Add _.create.

lodash.js

@@ -1279,7 +1279,7 @@
         // non `Object` object instances with different constructors are not equal
         if (ctorA != ctorB &&
               !(isFunction(ctorA) && ctorA instanceof ctorA && isFunction(ctorB) && ctorB instanceof ctorB) &&
-              (!nativeCreate || ('constructor' in a && 'constructor' in b))
+              ('constructor' in a && 'constructor' in b)
             ) {
           return false;
         }
@@ -1619,7 +1619,7 @@
           }
           if (this instanceof bound) {
             // ensure `new bound` is an instance of `func`
-            thisBinding = createObject(func.prototype);
+            thisBinding = create(func.prototype);
 
             // mimic the constructor's `return` behavior
             // http://es5.github.io/#x13.2.2
@@ -1682,28 +1682,6 @@
       );
     }
 
-    /**
-     * Creates a new object with the specified `prototype`.
-     *
-     * @private
-     * @param {Object} prototype The prototype object.
-     * @returns {Object} Returns the new object.
-     */
-    function createObject(prototype) {
-      return isObject(prototype) ? nativeCreate(prototype) : {};
-    }
-    // fallback for browsers without `Object.create`
-    if (!nativeCreate) {
-      createObject = function(prototype) {
-        if (isObject(prototype)) {
-          noop.prototype = prototype;
-          var result = new noop;
-          noop.prototype = null;
-        }
-        return result || {};
-      };
-    }
-
     /**
      * Used by `escape` to convert characters to HTML entities.
      *
@@ -2093,6 +2071,50 @@
       return baseClone(value, true, typeof callback == 'function' && baseCreateCallback(callback, thisArg, 1));
     }
 
+    /**
+     * Creates a new object with the specified `prototype`.
+     *
+     * @static
+     * @memberOf _
+     * @category Objects
+     * @param {Object} prototype The prototype object.
+     * @returns {Object} Returns the new object.
+     * @example
+     *
+     * function Shape() {
+     *   this.x = 0;
+     *   this.y = 0;
+     * }
+     *
+     * function Circle() {
+     *   Shape.call(this);
+     * }
+     *
+     * Circle.prototype = _.create(Shape.prototype);
+     * Circle.prototype.constructor = Circle;
+     *
+     * var circle = new Circle;
+     * circle instanceof Circle
+     * // => true
+     *
+     * circle instanceof Shape
+     * // => true
+     */
+    function create(prototype) {
+      return isObject(prototype) ? nativeCreate(prototype) : {};
+    }
+    // fallback for browsers without `Object.create`
+    if (!nativeCreate) {
+      create = function(prototype) {
+        if (isObject(prototype)) {
+          noop.prototype = prototype;
+          var result = new noop;
+          noop.prototype = null;
+        }
+        return result || {};
+      };
+    }
+
     /**
      * Assigns own enumerable properties of source object(s) to the destination
      * object for all destination properties that resolve to `undefined`. Once a
@@ -2237,18 +2259,20 @@
      * @returns {Object} Returns `object`.
      * @example
      *
-     * function Dog(name) {
-     *   this.name = name;
+     * function Shape() {
+     *   this.x = 0;
+     *   this.y = 0;
      * }
      *
-     * Dog.prototype.bark = function() {
-     *   console.log('Woof, woof!');
+     * Shape.prototype.move = function(x, y) {
+     *   this.x += x;
+     *   this.y += y;
      * };
      *
-     * _.forIn(new Dog('Dagny'), function(value, key) {
+     * _.forIn(new Shape, function(value, key) {
      *   console.log(key);
      * });
-     * // => logs 'bark' and 'name' (property order is not guaranteed across environments)
+     * // => logs 'x', 'y', and 'move' (property order is not guaranteed across environments)
      */
     var forIn = createIterator(eachIteratorOptions, forOwnIteratorOptions, {
       'useHas': false
@@ -2267,18 +2291,20 @@
      * @returns {Object} Returns `object`.
      * @example
      *
-     * function Dog(name) {
-     *   this.name = name;
+     * function Shape() {
+     *   this.x = 0;
+     *   this.y = 0;
      * }
      *
-     * Dog.prototype.bark = function() {
-     *   console.log('Woof, woof!');
+     * Shape.prototype.move = function(x, y) {
+     *   this.x += x;
+     *   this.y += y;
      * };
      *
-     * _.forInRight(new Dog('Dagny'), function(value, key) {
+     * _.forInRight(new Shape, function(value, key) {
      *   console.log(key);
      * });
-     * // => logs 'name' and 'bark' assuming `_.forIn ` logs 'bark' and 'name'
+     * // => logs 'move', 'y', and 'x' assuming `_.forIn ` logs 'x', 'y', and 'move'
      */
     function forInRight(object, callback, thisArg) {
       var pairs = [];
@@ -2720,18 +2746,18 @@
      * @returns {boolean} Returns `true` if `value` is a plain object, else `false`.
      * @example
      *
-     * function Person(name, age) {
-     *   this.name = name;
-     *   this.age = age;
+     * function Shape() {
+     *   this.x = 0;
+     *   this.y = 0;
      * }
      *
-     * _.isPlainObject(new Person('fred', 40));
+     * _.isPlainObject(new Shape);
      * // => false
      *
      * _.isPlainObject([1, 2, 3]);
      * // => false
      *
-     * _.isPlainObject({ 'name': 'fred', 'age': 40 });
+     * _.isPlainObject({ 'x': 0, 'y': 0 });
      * // => true
      */
     var isPlainObject = !getPrototypeOf ? shimIsPlainObject : function(value) {
@@ -3015,7 +3041,7 @@
      * @static
      * @memberOf _
      * @category Objects
-     * @param {Array|Object} collection The collection to iterate over.
+     * @param {Array|Object} object The object to iterate over.
      * @param {Function} [callback=identity] The function called per iteration.
      * @param {*} [accumulator] The custom accumulator value.
      * @param {*} [thisArg] The `this` binding of `callback`.
@@ -3037,8 +3063,6 @@
      */
     function transform(object, callback, accumulator, thisArg) {
       var isArr = isArray(object);
-      callback = baseCreateCallback(callback, thisArg, 4);
-
       if (accumulator == null) {
         if (isArr) {
           accumulator = [];
@@ -3046,12 +3070,15 @@
           var ctor = object && object.constructor,
               proto = ctor && ctor.prototype;
 
-          accumulator = createObject(proto);
+          accumulator = create(proto);
         }
       }
-      (isArr ? baseEach : forOwn)(object, function(value, index, object) {
-        return callback(accumulator, value, index, object);
-      });
+      if (callback) {
+        callback = baseCreateCallback(callback, thisArg, 4);
+        (isArr ? baseEach : forOwn)(object, function(value, index, object) {
+          return callback(accumulator, value, index, object);
+        });
+      }
       return accumulator;
     }
 
@@ -6545,6 +6572,7 @@
     lodash.compact = compact;
     lodash.compose = compose;
     lodash.countBy = countBy;
+    lodash.create = create;
     lodash.createCallback = createCallback;
     lodash.curry = curry;
     lodash.debounce = debounce;