Fix JS interrupt

fix_js_interrupt.patch

From 96832b2ef7376b20598c3ae372b490f52c80f28d Mon Sep 17 00:00:00 2001
From: Vitaliy Slobodin <vitaliy.slobodin@gmail.com>
Date: Wed, 3 Apr 2013 22:06:38 +0400
Subject: [PATCH] Define the new page callback for interrupting a long-running
 JavaScript

---
 src/modules/webpage.js |  3 +++
 src/webpage.cpp        | 37 +++++++++++++++++++++++++++++++++++--
 src/webpage.h          |  2 ++
 3 files changed, 40 insertions(+), 2 deletions(-)

diff --git a/src/modules/webpage.js b/src/modules/webpage.js
index e2f52c6..e8e6369 100644
--- a/src/modules/webpage.js
+++ b/src/modules/webpage.js
@@ -468,6 +468,9 @@ function decorateNewPage(opts, page) {
     // @see https://developer.mozilla.org/en/DOM/window.prompt
     definePageCallbackHandler(page, handlers, "onPrompt", "_getJsPromptCallback");
 
+    // Calls from within the page when some javascript code running to long
+    definePageCallbackHandler(page, handlers, "onShouldInterruptJs", "_getJsInterruptCallback");
+
     page.event = {};
     page.event.modifier = {
         shift:  0x02000000,
diff --git a/src/webpage.cpp b/src/webpage.cpp
index c76a4b8..3ba71cf 100644
--- a/src/webpage.cpp
+++ b/src/webpage.cpp
@@ -112,8 +112,8 @@ public:
 
 public slots:
     bool shouldInterruptJavaScript() {
-        QApplication::processEvents(QEventLoop::AllEvents, 42);
-        return false;
+        bool willInterrupt = m_webPage->javascriptInterrupt();
+        return willInterrupt;
     }
 
 protected:
@@ -251,6 +251,7 @@ public:
         , m_filePickerCallback(NULL)
         , m_jsConfirmCallback(NULL)
         , m_jsPromptCallback(NULL)
+        , m_jsInterruptCallback(NULL)
     {
     }
 
@@ -289,6 +290,15 @@ public:
         }
         return m_jsPromptCallback;
     }
+    
+    QObject *getJsInterruptCallback() {
+        qDebug() << "WebpageCallbacks - getJsInterruptCallback";
+
+        if (!m_jsInterruptCallback) {
+            m_jsInterruptCallback = new Callback(this);
+        }
+        return m_jsInterruptCallback;
+    }
 
 public slots:
     QVariant call(const QVariantList &arguments) {
@@ -303,6 +313,7 @@ private:
     Callback *m_filePickerCallback;
     Callback *m_jsConfirmCallback;
     Callback *m_jsPromptCallback;
+    Callback *m_jsInterruptCallback;
 
     friend class WebPage;
 };
@@ -729,6 +740,19 @@ bool WebPage::javaScriptPrompt(const QString &msg, const QString &defaultValue,
     return false;
 }
 
+bool WebPage::javascriptInterrupt()
+{
+    if (m_callbacks->m_jsInterruptCallback) {
+        QVariant res = m_callbacks->m_jsInterruptCallback->call(QVariantList());
+
+        if (res.canConvert<bool>()) {
+            return res.toBool();
+        }
+    }
+
+    return false;
+}
+
 void WebPage::finish(bool ok)
 {
     QString status = ok ? "success" : "fail";
@@ -1293,6 +1317,15 @@ QObject *WebPage::_getJsPromptCallback()
     return m_callbacks->getJsPromptCallback();
 }
 
+QObject *WebPage::_getJsInterruptCallback()
+{
+    if (!m_callbacks) {
+        m_callbacks = new WebpageCallbacks(this);
+    }
+
+    return m_callbacks->getJsInterruptCallback();
+}
+
 void WebPage::sendEvent(const QString &type, const QVariant &arg1, const QVariant &arg2, const QString &mouseButton, const QVariant &modifierArg)
 {
     Qt::KeyboardModifiers keyboardModifiers(modifierArg.toInt());
diff --git a/src/webpage.h b/src/webpage.h
index e065bb4..f8d022b 100644
--- a/src/webpage.h
+++ b/src/webpage.h
@@ -258,6 +258,7 @@ public slots:
     QObject *_getFilePickerCallback();
     QObject *_getJsConfirmCallback();
     QObject *_getJsPromptCallback();
+    QObject *_getJsInterruptCallback();
     void _uploadFile(const QString &selector, const QStringList &fileNames);
     void sendEvent(const QString &type, const QVariant &arg1 = QVariant(), const QVariant &arg2 = QVariant(), const QString &mouseButton = QString(), const QVariant &modifierArg = QVariant());
 
@@ -497,6 +498,7 @@ private:
     QString filePicker(const QString &oldFile);
     bool javaScriptConfirm(const QString &msg);
     bool javaScriptPrompt(const QString &msg, const QString &defaultValue, QString *result);
+    bool javascriptInterrupt();
 
 private:
     CustomPage *m_customWebPage;
-- 
1.8.1.msysgit.1
 

@vitallium - I've been testing with this patch for a while and I have not found any issues. I notice that you also have a branch with this code in. I would like to see this pushed if possible.