added hook for webpage.onResourceError

@@ -176,6 +176,17 @@ Proxy method for PhantomJS' WebPage#onResourceRequested() callback, but the curr
 
 .. index:: Step stack
 
+``onResourceError``
+-------------------------------------------------------------------------------
+
+**Type:** ``Function``
+
+**Default:** ``null``
+
+Proxy method for PhantomJS' WebPage#onResourceError() callback, but the current Casper instance is passed as first argument.
+
+.. index:: Step stack
+
 ``onStepComplete``
 -------------------------------------------------------------------------------
 

@@ -97,6 +97,7 @@ var Casper = function Casper(options) {
         onPageInitialized:   null,
         onResourceReceived:  null,
         onResourceRequested: null,
+        onResourceError:     null,
         onRunComplete:       function _onRunComplete() {
             this.exit();
         },
@@ -2544,6 +2545,12 @@ function createPage(casper) {
             casper.options.onResourceRequested.call(casper, casper, requestData, request);
         }
     };
+    page.onResourceError = function onResourceError(resourceError) {
+        casper.emit('resource.error', resourceError);
+        if (utils.isFunction(casper.options.onResourceError)) {
+            casper.options.onResourceError.call(casper, casper, resourceError);
+        }
+    };
     page.onUrlChanged = function onUrlChanged(url) {
         casper.log(f('url changed to "%s"', url), "debug");
         casper.navigationRequested = false;

@@ -50,6 +50,25 @@ casper.test.begin('onResourceRequested() & onResourceReceived() hook tests', 6,
     });
 });
 
+casper.test.begin('onResourceError() hook tests', 3, function(test) {
+    var error = null;
+    casper.options.onResourceError = function(self, resourceError) {
+        error = resourceError;
+    };
+
+    casper.start('tests/site/non-existant.html', function() {
+        var expectedPath = '/tests/site/non-existant.html';
+        test.assert(error !== null, 'onResourceError() called with error information');
+        test.assert(error.errorCode === 203, 'onResourceError() error code is correct');
+        test.assert((error.url.indexOf(expectedPath, error.url.length - expectedPath.length) !== -1), 'onResourceError() url is correct');
+    })
+
+    casper.run(function() {
+        this.options.onResourceError = undefined;
+        test.done();
+    });
+});
+
 casper.test.begin('onAlert() hook tests', 1, function(test) {
     var message;
     casper.options.onAlert = function(self, msg) {