JavaScript error handling

src/CurrentUrl.cpp

@@ -7,7 +7,7 @@ CurrentUrl::CurrentUrl(WebPageManager *manager, QStringList &arguments, QObject
 
 void CurrentUrl::start() {
   QStringList arguments;
-  QVariant result = page()->invokeCapybaraFunction("currentUrl", arguments);
+  QVariant result = page()->currentFrame()->evaluateJavaScript("window.location.toString()");
   QString url = result.toString();
   emitFinished(true, url);
 }

src/Find.cpp

@@ -2,19 +2,19 @@
 #include "SocketCommand.h"
 #include "WebPage.h"
 #include "WebPageManager.h"
+#include "InvocationResult.h"
 
 Find::Find(WebPageManager *manager, QStringList &arguments, QObject *parent) : SocketCommand(manager, arguments, parent) {
 }
 
 void Find::start() {
-  QString message;
-  QVariant result = page()->invokeCapybaraFunction("find", arguments());
+  InvocationResult result = page()->invokeCapybaraFunction("find", arguments());
 
-  if (result.isValid()) {
-    message = result.toString();
+  if (result.hasError())
+    return emitFinished(false, QString("Invalid XPath expression"));
+
+  QString message;
+  message = result.result().toString();
   emitFinished(true, message);
-  } else {
-    emitFinished(false, QString("Invalid XPath expression"));
-  }
 }
 

src/InvocationResult.cpp

@@ -0,0 +1,14 @@
+#include "InvocationResult.h"
+
+InvocationResult::InvocationResult(QVariant result, bool error) {
+  m_result = result;
+  m_error = error;
+}
+
+const QVariant &InvocationResult::result() const {
+  return m_result;
+}
+
+bool InvocationResult::hasError() {
+  return m_error;
+}

src/InvocationResult.h

@@ -0,0 +1,13 @@
+#include <QVariant>
+
+class InvocationResult {
+  public:
+    InvocationResult(QVariant result, bool error = false);
+    const QVariant &result() const;
+    bool hasError();
+
+  private:
+    QVariant m_result;
+    bool m_error;
+};
+

src/JavascriptInvocation.cpp

@@ -1,5 +1,6 @@
 #include "JavascriptInvocation.h"
 #include "WebPage.h"
+#include "InvocationResult.h"
 #include <QApplication>
 
 JavascriptInvocation::JavascriptInvocation(const QString &functionName, const QStringList &arguments, WebPage *page, QObject *parent) : QObject(parent) {
@@ -16,6 +17,23 @@ QStringList &JavascriptInvocation::arguments() {
   return m_arguments;
 }
 
+QVariantMap JavascriptInvocation::getError() {
+  return m_error;
+}
+
+void JavascriptInvocation::setError(QVariantMap error) {
+  m_error = error;
+}
+
+InvocationResult JavascriptInvocation::invoke(QWebFrame *frame) {
+  frame->addToJavaScriptWindowObject("CapybaraInvocation", this);
+  QVariant result = frame->evaluateJavaScript("Capybara.invoke()");
+  if (getError().isEmpty())
+    return InvocationResult(result);
+  else
+    return InvocationResult(getError(), true);
+}
+
 bool JavascriptInvocation::click(QWebElement element, int left, int top, int width, int height) {
   QRect elementBox(left, top, width, height);
   QRect viewport(QPoint(0, 0), m_page->viewportSize());

src/JavascriptInvocation.h

@@ -4,23 +4,28 @@
 #include <QWebElement>
 
 class WebPage;
+class InvocationResult;
 
 class JavascriptInvocation : public QObject {
   Q_OBJECT
   Q_PROPERTY(QString functionName READ functionName)
   Q_PROPERTY(QStringList arguments READ arguments)
+  Q_PROPERTY(QVariantMap error READ getError WRITE setError)
 
   public:
     JavascriptInvocation(const QString &functionName, const QStringList &arguments, WebPage *page, QObject *parent = 0);
     QString &functionName();
     QStringList &arguments();
     Q_INVOKABLE bool click(QWebElement element, int left, int top, int width, int height);
+    QVariantMap getError();
+    void setError(QVariantMap error);
+    InvocationResult invoke(QWebFrame *);
 
   private:
     QString m_functionName;
     QStringList m_arguments;
     WebPage *m_page;
     void execClick(QPoint mousePos);
-
+    QVariantMap m_error;
 };
 

src/Node.cpp

@@ -1,6 +1,7 @@
 #include "Node.h"
 #include "WebPage.h"
 #include "WebPageManager.h"
+#include "InvocationResult.h"
 
 Node::Node(WebPageManager *manager, QStringList &arguments, QObject *parent) : SocketCommand(manager, arguments, parent) {
 }
@@ -8,8 +9,12 @@ Node::Node(WebPageManager *manager, QStringList &arguments, QObject *parent) : S
 void Node::start() {
   QStringList functionArguments(arguments());
   QString functionName = functionArguments.takeFirst();
-  QVariant result = page()->invokeCapybaraFunction(functionName, functionArguments);
-  QString attributeValue = result.toString();
+  InvocationResult result = page()->invokeCapybaraFunction(functionName, functionArguments);
+
+  if (result.hasError())
+    return emitFinished(false);
+
+  QString attributeValue = result.result().toString();
   emitFinished(true, attributeValue);
 }
 

src/WebPage.cpp

@@ -4,6 +4,7 @@
 #include "NetworkAccessManager.h"
 #include "NetworkCookieJar.h"
 #include "UnsupportedContentHandler.h"
+#include "InvocationResult.h"
 #include <QResource>
 #include <iostream>
 #include <QWebSettings>
@@ -117,16 +118,13 @@ bool WebPage::shouldInterruptJavaScript() {
   return false;
 }
 
-QVariant WebPage::invokeCapybaraFunction(const char *name, const QStringList &arguments) {
+InvocationResult WebPage::invokeCapybaraFunction(const char *name, const QStringList &arguments) {
   QString qname(name);
-  QString objectName("CapybaraInvocation");
   JavascriptInvocation invocation(qname, arguments, this);
-  currentFrame()->addToJavaScriptWindowObject(objectName, &invocation);
-  QString javascript = QString("Capybara.invoke()");
-  return currentFrame()->evaluateJavaScript(javascript);
+  return invocation.invoke(currentFrame());
 }
 
-QVariant WebPage::invokeCapybaraFunction(QString &name, const QStringList &arguments) {
+InvocationResult WebPage::invokeCapybaraFunction(QString &name, const QStringList &arguments) {
   return invokeCapybaraFunction(name.toAscii().data(), arguments);
 }
 

src/WebPage.h

@@ -4,14 +4,15 @@
 
 class WebPageManager;
 class NetworkAccessManager;
+class InvocationResult;
 
 class WebPage : public QWebPage {
   Q_OBJECT
 
   public:
     WebPage(WebPageManager *, QObject *parent = 0);
-    QVariant invokeCapybaraFunction(const char *name, const QStringList &arguments);
-    QVariant invokeCapybaraFunction(QString &name, const QStringList &arguments);
+    InvocationResult invokeCapybaraFunction(const char *name, const QStringList &arguments);
+    InvocationResult invokeCapybaraFunction(QString &name, const QStringList &arguments);
     QString failureString();
     QString userAgentForUrl(const QUrl &url ) const;
     void setUserAgent(QString userAgent);

src/capybara.js

@@ -4,17 +4,17 @@ Capybara = {
   attachedFiles: [],
 
   invoke: function () {
+    try {
       return this[CapybaraInvocation.functionName].apply(this, CapybaraInvocation.arguments);
+    } catch (e) {
+      CapybaraInvocation.error = e;
+    }
   },
 
   find: function (xpath) {
     return this.findRelativeTo(document, xpath);
   },
 
-  currentUrl: function () {
-    return window.location.toString();
-  },
-
   findWithin: function (index, xpath) {
     return this.findRelativeTo(this.nodes[index], xpath);
   },

src/webkit_server.pro

@@ -56,7 +56,8 @@ HEADERS = \
   TimeoutCommand.h \
   SetUrlBlacklist.h \
   NoOpReply.h \
-  JsonSerializer.h
+  JsonSerializer.h \
+  InvocationResult.h
 
 SOURCES = \
   Version.cpp \
@@ -114,7 +115,8 @@ SOURCES = \
   TimeoutCommand.cpp \
   SetUrlBlacklist.cpp \
   NoOpReply.cpp \
-  JsonSerializer.cpp
+  JsonSerializer.cpp \
+  InvocationResult.cpp
 
 RESOURCES = webkit_server.qrc
 QT += network webkit