Add floating argument to _.random. [closes #354]

lodash.js

@@ -987,7 +987,7 @@
      *
      * @private
      * @param {*} value The value to clone.
-     * @param {boolean} [deep=false] A flag to indicate a deep clone.
+     * @param {boolean} [deep=false] Specify a deep clone.
      * @param {Function} [callback] The function to customize cloning values.
      * @param {Array} [stackA=[]] Tracks traversed source objects.
      * @param {Array} [stackB=[]] Associates clones with source counterparts.
@@ -1974,7 +1974,7 @@
      * @memberOf _
      * @category Objects
      * @param {*} value The value to clone.
-     * @param {boolean} [deep=false] A flag to indicate a deep clone.
+     * @param {boolean} [deep=false] Specify a deep clone.
      * @param {Function} [callback] The function to customize cloning values.
      * @param {*} [thisArg] The `this` binding of `callback`.
      * @returns {*} Returns the cloned `value`.
@@ -5957,35 +5957,56 @@
     /**
      * Produces a random number between `min` and `max` (inclusive). If only one
      * argument is provided a number between `0` and the given number will be
-     * returned.
+     * returned. If `floating` is truey or either `min` or `max` are floats a
+     * floating-point number will be returned instead of an integer.
      *
      * @static
      * @memberOf _
      * @category Utilities
      * @param {number} [min=0] The minimum possible value.
      * @param {number} [max=1] The maximum possible value.
+     * @param {boolean} [floating=false] Specify returning a floating-point number.
      * @returns {number} Returns a random number.
      * @example
      *
      * _.random(0, 5);
-     * // => a number between 0 and 5
+     * // => an integer between 0 and 5
      *
      * _.random(5);
-     * // => also a number between 0 and 5
+     * // => also an integer between 0 and 5
+     *
+     * _.random(5, true);
+     * // => a floating-point number between 0 and 5
+     *
+     * _.random(1.2, 5.2);
+     * // => a floating-point number between 1.2 and 5.2
      */
-    function random(min, max) {
-      if (min == null && max == null) {
+    function random(min, max, floating) {
+      var noMin = min == null,
+          noMax = max == null;
+
+      if (floating == null) {
+        if (typeof min == 'boolean' && noMax) {
+          floating = min;
+          min = 1;
+        }
+        else if (!noMax && typeof max == 'boolean') {
+          floating = max;
+          noMax = true;
+        }
+      }
+      if (noMin && noMax) {
         max = 1;
       }
       min = +min || 0;
-      if (max == null) {
+      if (noMax) {
         max = min;
         min = 0;
       } else {
         max = +max || 0;
       }
       var rand = nativeRandom();
-      return (min % 1 || max % 1)
+      return (floating || min % 1 || max % 1)
         ? min + nativeMin(rand * (max - min + parseFloat('1e-' + ((rand +'').length - 1))), max)
         : min + floor(rand * (max - min + 1));
     }