enhanced utils.betterTypeOf() to handle `undefined` and `null` values

@@ -31,7 +31,8 @@ casper.evaluate(function(a, b) {
 - fixed [#274](https://github.com/n1k0/casperjs/issues/274) - some headers couldn't be set
 - fixed [#277](https://github.com/n1k0/casperjs/issues/277) - multiline support in `ClientUtils.echo()`
 - fixed [#282](https://github.com/n1k0/casperjs/issues/282) - added support for remote client scripts loading with a new `remoteScripts` casper option
-- merged [#290](https://github.com/n1k0/casperjs/issues/#290) - add a simplistic RPM spec file to make it easier to (un)install casperjs
+- fixed [#290](https://github.com/n1k0/casperjs/issues/#290) - add a simplistic RPM spec file to make it easier to (un)install casperjs
+- fixed [`utils.betterTypeOf()`](http://casperjs.org/api.html#casper.betterTypeOf) to properly handle `undefined` and `null` values
 - fixed `Casper.die()` and `Casper.evaluateOrDie()` were not printing the error onto the console
 - added [`Casper.getFormValues()`](http://casperjs.org/api.html#casper.getFormValues) to check for the field values of a given form
 - added [`Tester.assertTextDoesntExist()`](http://casperjs.org/api.html#tester.assertTextDoesntExist)

@@ -34,16 +34,26 @@
  * Provides a better typeof operator equivalent, able to retrieve the array
  * type.
  *
+ * CAVEAT: this function does not necessarilly map to classical js "type" names,
+ * notably a `null` will map to "null" instead of "object".
+ *
  * @param  mixed  input
  * @return String
  * @see    http://javascriptweblog.wordpress.com/2011/08/08/fixing-the-javascript-typeof-operator/
  */
 function betterTypeOf(input) {
     "use strict";
-    try {
-        return Object.prototype.toString.call(input).match(/^\[object\s(.*)\]$/)[1].toLowerCase();
-    } catch (e) {
-        return typeof input;
+    switch (input) {
+        case undefined:
+            return 'undefined';
+        case null:
+            return 'null';
+        default:
+        try {
+            return Object.prototype.toString.call(input).match(/^\[object\s(.*)\]$/)[1].toLowerCase();
+        } catch (e) {
+            return typeof input;
+        }
     }
 }
 exports.betterTypeOf = betterTypeOf;

@@ -4,6 +4,26 @@ var utils = require('utils'),
     t = casper.test,
     x = require('casper').selectXPath;
 
+t.comment('betterTypeOf()');
+(function() {
+    var testCases = [
+        {subject: 1, expected: 'number'},
+        {subject: '1', expected: 'string'},
+        {subject: {}, expected: 'object'},
+        {subject: [], expected: 'array'},
+        {subject: undefined, expected: 'undefined'},
+        {subject: null, expected: 'null'},
+        {subject: function(){}, expected: 'function'},
+        {subject: window, expected: 'domwindow'},
+        {subject: new Date(), expected: 'date'},
+        {subject: new RegExp(), expected: 'regexp'}
+    ];
+    testCases.forEach(function(testCase) {
+        t.assertEquals(utils.betterTypeOf(testCase.subject), testCase.expected,
+            require('utils').format('betterTypeOf() detects expected type "%s"', testCase.subject));
+    });
+})();
+
 t.comment('cleanUrl()');
 (function() {
     var testCases = {