Add _.negate, _.keysIn and _.valuesIn.

lodash.js

@@ -4568,9 +4568,7 @@
      */
     function reject(collection, predicate, thisArg) {
       predicate = lodash.createCallback(predicate, thisArg, 3);
-      return filter(collection, function(value, index, collection) {
-        return !predicate(value, index, collection);
-      });
+      return filter(collection, negate(predicate));
     }
 
     /**
@@ -5930,26 +5928,21 @@
      *   this.y = 0;
      * }
      *
-     * Shape.prototype.move = function(x, y) {
-     *   this.x += x;
-     *   this.y += y;
-     * };
+     * Shape.prototype.z = 0;
      *
      * _.forInRight(new Shape, function(value, key) {
      *   console.log(key);
      * });
-     * // => logs 'move', 'y', and 'x' assuming `_.forIn ` logs 'x', 'y', and 'move'
+     * // => logs 'z', 'y', and 'x' assuming `_.forIn ` logs 'x', 'y', and 'z'
      */
     function forInRight(object, callback, thisArg) {
-      var pairs = [];
-      baseForIn(object, function(value, key) {
-        pairs.push(key, value);
-      });
+      var props = keysIn(object),
+          length = props.length;
 
-      var length = pairs.length;
       callback = baseCreateCallback(callback, thisArg, 3);
       while (length--) {
-        if (callback(pairs[length--], pairs[length], object) === false) {
+        var prop = props[length];
+        if (callback(object[prop], prop, object) === false) {
           break;
         }
       }
@@ -6568,6 +6561,35 @@
       return nativeKeys(object);
     };
 
+    /**
+     * Creates an array of the own and inherited enumerable property names of `object`.
+     *
+     * @static
+     * @memberOf _
+     * @category Objects
+     * @param {Object} object The object to inspect.
+     * @returns {Array} Returns the array of property names.
+     * @example
+     *
+     * function Shape() {
+     *   this.x = 0;
+     *   this.y = 0;
+     * }
+     *
+     * Shape.prototype.z = 0;
+     *
+     * _.keysIn(new Shape);
+     * // => ['x', 'y', 'z'] (property order is not guaranteed across environments)
+     */
+    function keysIn(object) {
+      var result = [];
+
+      baseForIn(object, function(value, key) {
+        result.push(key);
+      });
+      return result;
+    }
+
     /**
      * Creates an object with the same keys as `object` and values generated by
      * running each own enumerable property of `object` through the callback.
@@ -6722,37 +6744,17 @@
      * // => { 'name': 'fred' }
      */
     function omit(object, predicate, thisArg) {
-      var result = {};
-
-      if (typeof predicate != 'function') {
-        var omitProps = baseFlatten(arguments, true, false, 1),
-            length = omitProps.length;
-
-        while (length--) {
-          omitProps[length] = String(omitProps[length]);
-        }
-        var props = [];
-        baseForIn(object, function(value, key) {
-          props.push(key);
-        });
-
-        var index = -1;
-        props = baseDifference(props, omitProps);
-        length = props.length;
-
-        while (++index < length) {
-          var key = props[index];
-          result[key] = object[key];
-        }
-      } else {
+      if (typeof predicate == 'function') {
         predicate = lodash.createCallback(predicate, thisArg, 3);
-        baseForIn(object, function(value, key, object) {
-          if (!predicate(value, key, object)) {
-            result[key] = value;
-          }
-        });
+        return pick(object, negate(predicate));
       }
-      return result;
+      var omitProps = baseFlatten(arguments, true, false, 1),
+          length = omitProps.length;
+
+      while (length--) {
+        omitProps[length] = String(omitProps[length]);
+      }
+      return pick(object, baseDifference(keysIn(object),  omitProps));
     }
 
     /**
@@ -6918,6 +6920,36 @@
       return result;
     }
 
+    /**
+     * Creates an array composed of the own and inherited enumerable property
+     * values of `object`.
+     *
+     * @static
+     * @memberOf _
+     * @category Objects
+     * @param {Object} object The object to inspect.
+     * @returns {Array} Returns the new array of property values.
+     * @example
+     *
+     * function Shape(x, y) {
+     *   this.x = x;
+     *   this.y = y;
+     * }
+     *
+     * Shape.prototype.z = 0;
+     *
+     * _.valuesIn(new Shape(2, 1));
+     * // => [2, 1, 0] (property order is not guaranteed across environments)
+     */
+    function valuesIn(object) {
+      var result = [];
+
+      baseForIn(object, function(value) {
+        result.push(value);
+      });
+      return result;
+    }
+
     /*--------------------------------------------------------------------------*/
 
     /**
@@ -7842,6 +7874,33 @@
       }
     }
 
+    /**
+     * Creates a function that negates the result of `func`. The `func` function
+     * is executed with the `this` binding and arguments of the created function.
+     *
+     * @static
+     * @memberOf _
+     * @category Utilities
+     * @param {Function} func The function to negate.
+     * @returns {Function} Returns the new function.
+     * @example
+     *
+     * function isEven(num) {
+     *   return num % 2 == 0;
+     * }
+     *
+     * _.filter([1, 2, 3, 4, 5, 6], _.negate(isEven));
+     * // => [1, 3, 5]
+     */
+    function negate(func) {
+      if (!isFunction(func)) {
+        throw new TypeError;
+      }
+      return function() {
+        return !func.apply(this, arguments);
+      };
+    }
+
     /**
      * Reverts the '_' variable to its previous value and returns a reference to
      * the `lodash` function.
@@ -8148,6 +8207,7 @@
     lodash.invert = invert;
     lodash.invoke = invoke;
     lodash.keys = keys;
+    lodash.keysIn = keysIn;
     lodash.map = map;
     lodash.mapValues = mapValues;
     lodash.matches = matches;
@@ -8155,6 +8215,7 @@
     lodash.memoize = memoize;
     lodash.merge = merge;
     lodash.min = min;
+    lodash.negate = negate;
     lodash.omit = omit;
     lodash.once = once;
     lodash.pairs = pairs;
@@ -8180,6 +8241,7 @@
     lodash.union = union;
     lodash.uniq = uniq;
     lodash.values = values;
+    lodash.valuesIn = valuesIn;
     lodash.where = where;
     lodash.without = without;
     lodash.wrap = wrap;

test/test.js

@@ -9264,6 +9264,7 @@
       'defer',
       'delay',
       'memoize',
+      'negate',
       'once',
       'partial',
       'partialRight',
@@ -9274,7 +9275,7 @@
 
     var acceptFalsey = _.difference(allMethods, rejectFalsey);
 
-    test('should accept falsey arguments', 182, function() {
+    test('should accept falsey arguments', 184, function() {
       var emptyArrays = _.map(falsey, function() { return []; }),
           isExposed = '_' in root,
           oldDash = root._;
@@ -9343,7 +9344,7 @@
       });
     });
 
-    test('should reject falsey arguments', 14, function() {
+    test('should reject falsey arguments', 15, function() {
       _.forEach(rejectFalsey, function(methodName) {
         var expected = _.map(falsey, function() { return true; }),
             func = _[methodName];