baseGet = require('./baseGet'),
     toPath = require('./toPath');
 
 /**
- * The base implementation of `_.matchesProperty` which does not which does
- * not clone `value`.
+ * The base implementation of `_.matchesProperty` which does not clone `srcValue`.
  *
  * @private
  * @param {string} path The path of the property to get.
- * @param {*} value The value to compare.
+ * @param {*} srcValue The value to compare.
  * @returns {Function} Returns the new function.
  */
-function baseMatchesProperty(path, value) {
+function baseMatchesProperty(path, srcValue) {
   var isArr = isArray(path),
-      isCommon = isKey(path) && isStrictComparable(value),
+      isCommon = isKey(path) && isStrictComparable(srcValue),
       pathKey = (path + '');
 
   path = toPath(path);
@@ -37,9 +36,9 @@ function baseMatchesProperty(path, value) {
       key = last(path);
       object = toObject(object);
     }
-    return object[key] === value
-      ? (value !== undefined || (key in object))
-      : baseIsEqual(value, object[key], null, true);
+    return object[key] === srcValue
+      ? (srcValue !== undefined || (key in object))
+      : baseIsEqual(srcValue, object[key], undefined, true);
   };
 }
 

internal/baseMerge.js

@@ -1,19 +1,12 @@
 var arrayEach = require('./arrayEach'),
     baseMergeDeep = require('./baseMergeDeep'),
-    getSymbols = require('./getSymbols'),
     isArray = require('../lang/isArray'),
-    isLength = require('./isLength'),
+    isArrayLike = require('./isArrayLike'),
     isObject = require('../lang/isObject'),
     isObjectLike = require('./isObjectLike'),
     isTypedArray = require('../lang/isTypedArray'),
     keys = require('../object/keys');
 
-/** Used for native method references. */
-var arrayProto = Array.prototype;
-
-/** Native method references. */
-var push = arrayProto.push;
-
 /**
  * The base implementation of `_.merge` without support for argument juggling,
  * multiple sources, and `this` binding `customizer` functions.
@@ -30,11 +23,9 @@ function baseMerge(object, source, customizer, stackA, stackB) {
   if (!isObject(object)) {
     return object;
   }
-  var isSrcArr = isLength(source.length) && (isArray(source) || isTypedArray(source));
-  if (!isSrcArr) {
-    var props = keys(source);
-    push.apply(props, getSymbols(source));
-  }
+  var isSrcArr = isArrayLike(source) && (isArray(source) || isTypedArray(source)),
+      props = isSrcArr ? null : keys(source);
+
   arrayEach(props || source, function(srcValue, key) {
     if (props) {
       key = srcValue;
@@ -53,7 +44,7 @@ function baseMerge(object, source, customizer, stackA, stackB) {
       if (isCommon) {
         result = srcValue;
       }
-      if ((isSrcArr || result !== undefined) &&
+      if ((result !== undefined || (isSrcArr && !(key in object))) &&
           (isCommon || (result === result ? (result !== value) : (value === value)))) {
         object[key] = result;
       }

internal/baseMergeDeep.js

@@ -1,8 +1,7 @@
 var arrayCopy = require('./arrayCopy'),
-    getLength = require('./getLength'),
     isArguments = require('../lang/isArguments'),
     isArray = require('../lang/isArray'),
-    isLength = require('./isLength'),
+    isArrayLike = require('./isArrayLike'),
     isPlainObject = require('../lang/isPlainObject'),
     isTypedArray = require('../lang/isTypedArray'),
     toPlainObject = require('../lang/toPlainObject');
@@ -38,10 +37,10 @@ function baseMergeDeep(object, source, key, mergeFunc, customizer, stackA, stack
 
   if (isCommon) {
     result = srcValue;
-    if (isLength(srcValue.length) && (isArray(srcValue) || isTypedArray(srcValue))) {
+    if (isArrayLike(srcValue) && (isArray(srcValue) || isTypedArray(srcValue))) {
       result = isArray(value)
         ? value
-        : (getLength(value) ? arrayCopy(value) : []);
+        : (isArrayLike(value) ? arrayCopy(value) : []);
     }
     else if (isPlainObject(srcValue) || isArguments(srcValue)) {
       result = isArguments(value)

internal/basePullAt.js

@@ -16,9 +16,9 @@ var splice = arrayProto.splice;
  * @returns {Array} Returns `array`.
  */
 function basePullAt(array, indexes) {
-  var length = indexes.length;
+  var length = array ? indexes.length : 0;
   while (length--) {
-    var index = parseFloat(indexes[length]);
+    var index = indexes[length];
     if (index != previous && isIndex(index)) {
       var previous = index;
       splice.call(array, index, 1);

internal/baseToString.js

@@ -1,5 +1,5 @@
 /**
- * Converts `value` to a string if it is not one. An empty string is returned
+ * Converts `value` to a string if it's not one. An empty string is returned
  * for `null` or `undefined` values.
  *
  * @private

internal/binaryIndex.js

@@ -2,7 +2,7 @@ var binaryIndexBy = require('./binaryIndexBy'),
     identity = require('../utility/identity');
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = Math.pow(2, 32) - 1,
+var MAX_ARRAY_LENGTH = 4294967295,
     HALF_MAX_ARRAY_LENGTH = MAX_ARRAY_LENGTH >>> 1;
 
 /**
@@ -25,7 +25,7 @@ function binaryIndex(array, value, retHighest) {
       var mid = (low + high) >>> 1,
           computed = array[mid];
 
-      if (retHighest ? (computed <= value) : (computed < value)) {
+      if ((retHighest ? (computed <= value) : (computed < value)) && computed !== null) {
         low = mid + 1;
       } else {
         high = mid;

internal/binaryIndexBy.js

@@ -5,8 +5,8 @@ var floor = Math.floor;
 var nativeMin = Math.min;
 
 /** Used as references for the maximum length and index of an array. */
-var MAX_ARRAY_LENGTH = Math.pow(2, 32) - 1,
-    MAX_ARRAY_INDEX =  MAX_ARRAY_LENGTH - 1;
+var MAX_ARRAY_LENGTH = 4294967295,
+    MAX_ARRAY_INDEX = MAX_ARRAY_LENGTH - 1;
 
 /**
  * This function is like `binaryIndex` except that it invokes `iteratee` for
@@ -27,17 +27,23 @@ function binaryIndexBy(array, value, iteratee, retHighest) {
   var low = 0,
       high = array ? array.length : 0,
       valIsNaN = value !== value,
+      valIsNull = value === null,
       valIsUndef = value === undefined;
 
   while (low < high) {
     var mid = floor((low + high) / 2),
         computed = iteratee(array[mid]),
+        isDef = computed !== undefined,
         isReflexive = computed === computed;
 
     if (valIsNaN) {
       var setLow = isReflexive || retHighest;
+    } else if (valIsNull) {
+      setLow = isReflexive && isDef && (retHighest || computed != null);
     } else if (valIsUndef) {
-      setLow = isReflexive && (retHighest || computed !== undefined);
+      setLow = isReflexive && (retHighest || isDef);
+    } else if (computed == null) {
+      setLow = false;
     } else {
       setLow = retHighest ? (computed <= value) : (computed < value);
     }

internal/bufferClone.js

@@ -1,11 +1,11 @@
 var constant = require('../utility/constant'),
-    isNative = require('../lang/isNative');
+    getNative = require('./getNative');
 
 /** Native method references. */
-var ArrayBuffer = isNative(ArrayBuffer = global.ArrayBuffer) && ArrayBuffer,
-    bufferSlice = isNative(bufferSlice = ArrayBuffer && new ArrayBuffer(0).slice) && bufferSlice,
+var ArrayBuffer = getNative(global, 'ArrayBuffer'),
+    bufferSlice = getNative(ArrayBuffer && new ArrayBuffer(0), 'slice'),
     floor = Math.floor,
-    Uint8Array = isNative(Uint8Array = global.Uint8Array) && Uint8Array;
+    Uint8Array = getNative(global, 'Uint8Array');
 
 /** Used to clone array buffers. */
 var Float64Array = (function() {
@@ -13,10 +13,10 @@ var Float64Array = (function() {
   // where the array buffer's `byteLength` is not a multiple of the typed
   // array's `BYTES_PER_ELEMENT`.
   try {
-    var func = isNative(func = global.Float64Array) && func,
+    var func = getNative(global, 'Float64Array'),
         result = new func(new ArrayBuffer(10), 0, 1) && func;
   } catch(e) {}
-  return result;
+  return result || null;
 }());
 
 /** Used as the size, in bytes, of each `Float64Array` element. */

internal/charAtCallback.js

@@ -1,12 +0,0 @@
-/**
- * Used by `_.max` and `_.min` as the default callback for string values.
- *
- * @private
- * @param {string} string The string to inspect.
- * @returns {number} Returns the code unit of the first character of the string.
- */
-function charAtCallback(string) {
-  return string.charCodeAt(0);
-}
-
-module.exports = charAtCallback;

internal/composeArgsRight.js

@@ -23,12 +23,12 @@ function composeArgsRight(args, partials, holders) {
   while (++argsIndex < argsLength) {
     result[argsIndex] = args[argsIndex];
   }
-  var pad = argsIndex;
+  var offset = argsIndex;
   while (++rightIndex < rightLength) {
-    result[pad + rightIndex] = partials[rightIndex];
+    result[offset + rightIndex] = partials[rightIndex];
   }
   while (++holdersIndex < holdersLength) {
-    result[pad + holders[holdersIndex]] = args[argsIndex++];
+    result[offset + holders[holdersIndex]] = args[argsIndex++];
   }
   return result;
 }

internal/createAssigner.js

@@ -16,19 +16,19 @@ function createAssigner(assigner) {
   return restParam(function(object, sources) {
     var index = -1,
         length = object == null ? 0 : sources.length,
-        customizer = length > 2 && sources[length - 2],
-        guard = length > 2 && sources[2],
-        thisArg = length > 1 && sources[length - 1];
+        customizer = length > 2 ? sources[length - 2] : undefined,
+        guard = length > 2 ? sources[2] : undefined,
+        thisArg = length > 1 ? sources[length - 1] : undefined;
 
     if (typeof customizer == 'function') {
       customizer = bindCallback(customizer, thisArg, 5);
       length -= 2;
     } else {
-      customizer = typeof thisArg == 'function' ? thisArg : null;
+      customizer = typeof thisArg == 'function' ? thisArg : undefined;
       length -= (customizer ? 1 : 0);
     }
     if (guard && isIterateeCall(sources[0], sources[1], guard)) {
-      customizer = length < 3 ? null : customizer;
+      customizer = length < 3 ? undefined : customizer;
       length = 1;
     }
     while (++index < length) {

internal/createCache.js

@@ -1,12 +1,12 @@
 var SetCache = require('./SetCache'),
     constant = require('../utility/constant'),
-    isNative = require('../lang/isNative');
+    getNative = require('./getNative');
 
 /** Native method references. */
-var Set = isNative(Set = global.Set) && Set;
+var Set = getNative(global, 'Set');
 
 /* Native method references for those with the same name as other `lodash` methods. */
-var nativeCreate = isNative(nativeCreate = Object.create) && nativeCreate;
+var nativeCreate = getNative(Object, 'create');
 
 /**
  * Creates a `Set` cache object to optimize linear searches of large arrays.

internal/createCtorWrapper.js

@@ -11,8 +11,20 @@ var baseCreate = require('./baseCreate'),
  */
 function createCtorWrapper(Ctor) {
   return function() {
+    // Use a `switch` statement to work with class constructors.
+    // See https://people.mozilla.org/~jorendorff/es6-draft.html#sec-ecmascript-function-objects-call-thisargument-argumentslist
+    // for more details.
+    var args = arguments;
+    switch (args.length) {
+      case 0: return new Ctor;
+      case 1: return new Ctor(args[0]);
+      case 2: return new Ctor(args[0], args[1]);
+      case 3: return new Ctor(args[0], args[1], args[2]);
+      case 4: return new Ctor(args[0], args[1], args[2], args[3]);
+      case 5: return new Ctor(args[0], args[1], args[2], args[3], args[4]);
+    }
     var thisBinding = baseCreate(Ctor.prototype),
-        result = Ctor.apply(thisBinding, arguments);
+        result = Ctor.apply(thisBinding, args);
 
     // Mimic the constructor's `return` behavior.
     // See https://es5.github.io/#x13.2.2 for more details.

internal/createExtremum.js

@@ -1,37 +1,31 @@
-var baseCallback = require('./baseCallback'),
-    charAtCallback = require('./charAtCallback'),
-    extremumBy = require('./extremumBy'),
-    isArray = require('../lang/isArray'),
+var arrayExtremum = require('./arrayExtremum'),
+    baseCallback = require('./baseCallback'),
+    baseExtremum = require('./baseExtremum'),
     isIterateeCall = require('./isIterateeCall'),
-    isString = require('../lang/isString'),
     toIterable = require('./toIterable');
 
 /**
  * Creates a `_.max` or `_.min` function.
  *
  * @private
- * @param {Function} arrayFunc The function to get the extremum value from an array.
- * @param {boolean} [isMin] Specify returning the minimum, instead of the maximum,
- *  extremum value.
+ * @param {Function} comparator The function used to compare values.
+ * @param {*} exValue The initial extremum value.
  * @returns {Function} Returns the new extremum function.
  */
-function createExtremum(arrayFunc, isMin) {
+function createExtremum(comparator, exValue) {
   return function(collection, iteratee, thisArg) {
     if (thisArg && isIterateeCall(collection, iteratee, thisArg)) {
       iteratee = null;
     }
-    var noIteratee = iteratee == null;
-
-    iteratee = noIteratee ? iteratee : baseCallback(iteratee, thisArg, 3);
-    if (noIteratee) {
-      var isArr = isArray(collection);
-      if (!isArr && isString(collection)) {
-        iteratee = charAtCallback;
-      } else {
-        return arrayFunc(isArr ? collection : toIterable(collection));
+    iteratee = baseCallback(iteratee, thisArg, 3);
+    if (iteratee.length == 1) {
+      collection = toIterable(collection);
+      var result = arrayExtremum(collection, iteratee, comparator, exValue);
+      if (!(collection.length && result === exValue)) {
+        return result;
       }
     }
-    return extremumBy(collection, iteratee, isMin);
+    return baseExtremum(collection, iteratee, comparator, exValue);
   };
 }
 

internal/createFind.js

@@ -19,7 +19,7 @@ function createFind(eachFunc, fromRight) {
       return index > -1 ? collection[index] : undefined;
     }
     return baseFind(collection, predicate, eachFunc);
-  }
+  };
 }
 
 module.exports = createFind;

internal/createFlow.js

@@ -4,6 +4,12 @@ var LodashWrapper = require('./LodashWrapper'),
     isArray = require('../lang/isArray'),
     isLaziable = require('./isLaziable');
 
+/** Used to compose bitmasks for wrapper metadata. */
+var CURRY_FLAG = 8,
+    PARTIAL_FLAG = 32,
+    ARY_FLAG = 128,
+    REARG_FLAG = 256;
+
 /** Used as the `TypeError` message for "Functions" methods. */
 var FUNC_ERROR_TEXT = 'Expected a function';
 
@@ -16,11 +22,8 @@ var FUNC_ERROR_TEXT = 'Expected a function';
  */
 function createFlow(fromRight) {
   return function() {
-    var length = arguments.length;
-    if (!length) {
-      return function() { return arguments[0]; };
-    }
     var wrapper,
+        length = arguments.length,
         index = fromRight ? length : -1,
         leftIndex = 0,
         funcs = Array(length);
@@ -30,16 +33,18 @@ function createFlow(fromRight) {
       if (typeof func != 'function') {
         throw new TypeError(FUNC_ERROR_TEXT);
       }
-      var funcName = wrapper ? '' : getFuncName(func);
-      wrapper = funcName == 'wrapper' ? new LodashWrapper([]) : wrapper;
+      if (!wrapper && LodashWrapper.prototype.thru && getFuncName(func) == 'wrapper') {
+        wrapper = new LodashWrapper([]);
+      }
     }
     index = wrapper ? -1 : length;
     while (++index < length) {
       func = funcs[index];
-      funcName = getFuncName(func);
 
-      var data = funcName == 'wrapper' ? getData(func) : null;
-      if (data && isLaziable(data[0])) {
+      var funcName = getFuncName(func),
+          data = funcName == 'wrapper' ? getData(func) : null;
+
+      if (data && isLaziable(data[0]) && data[1] == (ARY_FLAG | CURRY_FLAG | PARTIAL_FLAG | REARG_FLAG) && !data[4].length && data[9] == 1) {
         wrapper = wrapper[getFuncName(data[0])].apply(wrapper, data[3]);
       } else {
         wrapper = (func.length == 1 && isLaziable(func)) ? wrapper[funcName]() : wrapper.thru(func);
@@ -51,7 +56,7 @@ function createFlow(fromRight) {
         return wrapper.plant(args[0]).value();
       }
       var index = 0,
-          result = funcs[index].apply(this, args);
+          result = length ? funcs[index].apply(this, args) : args[0];
 
       while (++index < length) {
         result = funcs[index].call(this, result);

internal/createHybridWrapper.js

@@ -43,10 +43,8 @@ function createHybridWrapper(func, bitmask, thisArg, partials, holders, partials
       isBindKey = bitmask & BIND_KEY_FLAG,
       isCurry = bitmask & CURRY_FLAG,
       isCurryBound = bitmask & CURRY_BOUND_FLAG,
-      isCurryRight = bitmask & CURRY_RIGHT_FLAG;
-
-  var Ctor = !isBindKey && createCtorWrapper(func),
-      key = func;
+      isCurryRight = bitmask & CURRY_RIGHT_FLAG,
+      Ctor = isBindKey ? null : createCtorWrapper(func);
 
   function wrapper() {
     // Avoid `arguments` object use disqualifying optimizations by
@@ -93,17 +91,18 @@ function createHybridWrapper(func, bitmask, thisArg, partials, holders, partials
         return result;
       }
     }
-    var thisBinding = isBind ? thisArg : this;
-    if (isBindKey) {
-      func = thisBinding[key];
-    }
+    var thisBinding = isBind ? thisArg : this,
+        fn = isBindKey ? thisBinding[func] : func;
+
     if (argPos) {
       args = reorder(args, argPos);
     }
     if (isAry && ary < args.length) {
       args.length = ary;
     }
-    var fn = (this && this !== global && this instanceof wrapper) ? (Ctor || createCtorWrapper(func)) : func;
+    if (this && this !== global && this instanceof wrapper) {
+      fn = Ctor || createCtorWrapper(func);
+    }
     return fn.apply(thisBinding, args);
   }
   return wrapper;

internal/createObjectMapper.js

@@ -0,0 +1,26 @@
+var baseCallback = require('./baseCallback'),
+    baseForOwn = require('./baseForOwn');
+
+/**
+ * Creates a function for `_.mapKeys` or `_.mapValues`.
+ *
+ * @private
+ * @param {boolean} [isMapKeys] Specify mapping keys instead of values.
+ * @returns {Function} Returns the new map function.
+ */
+function createObjectMapper(isMapKeys) {
+  return function(object, iteratee, thisArg) {
+    var result = {};
+    iteratee = baseCallback(iteratee, thisArg, 3);
+
+    baseForOwn(object, function(value, key, object) {
+      var mapped = iteratee(value, key, object);
+      key = isMapKeys ? mapped : key;
+      value = isMapKeys ? value : mapped;
+      result[key] = value;
+    });
+    return result;
+  };
+}
+
+module.exports = createObjectMapper;

internal/createPadDir.js

@@ -11,7 +11,7 @@ var baseToString = require('./baseToString'),
 function createPadDir(fromRight) {
   return function(string, length, chars) {
     string = baseToString(string);
-    return string && ((fromRight ? string : '') + createPadding(string, length, chars) + (fromRight ? '' : string));
+    return (fromRight ? string : '') + createPadding(string, length, chars) + (fromRight ? '' : string);
   };
 }
 

internal/equalArrays.js

@@ -1,3 +1,5 @@
+var arraySome = require('./arraySome');
+
 /**
  * A specialized version of `baseIsEqualDeep` for arrays with support for
  * partial deep comparisons.
@@ -15,40 +17,35 @@
 function equalArrays(array, other, equalFunc, customizer, isLoose, stackA, stackB) {
   var index = -1,
       arrLength = array.length,
-      othLength = other.length,
-      result = true;
+      othLength = other.length;
 
   if (arrLength != othLength && !(isLoose && othLength > arrLength)) {
     return false;
   }
-  // Deep compare the contents, ignoring non-numeric properties.
-  while (result && ++index < arrLength) {
+  // Ignore non-index properties.
+  while (++index < arrLength) {
     var arrValue = array[index],
-        othValue = other[index];
+        othValue = other[index],
+        result = customizer ? customizer(isLoose ? othValue : arrValue, isLoose ? arrValue : othValue, index) : undefined;
 
-    result = undefined;
-    if (customizer) {
-      result = isLoose
-        ? customizer(othValue, arrValue, index)
-        : customizer(arrValue, othValue, index);
-    }
-    if (result === undefined) {
-      // Recursively compare arrays (susceptible to call stack limits).
-      if (isLoose) {
-        var othIndex = othLength;
-        while (othIndex--) {
-          othValue = other[othIndex];
-          result = (arrValue && arrValue === othValue) || equalFunc(arrValue, othValue, customizer, isLoose, stackA, stackB);
-          if (result) {
-            break;
-          }
-        }
-      } else {
-        result = (arrValue && arrValue === othValue) || equalFunc(arrValue, othValue, customizer, isLoose, stackA, stackB);
+    if (result !== undefined) {
+      if (result) {
+        continue;
       }
+      return false;
+    }
+    // Recursively compare arrays (susceptible to call stack limits).
+    if (isLoose) {
+      if (!arraySome(other, function(othValue) {
+            return arrValue === othValue || equalFunc(arrValue, othValue, customizer, isLoose, stackA, stackB);
+          })) {
+        return false;
+      }
+    } else if (!(arrValue === othValue || equalFunc(arrValue, othValue, customizer, isLoose, stackA, stackB))) {
+      return false;
     }
   }
-  return !!result;
+  return true;
 }
 
 module.exports = equalArrays;

internal/equalByTag.js

@@ -34,8 +34,7 @@ function equalByTag(object, other, tag) {
       // Treat `NaN` vs. `NaN` as equal.
       return (object != +object)
         ? other != +other
-        // But, treat `-0` vs. `+0` as not equal.
-        : (object == 0 ? ((1 / object) == (1 / other)) : object == +other);
+        : object == +other;
 
     case regexpTag:
     case stringTag:

internal/equalObjects.js

@@ -29,29 +29,22 @@ function equalObjects(object, other, equalFunc, customizer, isLoose, stackA, sta
   if (objLength != othLength && !isLoose) {
     return false;
   }
-  var skipCtor = isLoose,
-      index = -1;
-
-  while (++index < objLength) {
-    var key = objProps[index],
-        result = isLoose ? key in other : hasOwnProperty.call(other, key);
-
-    if (result) {
-      var objValue = object[key],
-          othValue = other[key];
-
-      result = undefined;
-      if (customizer) {
-        result = isLoose
-          ? customizer(othValue, objValue, key)
-          : customizer(objValue, othValue, key);
-      }
-      if (result === undefined) {
-        // Recursively compare objects (susceptible to call stack limits).
-        result = (objValue && objValue === othValue) || equalFunc(objValue, othValue, customizer, isLoose, stackA, stackB);
-      }
+  var index = objLength;
+  while (index--) {
+    var key = objProps[index];
+    if (!(isLoose ? key in other : hasOwnProperty.call(other, key))) {
+      return false;
     }
-    if (!result) {
+  }
+  var skipCtor = isLoose;
+  while (++index < objLength) {
+    key = objProps[index];
+    var objValue = object[key],
+        othValue = other[key],
+        result = customizer ? customizer(isLoose ? othValue : objValue, isLoose? objValue : othValue, key) : undefined;
+
+    // Recursively compare objects (susceptible to call stack limits).
+    if (!(result === undefined ? equalFunc(objValue, othValue, customizer, isLoose, stackA, stackB) : result)) {
       return false;
     }
     skipCtor || (skipCtor = key == 'constructor');

internal/getFuncName.js

@@ -1,7 +1,4 @@
-var baseProperty = require('./baseProperty'),
-    constant = require('../utility/constant'),
-    realNames = require('./realNames'),
-    support = require('../support');
+var realNames = require('./realNames');
 
 /**
  * Gets the name of `func`.
@@ -10,28 +7,19 @@ var baseProperty = require('./baseProperty'),
  * @param {Function} func The function to query.
  * @returns {string} Returns the function name.
  */
-var getFuncName = (function() {
-  if (!support.funcNames) {
-    return constant('');
-  }
-  if (constant.name == 'constant') {
-    return baseProperty('name');
-  }
-  return function(func) {
-    var result = func.name,
-        array = realNames[result],
-        length = array ? array.length : 0;
+function getFuncName(func) {
+  var result = func.name,
+      array = realNames[result],
+      length = array ? array.length : 0;
 
-    while (length--) {
-      var data = array[length],
-          otherFunc = data.func;
-
-      if (otherFunc == null || otherFunc == func) {
-        return data.name;
-      }
+  while (length--) {
+    var data = array[length],
+        otherFunc = data.func;
+    if (otherFunc == null || otherFunc == func) {
+      return data.name;
     }
-    return result;
-  };
-}());
+  }
+  return result;
+}
 
 module.exports = getFuncName;

internal/getLength.js

@@ -4,7 +4,7 @@ var baseProperty = require('./baseProperty');
  * Gets the "length" property value of `object`.
  *
  * **Note:** This function is used to avoid a [JIT bug](https://bugs.webkit.org/show_bug.cgi?id=142792)
- * in Safari on iOS 8.1 ARM64.
+ * that affects Safari on at least iOS 8.1-8.3 ARM64.
  *
  * @private
  * @param {Object} object The object to query.

internal/getMatchData.js

@@ -0,0 +1,21 @@
+var isStrictComparable = require('./isStrictComparable'),
+    pairs = require('../object/pairs');
+
+/**
+ * Gets the propery names, values, and compare flags of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @returns {Array} Returns the match data of `object`.
+ */
+function getMatchData(object) {
+  var result = pairs(object),
+      length = result.length;
+
+  while (length--) {
+    result[length][2] = isStrictComparable(result[length][1]);
+  }
+  return result;
+}
+
+module.exports = getMatchData;

internal/getNative.js

@@ -0,0 +1,16 @@
+var isNative = require('../lang/isNative');
+
+/**
+ * Gets the native function at `key` of `object`.
+ *
+ * @private
+ * @param {Object} object The object to query.
+ * @param {string} key The key of the method to get.
+ * @returns {*} Returns the function if it's native, else `undefined`.
+ */
+function getNative(object, key) {
+  var value = object == null ? undefined : object[key];
+  return isNative(value) ? value : undefined;
+}
+
+module.exports = getNative;

internal/getSymbols.js

@@ -1,19 +0,0 @@
-var constant = require('../utility/constant'),
-    isNative = require('../lang/isNative'),
-    toObject = require('./toObject');
-
-/** Native method references. */
-var getOwnPropertySymbols = isNative(getOwnPropertySymbols = Object.getOwnPropertySymbols) && getOwnPropertySymbols;
-
-/**
- * Creates an array of the own symbols of `object`.
- *
- * @private
- * @param {Object} object The object to query.
- * @returns {Array} Returns the array of symbols.
- */
-var getSymbols = !getOwnPropertySymbols ? constant([]) : function(object) {
-  return getOwnPropertySymbols(toObject(object));
-};
-
-module.exports = getSymbols;

internal/isArrayLike.js

@@ -0,0 +1,15 @@
+var getLength = require('./getLength'),
+    isLength = require('./isLength');
+
+/**
+ * Checks if `value` is array-like.
+ *
+ * @private
+ * @param {*} value The value to check.
+ * @returns {boolean} Returns `true` if `value` is array-like, else `false`.
+ */
+function isArrayLike(value) {
+  return value != null && isLength(getLength(value));
+}
+
+module.exports = isArrayLike;

internal/isIndex.js

@@ -1,8 +1,11 @@
+/** Used to detect unsigned integer values. */
+var reIsUint = /^\d+$/;
+
 /**
  * Used as the [maximum length](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.max_safe_integer)
  * of an array-like value.
  */
-var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;
+var MAX_SAFE_INTEGER = 9007199254740991;
 
 /**
  * Checks if `value` is a valid array-like index.
@@ -13,7 +16,7 @@ var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;
  * @returns {boolean} Returns `true` if `value` is a valid index, else `false`.
  */
 function isIndex(value, length) {
-  value = +value;
+  value = (typeof value == 'number' || reIsUint.test(value)) ? +value : -1;
   length = length == null ? MAX_SAFE_INTEGER : length;
   return value > -1 && value % 1 == 0 && value < length;
 }

internal/isIterateeCall.js

@@ -1,6 +1,5 @@
-var getLength = require('./getLength'),
+var isArrayLike = require('./isArrayLike'),
     isIndex = require('./isIndex'),
-    isLength = require('./isLength'),
     isObject = require('../lang/isObject');
 
 /**
@@ -17,13 +16,9 @@ function isIterateeCall(value, index, object) {
     return false;
   }
   var type = typeof index;
-  if (type == 'number') {
-    var length = getLength(object),
-        prereq = isLength(length) && isIndex(index, length);
-  } else {
-    prereq = type == 'string' && index in object;
-  }
-  if (prereq) {
+  if (type == 'number'
+      ? (isArrayLike(object) && isIndex(index, object.length))
+      : (type == 'string' && index in object)) {
     var other = object[index];
     return value === value ? (value === other) : (other !== other);
   }

internal/isKey.js

@@ -2,7 +2,7 @@ var isArray = require('../lang/isArray'),
     toObject = require('./toObject');
 
 /** Used to match property names within property paths. */
-var reIsDeepProp = /\.|\[(?:[^[\]]+|(["'])(?:(?!\1)[^\n\\]|\\.)*?)\1\]/,
+var reIsDeepProp = /\.|\[(?:[^[\]]*|(["'])(?:(?!\1)[^\n\\]|\\.)*?\1)\]/,
     reIsPlainProp = /^\w*$/;
 
 /**

internal/isLaziable.js

@@ -1,4 +1,5 @@
 var LazyWrapper = require('./LazyWrapper'),
+    getData = require('./getData'),
     getFuncName = require('./getFuncName'),
     lodash = require('../chain/lodash');
 
@@ -11,7 +12,15 @@ var LazyWrapper = require('./LazyWrapper'),
  */
 function isLaziable(func) {
   var funcName = getFuncName(func);
-  return !!funcName && func === lodash[funcName] && funcName in LazyWrapper.prototype;
+  if (!(funcName in LazyWrapper.prototype)) {
+    return false;
+  }
+  var other = lodash[funcName];
+  if (func === other) {
+    return true;
+  }
+  var data = getData(other);
+  return !!data && func === data[0];
 }
 
 module.exports = isLaziable;

internal/isLength.js

@@ -2,7 +2,7 @@
  * Used as the [maximum length](https://people.mozilla.org/~jorendorff/es6-draft.html#sec-number.max_safe_integer)
  * of an array-like value.
  */
-var MAX_SAFE_INTEGER = Math.pow(2, 53) - 1;
+var MAX_SAFE_INTEGER = 9007199254740991;
 
 /**
  * Checks if `value` is a valid array-like length.

internal/isStrictComparable.js

@@ -9,7 +9,7 @@ var isObject = require('../lang/isObject');
  *  equality comparisons, else `false`.
  */
 function isStrictComparable(value) {
-  return value === value && (value === 0 ? ((1 / value) > 0) : !isObject(value));
+  return value === value && !isObject(value);
 }
 
 module.exports = isStrictComparable;

internal/metaMap.js

@@ -1,7 +1,7 @@
-var isNative = require('../lang/isNative');
+var getNative = require('./getNative');
 
 /** Native method references. */
-var WeakMap = isNative(WeakMap = global.WeakMap) && WeakMap;
+var WeakMap = getNative(global, 'WeakMap');
 
 /** Used to store function metadata. */
 var metaMap = WeakMap && new WeakMap;

internal/pickByArray.js

@@ -1,7 +1,7 @@
 var toObject = require('./toObject');
 
 /**
- * A specialized version of `_.pick` that picks `object` properties specified
+ * A specialized version of `_.pick` which picks `object` properties specified
  * by `props`.
  *
  * @private

internal/pickByCallback.js

@@ -1,7 +1,7 @@
 var baseForIn = require('./baseForIn');
 
 /**
- * A specialized version of `_.pick` that picks `object` properties `predicate`
+ * A specialized version of `_.pick` which picks `object` properties `predicate`
  * returns truthy for.
  *
  * @private

internal/shimKeys.js

@@ -2,8 +2,7 @@ var isArguments = require('../lang/isArguments'),
     isArray = require('../lang/isArray'),
     isIndex = require('./isIndex'),
     isLength = require('./isLength'),
-    keysIn = require('../object/keysIn'),
-    support = require('../support');
+    keysIn = require('../object/keysIn');
 
 /** Used for native method references. */
 var objectProto = Object.prototype;
@@ -24,8 +23,8 @@ function shimKeys(object) {
       propsLength = props.length,
       length = propsLength && object.length;
 
-  var allowIndexes = length && isLength(length) &&
-    (isArray(object) || (support.nonEnumArgs && isArguments(object)));
+  var allowIndexes = !!length && isLength(length) &&
+    (isArray(object) || isArguments(object));
 
   var index = -1,
       result = [];

internal/toIterable.js

@@ -1,10 +1,9 @@
-var getLength = require('./getLength'),
-    isLength = require('./isLength'),
+var isArrayLike = require('./isArrayLike'),
     isObject = require('../lang/isObject'),
     values = require('../object/values');
 
 /**
- * Converts `value` to an array-like object if it is not one.
+ * Converts `value` to an array-like object if it's not one.
  *
  * @private
  * @param {*} value The value to process.
@@ -14,7 +13,7 @@ function toIterable(value) {
   if (value == null) {
     return [];
   }
-  if (!isLength(getLength(value))) {
+  if (!isArrayLike(value)) {
     return values(value);
   }
   return isObject(value) ? value : Object(value);

internal/toObject.js

@@ -1,7 +1,7 @@
 var isObject = require('../lang/isObject');
 
 /**
- * Converts `value` to an object if it is not one.
+ * Converts `value` to an object if it's not one.
  *
  * @private
  * @param {*} value The value to process.

internal/toPath.js

@@ -8,7 +8,7 @@ var rePropName = /[^.[\]]+|\[(?:(-?\d+(?:\.\d+)?)|(["'])((?:(?!\2)[^\n\\]|\\.)*?
 var reEscapeChar = /\\(\\)?/g;
 
 /**
- * Converts `value` to property path array if it is not one.
+ * Converts `value` to property path array if it's not one.
  *
  * @private
  * @param {*} value The value to process.

lang.js

@@ -1,6 +1,9 @@
 module.exports = {
   'clone': require('./lang/clone'),
   'cloneDeep': require('./lang/cloneDeep'),
+  'eq': require('./lang/eq'),
+  'gt': require('./lang/gt'),
+  'gte': require('./lang/gte'),
   'isArguments': require('./lang/isArguments'),
   'isArray': require('./lang/isArray'),
   'isBoolean': require('./lang/isBoolean'),
@@ -22,6 +25,8 @@ module.exports = {
   'isString': require('./lang/isString'),
   'isTypedArray': require('./lang/isTypedArray'),
   'isUndefined': require('./lang/isUndefined'),
+  'lt': require('./lang/lt'),
+  'lte': require('./lang/lte'),
   'toArray': require('./lang/toArray'),
   'toPlainObject': require('./lang/toPlainObject')
 };

lang/clone.js

@@ -62,8 +62,9 @@ function clone(value, isDeep, customizer, thisArg) {
     customizer = isDeep;
     isDeep = false;
   }
-  customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 1);
-  return baseClone(value, isDeep, customizer);
+  return typeof customizer == 'function'
+    ? baseClone(value, isDeep, bindCallback(customizer, thisArg, 1))
+    : baseClone(value, isDeep);
 }
 
 module.exports = clone;

lang/cloneDeep.js

@@ -47,8 +47,9 @@ var baseClone = require('../internal/baseClone'),
  * // => 20
  */
 function cloneDeep(value, customizer, thisArg) {
-  customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 1);
-  return baseClone(value, true, customizer);
+  return typeof customizer == 'function'
+    ? baseClone(value, true, bindCallback(customizer, thisArg, 1))
+    : baseClone(value, true);
 }
 
 module.exports = cloneDeep;

lang/eq.js

@@ -0,0 +1 @@
+module.exports = require('./isEqual');

lang/gt.js

@@ -0,0 +1,25 @@
+/**
+ * Checks if `value` is greater than `other`.
+ *
+ * @static
+ * @memberOf _
+ * @category Lang
+ * @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`.
+ * @example
+ *
+ * _.gt(3, 1);
+ * // => true
+ *
+ * _.gt(3, 3);
+ * // => false
+ *
+ * _.gt(1, 3);
+ * // => false
+ */
+function gt(value, other) {
+  return value > other;
+}
+
+module.exports = gt;

lang/gte.js

@@ -0,0 +1,25 @@
+/**
+ * Checks if `value` is greater than or equal to `other`.
+ *
+ * @static
+ * @memberOf _
+ * @category Lang
+ * @param {*} value The value to compare.
+ * @param {*} other The other value to compare.
+ * @returns {boolean} Returns `true` if `value` is greater than or equal to `other`, else `false`.
+ * @example
+ *
+ * _.gte(3, 1);
+ * // => true
+ *
+ * _.gte(3, 3);
+ * // => true
+ *
+ * _.gte(1, 3);
+ * // => false
+ */
+function gte(value, other) {
+  return value >= other;
+}
+
+module.exports = gte;

lang/isArguments.js

@@ -1,4 +1,4 @@
-var isLength = require('../internal/isLength'),
+var isArrayLike = require('../internal/isArrayLike'),
     isObjectLike = require('../internal/isObjectLike');
 
 /** `Object#toString` result references. */
@@ -30,8 +30,7 @@ var objToString = objectProto.toString;
  * // => false
  */
 function isArguments(value) {
-  var length = isObjectLike(value) ? value.length : undefined;
-  return isLength(length) && objToString.call(value) == argsTag;
+  return isObjectLike(value) && isArrayLike(value) && objToString.call(value) == argsTag;
 }
 
 module.exports = isArguments;

lang/isArray.js

@@ -1,5 +1,5 @@
-var isLength = require('../internal/isLength'),
-    isNative = require('./isNative'),
+var getNative = require('../internal/getNative'),
+    isLength = require('../internal/isLength'),
     isObjectLike = require('../internal/isObjectLike');
 
 /** `Object#toString` result references. */
@@ -15,7 +15,7 @@ var objectProto = Object.prototype;
 var objToString = objectProto.toString;
 
 /* Native method references for those with the same name as other `lodash` methods. */
-var nativeIsArray = isNative(nativeIsArray = Array.isArray) && nativeIsArray;
+var nativeIsArray = getNative(Array, 'isArray');
 
 /**
  * Checks if `value` is classified as an `Array` object.

lang/isEmpty.js

@@ -1,8 +1,7 @@
-var getLength = require('../internal/getLength'),
-    isArguments = require('./isArguments'),
+var isArguments = require('./isArguments'),
     isArray = require('./isArray'),
+    isArrayLike = require('../internal/isArrayLike'),
     isFunction = require('./isFunction'),
-    isLength = require('../internal/isLength'),
     isObjectLike = require('../internal/isObjectLike'),
     isString = require('./isString'),
     keys = require('../object/keys');
@@ -38,10 +37,9 @@ function isEmpty(value) {
   if (value == null) {
     return true;
   }
-  var length = getLength(value);
-  if (isLength(length) && (isArray(value) || isString(value) || isArguments(value) ||
+  if (isArrayLike(value) && (isArray(value) || isString(value) || isArguments(value) ||
       (isObjectLike(value) && isFunction(value.splice)))) {
-    return !length;
+    return !value.length;
   }
   return !keys(value).length;
 }

lang/isEqual.js

@@ -1,6 +1,5 @@
 var baseIsEqual = require('../internal/baseIsEqual'),
-    bindCallback = require('../internal/bindCallback'),
-    isStrictComparable = require('../internal/isStrictComparable');
+    bindCallback = require('../internal/bindCallback');
 
 /**
  * Performs a deep comparison between two values to determine if they are
@@ -17,6 +16,7 @@ var baseIsEqual = require('../internal/baseIsEqual'),
  *
  * @static
  * @memberOf _
+ * @alias eq
  * @category Lang
  * @param {*} value The value to compare.
  * @param {*} other The other value to compare.
@@ -46,12 +46,9 @@ var baseIsEqual = require('../internal/baseIsEqual'),
  * // => true
  */
 function isEqual(value, other, customizer, thisArg) {
-  customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 3);
-  if (!customizer && isStrictComparable(value) && isStrictComparable(other)) {
-    return value === other;
-  }
+  customizer = typeof customizer == 'function' ? bindCallback(customizer, thisArg, 3) : undefined;
   var result = customizer ? customizer(value, other) : undefined;
-  return result === undefined ? baseIsEqual(value, other, customizer) : !!result;
+  return  result === undefined ? baseIsEqual(value, other, customizer) : !!result;
 }
 
 module.exports = isEqual;

lang/isFinite.js

@@ -1,8 +1,8 @@
-var isNative = require('./isNative');
+var getNative = require('../internal/getNative');
 
 /* Native method references for those with the same name as other `lodash` methods. */
 var nativeIsFinite = global.isFinite,
-    nativeNumIsFinite = isNative(nativeNumIsFinite = Number.isFinite) && nativeNumIsFinite;
+    nativeNumIsFinite = getNative(Number, 'isFinite');
 
 /**
  * Checks if `value` is a finite primitive number.

lang/isFunction.js

@@ -1,5 +1,5 @@
 var baseIsFunction = require('../internal/baseIsFunction'),
-    isNative = require('./isNative');
+    getNative = require('../internal/getNative');
 
 /** `Object#toString` result references. */
 var funcTag = '[object Function]';
@@ -14,7 +14,7 @@ var objectProto = Object.prototype;
 var objToString = objectProto.toString;
 
 /** Native method references. */
-var Uint8Array = isNative(Uint8Array = global.Uint8Array) && Uint8Array;
+var Uint8Array = getNative(global, 'Uint8Array');
 
 /**
  * Checks if `value` is classified as a `Function` object.

lang/isMatch.js

@@ -1,8 +1,6 @@
 var baseIsMatch = require('../internal/baseIsMatch'),
     bindCallback = require('../internal/bindCallback'),
-    isStrictComparable = require('../internal/isStrictComparable'),
-    keys = require('../object/keys'),
-    toObject = require('../internal/toObject');
+    getMatchData = require('../internal/getMatchData');
 
 /**
  * Performs a deep comparison between `object` and `source` to determine if
@@ -44,33 +42,8 @@ var baseIsMatch = require('../internal/baseIsMatch'),
  * // => true
  */
 function isMatch(object, source, customizer, thisArg) {
-  var props = keys(source),
-      length = props.length;
-
-  if (!length) {
-    return true;
-  }
-  if (object == null) {
-    return false;
-  }
-  customizer = typeof customizer == 'function' && bindCallback(customizer, thisArg, 3);
-  object = toObject(object);
-  if (!customizer && length == 1) {
-    var key = props[0],
-        value = source[key];
-
-    if (isStrictComparable(value)) {
-      return value === object[key] && (value !== undefined || (key in object));
-    }
-  }
-  var values = Array(length),
-      strictCompareFlags = Array(length);
-
-  while (length--) {
-    value = values[length] = source[props[length]];
-    strictCompareFlags[length] = isStrictComparable(value);
-  }
-  return baseIsMatch(object, props, values, strictCompareFlags, customizer);
+  customizer = typeof customizer == 'function' ? bindCallback(customizer, thisArg, 3) : undefined;
+  return baseIsMatch(object, getMatchData(source), customizer);
 }
 
 module.exports = isMatch;