Make _.at an "Object" method.

lodash.src.js

@@ -1528,29 +1528,21 @@
     }
 
     /**
-     * The base implementation of `_.at` without support for string collections
-     * and individual key arguments.
+     * The base implementation of `_.at` without support for individual path arguments.
      *
      * @private
-     * @param {Array|Object} collection The collection to iterate over.
-     * @param {number[]|string[]} props The property names or indexes of elements to pick.
+     * @param {Object} object The object to iterate over.
+     * @param {string[]} paths The property paths of elements to pick.
      * @returns {Array} Returns the new array of picked elements.
      */
-    function baseAt(collection, props) {
+    function baseAt(object, paths) {
       var index = -1,
-          isNil = collection == null,
-          isArr = !isNil && isArrayLike(collection),
-          length = isArr ? collection.length : 0,
-          propsLength = props.length,
-          result = Array(propsLength);
+          isNil = object == null,
+          length = paths.length,
+          result = Array(length);
 
-      while(++index < propsLength) {
-        var key = props[index];
-        if (isArr) {
-          result[index] = isIndex(key, length) ? collection[key] : undefined;
-        } else {
-          result[index] = isNil ? undefined : collection[key];
-        }
+      while(++index < length) {
+        result[index] = isNil ? undefined : get(object, paths[index]);
       }
       return result;
     }
@@ -2419,9 +2411,13 @@
       var length = array ? indexes.length : 0;
       while (length--) {
         var index = indexes[length];
-        if (index != previous && isIndex(index)) {
+        if (index != previous) {
           var previous = index;
-          splice.call(array, index, 1);
+          if (isIndex(index)) {
+            splice.call(array, index, 1);
+          } else {
+            delete array[index];
+          }
         }
       }
       return array;
@@ -4783,8 +4779,8 @@
     }
 
     /**
-     * Removes elements from `array` corresponding to the given indexes and returns
-     * an array of the removed elements.
+     * Removes elements from `array` corresponding to `indexes` and returns an
+     * array of removed elements.
      *
      * **Note:** Unlike `_.at`, this method mutates `array`.
      *
@@ -5729,30 +5725,6 @@
 
     /*------------------------------------------------------------------------*/
 
-    /**
-     * Creates an array of elements corresponding to the given keys, or indexes,
-     * of `collection`. Keys may be specified as individual arguments or as arrays
-     * of keys.
-     *
-     * @static
-     * @memberOf _
-     * @category Collection
-     * @param {Array|Object|string} collection The collection to iterate over.
-     * @param {...(number|number[]|string|string[])} [props] The property names
-     *  or indexes of elements to pick, specified individually or in arrays.
-     * @returns {Array} Returns the new array of picked elements.
-     * @example
-     *
-     * _.at(['a', 'b', 'c'], [0, 2]);
-     * // => ['a', 'c']
-     *
-     * _.at(['barney', 'fred', 'pebbles'], 0, 2);
-     * // => ['barney', 'pebbles']
-     */
-    var at = restParam(function(collection, props) {
-      return baseAt(collection, baseFlatten(props));
-    });
-
     /**
      * Creates an object composed of keys generated from the results of running
      * each element of `collection` through `iteratee`. The corresponding value
@@ -8497,6 +8469,30 @@
       copyObjectWith(source, keys(source), customizer, object);
     });
 
+    /**
+     * Creates an array of values corresponding to `paths` of `object`.
+     *
+     * @static
+     * @memberOf _
+     * @category Object
+     * @param {Object} object The object to iterate over.
+     * @param {...(string|string[])} [paths] The property paths of elements to pick,
+     *  specified individually or in arrays.
+     * @returns {Array} Returns the new array of picked elements.
+     * @example
+     *
+     * var object = { 'a': [{ 'b': { 'c': 3 } }, 4] };
+     *
+     * _.at(object, ['a[0].b.c', 'a[1]']);
+     * // => [3, 4]
+     *
+     * _.at(['a', 'b', 'c'], 0, 2);
+     * // => ['a', 'c']
+     */
+    var at = restParam(function(object, paths) {
+      return baseAt(object, baseFlatten(paths));
+    });
+
     /**
      * Creates an object that inherits from the given `prototype` object. If a
      * `properties` object is provided its own enumerable properties are assigned

test/test.js

@@ -1027,6 +1027,12 @@
     var args = arguments,
         array = ['a', 'b', 'c'];
 
+    _.each(empties, function(value) {
+      if (value !== 0) {
+        array[value] = 1;
+      }
+    });
+
     array['1.1'] = array['-1'] = 1;
 
     test('should return the elements corresponding to the specified keys', 1, function() {
@@ -1039,12 +1045,12 @@
       deepEqual(actual, ['c', undefined, 'a']);
     });
 
-    test('should use `undefined` for non-index keys on array-like values', 1, function() {
+    test('should work with non-index keys on array-like values', 1, function() {
       var values = _.reject(empties, function(value) {
         return value === 0 || _.isArray(value);
       }).concat(-1, 1.1);
 
-      var expected = _.map(values, _.constant(undefined)),
+      var expected = _.map(values, _.constant(1)),
           actual = _.at(array, values);
 
       deepEqual(actual, expected);
@@ -1060,19 +1066,19 @@
       deepEqual(actual, ['d', 'a', 'c']);
     });
 
-    test('should work with a falsey `collection` argument when keys are provided', 1, function() {
+    test('should work with a falsey `object` argument when keys are provided', 1, function() {
       var expected = _.map(falsey, _.constant(Array(4)));
 
-      var actual = _.map(falsey, function(collection) {
+      var actual = _.map(falsey, function(object) {
         try {
-          return _.at(collection, 0, 1, 'pop', 'push');
+          return _.at(object, 0, 1, 'pop', 'push');
         } catch(e) {}
       });
 
       deepEqual(actual, expected);
     });
 
-    test('should work with an `arguments` object for `collection`', 1, function() {
+    test('should work with an `arguments` object for `object`', 1, function() {
       var actual = _.at(args, [2, 0]);
       deepEqual(actual, [3, 1]);
     });
@@ -1082,7 +1088,7 @@
       deepEqual(actual, [2, 3, 4]);
     });
 
-    test('should work with an object for `collection`', 1, function() {
+    test('should work with an object for `object`', 1, function() {
       var actual = _.at({ 'a': 1, 'b': 2, 'c': 3 }, ['c', 'a']);
       deepEqual(actual, [3, 1]);
     });
@@ -1099,9 +1105,9 @@
       'literal': 'abc',
       'object': Object('abc')
     },
-    function(collection, key) {
-      test('should work with a string ' + key + ' for `collection`', 1, function() {
-        deepEqual(_.at(collection, [2, 0]), ['c', 'a']);
+    function(object, key) {
+      test('should work with a string ' + key + ' for `object`', 1, function() {
+        deepEqual(_.at(object, [2, 0]), ['c', 'a']);
       });
     });
   }(1, 2, 3));
@@ -12342,23 +12348,6 @@
       deepEqual(actual, ['c', undefined, 'a']);
     });
 
-    test('should ignore non-index keys', 2, function() {
-      var array = ['a', 'b', 'c'],
-          clone = array.slice();
-
-      array['1.1'] = array['-1'] = 1;
-
-      var values = _.reject(empties, function(value) {
-        return value === 0 || _.isArray(value);
-      }).concat(-1, 1.1, 'pop', 'push');
-
-      var expected = _.map(values, _.constant(undefined)),
-          actual = _.pullAt(array, values);
-
-      deepEqual(actual, expected);
-      deepEqual(array, clone);
-    });
-
     test('should return an empty array when no indexes are provided', 4, function() {
       var array = ['a', 'b', 'c'],
           actual = _.pullAt(array);