Make _.extend and alias of _.assign and make _.assign iterate only own enumerable source props to align with ES6.

Former-commit-id: 37ba7c3066c1ea70210346a9bf598e8587e907db

build.js

@@ -28,11 +28,11 @@
   var aliasToRealMap = {
     'all': 'every',
     'any': 'some',
-    'assign': 'extend',
     'collect': 'map',
     'detect': 'find',
     'drop': 'rest',
     'each': 'forEach',
+    'extend': 'assign',
     'foldl': 'reduce',
     'foldr': 'reduceRight',
     'head': 'first',
@@ -47,9 +47,9 @@
 
   /** Used to associate real names with their aliases */
   var realToAliasMap = {
+    'assign': ['extend'],
     'contains': ['include'],
     'every': ['all'],
-    'extend': ['assign'],
     'filter': ['select'],
     'find': ['detect'],
     'first': ['head', 'take'],
@@ -66,10 +66,11 @@
   /** Used to track function dependencies */
   var dependencyMap = {
     'after': [],
+    'assign': ['isArguments'],
     'bind': ['isFunction', 'isObject'],
     'bindAll': ['bind', 'functions'],
     'chain': ['mixin'],
-    'clone': ['extend', 'forEach', 'forOwn', 'isArguments', 'isObject', 'isPlainObject'],
+    'clone': ['assign', 'forEach', 'forOwn', 'isArguments', 'isObject', 'isPlainObject'],
     'compact': [],
     'compose': [],
     'contains': ['forEach', 'indexOf', 'isString'],
@@ -81,7 +82,6 @@
     'difference': ['indexOf'],
     'escape': [],
     'every': ['forEach', 'isArray'],
-    'extend': ['isArguments'],
     'filter': ['forEach', 'isArray'],
     'find': ['forEach'],
     'first': [],
@@ -231,7 +231,6 @@
 
   /** List of methods used by Underscore */
   var underscoreMethods = _.without.apply(_, [allMethods].concat([
-    'assign',
     'forIn',
     'forOwn',
     'isPlainObject',
@@ -346,7 +345,7 @@
       '    lodash csp           Build supporting default Content Security Policy restrictions',
       '    lodash legacy        Build tailored for older browsers without ES5 support',
       '    lodash mobile        Build with IE < 9 bug fixes & method compilation removed',
-      '    lodash strict        Build with `_.bindAll`, `_.defaults`, & `_.extend` in strict mode',
+      '    lodash strict        Build with `_.assign`, `_.bindAll`, & `_.defaults` in strict mode',
       '    lodash underscore    Build tailored for projects already using Underscore',
       '    lodash include=...   Comma separated method/category names to include in the build',
       '    lodash minus=...     Comma separated method/category names to remove from those included in the build',
@@ -892,7 +891,7 @@
     // flag used to specify skipping status updates normally logged to the console
     var isSilent = isStdOut || options.indexOf('-s') > -1 || options.indexOf('--silent') > -1;
 
-    // flag used to specify `_.bindAll`, `_.extend`, and `_.defaults` are
+    // flag used to specify `_.assign`, `_.bindAll`, and `_.defaults` are
     // constructed using the "use strict" directive
     var isStrict = options.indexOf('strict') > -1;
 
@@ -933,7 +932,7 @@
       return match
         ? Function('return {' + match[1].replace(/^{|}$/g, '') + '}')()
         : result;
-    }, _.extend(_.clone(_.templateSettings), {
+    }, _.assign(_.clone(_.templateSettings), {
       'moduleId': moduleId
     }));
 
@@ -998,7 +997,7 @@
         dependencyMap.template = ['defaults', 'escape'];
 
         if (useUnderscoreClone) {
-          dependencyMap.clone = ['extend', 'isArray'];
+          dependencyMap.clone = ['assign', 'isArray'];
         }
       }
       // add method names required by Backbone and Underscore builds
@@ -1068,7 +1067,7 @@
           source = source.replace(/^( *)function clone[\s\S]+?\n\1}/m, [
             '  function clone(value) {',
             '    return value && objectTypes[typeof value]',
-            '      ? (isArray(value) ? slice.call(value) : extend({}, value))',
+            '      ? (isArray(value) ? slice.call(value) : assign({}, value))',
             '      : value',
             '  }'
           ].join('\n'));
@@ -1108,9 +1107,9 @@
           '  }'
         ].join('\n'));
 
-        // replace `_.extend`
-        source = source.replace(/^( *)var extend *= *createIterator[\s\S]+?\);/m, [
-          '  function extend(object) {',
+        // replace `_.assign`
+        source = source.replace(/^( *)var assign *= *createIterator[\s\S]+?\);/m, [
+          '  function assign(object) {',
           '    if (!object) {',
           '      return object;',
           '    }',
@@ -1309,9 +1308,6 @@
         }
       });
 
-      if (!exposeAssign) {
-        source = removeFunction(source, 'assign');
-      }
       // remove `isArguments` fallback before `isArguments` is transformed by
       // other parts of the build process
       if (isRemoved(source, 'isArguments')) {
@@ -1379,11 +1375,14 @@
         });
 
         if (isUnderscore) {
-          // remove `_.forIn`, `_.forOwn`, and `_.isPlainObject` assignments
+          // remove `_.assign`, `_.forIn`, `_.forOwn`, and `_.isPlainObject` assignments
           (function() {
             var snippet = getMethodAssignments(source),
                 modified = snippet;
 
+            if (!exposeAssign) {
+              modified = modified.replace(/(?:\n *\/\/.*\s*)* *lodash\.assign *= *.+\n/, '');
+            }
             if (!exposeForIn) {
               modified = modified.replace(/(?:\n *\/\/.*\s*)* *lodash\.forIn *= *.+\n/, '');
             }

lodash.js

@@ -417,6 +417,16 @@
     'return result'
   );
 
+  /** Reusable iterator options for `assign` and `defaults` */
+  var assignIteratorOptions = {
+    'args': 'object, source, guard',
+    'top':
+      'for (var argsIndex = 1, argsLength = typeof guard == \'number\' ? 2 : arguments.length; argsIndex < argsLength; argsIndex++) {\n' +
+      '  if ((iteratee = arguments[argsIndex])) {',
+    'objectLoop': 'result[index] = value',
+    'bottom': '  }\n}'
+  };
+
   /**
    * Reusable iterator options shared by `forEach`, `forIn`, and `forOwn`.
    */
@@ -427,17 +437,6 @@
     'objectLoop': 'if (callback(value, index, collection) === false) return result'
   };
 
-  /** Reusable iterator options for `defaults`, and `extend` */
-  var extendIteratorOptions = {
-    'useHas': false,
-    'args': 'object, source, guard',
-    'top':
-      'for (var argsIndex = 1, argsLength = typeof guard == \'number\' ? 2 : arguments.length; argsIndex < argsLength; argsIndex++) {\n' +
-      '  if ((iteratee = arguments[argsIndex])) {',
-    'objectLoop': 'result[index] = value',
-    'bottom': '  }\n}'
-  };
-
   /** Reusable iterator options for `forIn` and `forOwn` */
   var forOwnIteratorOptions = {
     'arrayLoop': null
@@ -697,6 +696,25 @@
 
   /*--------------------------------------------------------------------------*/
 
+  /**
+   * Assigns own enumerable properties of source object(s) to the `destination`
+   * object. Subsequent sources will overwrite propery assignments of previous
+   * sources.
+   *
+   * @static
+   * @memberOf _
+   * @alias extend
+   * @category Objects
+   * @param {Object} object The destination object.
+   * @param {Object} [source1, source2, ...] The source objects.
+   * @returns {Object} Returns the destination object.
+   * @example
+   *
+   * _.assign({ 'name': 'moe' }, { 'age': 40 });
+   * // => { 'name': 'moe', 'age': 40 }
+   */
+  var assign = createIterator(assignIteratorOptions);
+
   /**
    * Checks if `value` is an `arguments` object.
    *
@@ -756,7 +774,7 @@
   });
 
   /**
-   * Iterates over `object`'s own enumerable properties, executing the `callback`
+   * Iterates over an object's own enumerable properties, executing the `callback`
    * for each property. The `callback` is bound to `thisArg` and invoked with three
    * arguments; (value, key, object). Callbacks may exit iteration early by explicitly
    * returning `false`.
@@ -915,7 +933,7 @@
     if (!isObj || !deep) {
       // don't clone functions
       return isObj
-        ? (isArr ? slice.call(value) : extend({}, value))
+        ? (isArr ? slice.call(value) : assign({}, value))
         : value;
     }
 
@@ -976,29 +994,11 @@
    * _.defaults(iceCream, { 'flavor': 'vanilla', 'sprinkles': 'rainbow' });
    * // => { 'flavor': 'chocolate', 'sprinkles': 'rainbow' }
    */
-  var defaults = createIterator(extendIteratorOptions, {
-    'objectLoop': 'if (result[index] == null) ' + extendIteratorOptions.objectLoop
+  var defaults = createIterator(assignIteratorOptions, {
+    'useHas': false,
+    'objectLoop': 'if (result[index] == null) ' + assignIteratorOptions.objectLoop
   });
 
-  /**
-   * Assigns enumerable properties of the source object(s) to the `destination`
-   * object. Subsequent sources will overwrite propery assignments of previous
-   * sources.
-   *
-   * @static
-   * @memberOf _
-   * @alias assign
-   * @category Objects
-   * @param {Object} object The destination object.
-   * @param {Object} [source1, source2, ...] The source objects.
-   * @returns {Object} Returns the destination object.
-   * @example
-   *
-   * _.extend({ 'name': 'moe' }, { 'age': 40 });
-   * // => { 'name': 'moe', 'age': 40 }
-   */
-  var extend = createIterator(extendIteratorOptions);
-
   /**
    * Creates a sorted array of all enumerable properties, own and inherited,
    * of `object` that have function values.
@@ -4079,6 +4079,7 @@
   lodash.VERSION = '0.9.2';
 
   // assign static methods
+  lodash.assign = assign;
   lodash.after = after;
   lodash.bind = bind;
   lodash.bindAll = bindAll;
@@ -4095,7 +4096,6 @@
   lodash.difference = difference;
   lodash.escape = escape;
   lodash.every = every;
-  lodash.extend = extend;
   lodash.filter = filter;
   lodash.find = find;
   lodash.first = first;
@@ -4177,11 +4177,11 @@
   // assign aliases
   lodash.all = every;
   lodash.any = some;
-  lodash.assign = extend;
   lodash.collect = map;
   lodash.detect = find;
   lodash.drop = rest;
   lodash.each = forEach;
+  lodash.extend = assign;
   lodash.foldl = reduce;
   lodash.foldr = reduceRight;
   lodash.head = first;

test/test-build.js

@@ -18,11 +18,11 @@
   var aliasToRealMap = {
     'all': 'every',
     'any': 'some',
-    'assign': 'extend',
     'collect': 'map',
     'detect': 'find',
     'drop': 'rest',
     'each': 'forEach',
+    'extend': 'assign',
     'foldl': 'reduce',
     'foldr': 'reduceRight',
     'head': 'first',
@@ -37,9 +37,9 @@
 
   /** Used to associate real names with their aliases */
   var realToAliasMap = {
+    'assign': ['extend'],
     'contains': ['include'],
     'every': ['all'],
-    'extend': ['assign'],
     'filter': ['select'],
     'find': ['detect'],
     'first': ['head', 'take'],
@@ -242,7 +242,6 @@
 
   /** List of methods used by Underscore */
   var underscoreMethods = _.without.apply(_, [allMethods].concat([
-    'assign',
     'forIn',
     'forOwn',
     'isPlainObject',

test/test.js

@@ -163,6 +163,42 @@
 
   /*--------------------------------------------------------------------------*/
 
+  QUnit.module('lodash.assign');
+
+  (function() {
+    test('should not error on `null` or `undefined` sources (test in IE < 9)', function() {
+      try {
+        deepEqual(_.assign({}, null, undefined, { 'a': 1 }), { 'a': 1 });
+      } catch(e) {
+        ok(false);
+      }
+    });
+
+    test('skips the prototype property of functions (test in Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1)', function() {
+      function Foo() {}
+      Foo.prototype.c = 3;
+
+      Foo.a = 1;
+      Foo.b = 2;
+
+      var expected = { 'a': 1, 'b': 2 };
+      deepEqual(_.assign({}, Foo), expected);
+
+      Foo.prototype = { 'c': 3 };
+      deepEqual(_.assign({}, Foo), expected);
+    });
+
+    test('should work with `_.reduce`', function() {
+      var actual = { 'a': 1},
+          array = [{ 'b': 2 }, { 'c': 3 }];
+
+      _.reduce(array, _.assign, actual);
+      deepEqual(actual, { 'a': 1, 'b': 2, 'c': 3});
+    });
+  }());
+
+  /*--------------------------------------------------------------------------*/
+
   QUnit.module('lodash.bind');
 
   (function() {
@@ -385,45 +421,9 @@
 
   /*--------------------------------------------------------------------------*/
 
-  QUnit.module('lodash.extend');
-
-  (function() {
-    test('should not error on `null` or `undefined` sources (test in IE < 9)', function() {
-      try {
-        deepEqual(_.extend({}, null, undefined, { 'a': 1 }), { 'a': 1 });
-      } catch(e) {
-        ok(false);
-      }
-    });
-
-    test('skips the prototype property of functions (test in Firefox < 3.6, Opera > 9.50 - Opera < 11.60, and Safari < 5.1)', function() {
-      function Foo() {}
-      Foo.prototype.c = 3;
-
-      Foo.a = 1;
-      Foo.b = 2;
-
-      var expected = { 'a': 1, 'b': 2 };
-      deepEqual(_.extend({}, Foo), expected);
-
-      Foo.prototype = { 'c': 3 };
-      deepEqual(_.extend({}, Foo), expected);
-    });
-
-    test('should work with `_.reduce`', function() {
-      var actual = { 'a': 1},
-          array = [{ 'b': 2 }, { 'c': 3 }];
-
-      _.reduce(array, _.extend, actual);
-      deepEqual(actual, { 'a': 1, 'b': 2, 'c': 3});
-    });
-  }());
-
-  /*--------------------------------------------------------------------------*/
-
   QUnit.module('strict mode checks');
 
-  _.each(['bindAll', 'defaults', 'extend'], function(methodName) {
+  _.each(['assign', 'bindAll', 'defaults'], function(methodName) {
     var func = _[methodName];
 
     test('lodash.' + methodName + ' should not throw strict mode errors', function() {