fix crash when detach()ing a debugger and then evaluating script print() function

Merge-request: 554
Reviewed-by: Kent Hansen <khansen@trolltech.com>

2 files changed, 14 insertions, 7 deletions

diff --git a/src/scripttools/debugging/qscriptdebuggerbackend.cpp b/src/scripttools/debugging/qscriptdebuggerbackend.cpp
index da9d50e..c7577d6 100644
--- a/src/scripttools/debugging/qscriptdebuggerbackend.cpp
+++ b/src/scripttools/debugging/qscriptdebuggerbackend.cpp
@@ -412,11 +412,14 @@ void QScriptDebuggerBackend::attachTo(QScriptEngine *engine)
     detach();
     d->agent = new QScriptDebuggerAgent(d, engine);
     QScriptValue global = engine->globalObject();
+    d->origTraceFunction = global.property(QString::fromLatin1("print"));
     global.setProperty(QString::fromLatin1("print"), traceFunction());
 //    global.setProperty(QString::fromLatin1("qAssert"), assertFunction());
+    d->origFileNameFunction = global.property(QString::fromLatin1("__FILE__"));
     global.setProperty(QString::fromLatin1("__FILE__"), fileNameFunction(),
                        QScriptValue::PropertyGetter | QScriptValue::PropertySetter
                        | QScriptValue::ReadOnly);
+    d->origLineNumberFunction = global.property(QString::fromLatin1("__LINE__"));
     global.setProperty(QString::fromLatin1("__LINE__"), lineNumberFunction(),
                        QScriptValue::PropertyGetter | QScriptValue::PropertySetter
                        | QScriptValue::ReadOnly);
@@ -438,13 +441,13 @@ void QScriptDebuggerBackend::detach()
         if (eng && eng->agent() == d->agent) {
             eng->setAgent(0);
             QScriptValue global = eng->globalObject();
-            if (global.property(QString::fromLatin1("print")).strictlyEquals(traceFunction()))
-                global.setProperty(QString::fromLatin1("print"), QScriptValue());
+            global.setProperty(QString::fromLatin1("print"), d->origTraceFunction);
+            d->origTraceFunction = QScriptValue();
 //            global.setProperty(QString::fromLatin1("qAssert"), QScriptValue());
-            if (global.property(QString::fromLatin1("__FILE__")).strictlyEquals(fileNameFunction()))
-                global.setProperty(QString::fromLatin1("__FILE__"), QScriptValue());
-            if (global.property(QString::fromLatin1("__LINE__")).strictlyEquals(lineNumberFunction()))
-                global.setProperty(QString::fromLatin1("__LINE__"), QScriptValue());
+            global.setProperty(QString::fromLatin1("__FILE__"), d->origFileNameFunction);
+            d->origFileNameFunction = QScriptValue();
+            global.setProperty(QString::fromLatin1("__LINE__"), d->origLineNumberFunction);
+            d->origLineNumberFunction = QScriptValue();
             d->agent->nullifyBackendPointer();
             d->agent = 0; // agent is owned by engine
         }
diff --git a/src/scripttools/debugging/qscriptdebuggerbackend_p_p.h b/src/scripttools/debugging/qscriptdebuggerbackend_p_p.h
index de18304..a356762 100644
--- a/src/scripttools/debugging/qscriptdebuggerbackend_p_p.h
+++ b/src/scripttools/debugging/qscriptdebuggerbackend_p_p.h
@@ -57,6 +57,7 @@
 
 #include <QtCore/qhash.h>
 #include <QtCore/qlist.h>
+#include <QtScript/qscriptvalue.h>
 
 #include "qscriptdebuggerbackend_p.h"
 
@@ -66,7 +67,6 @@ class QEvent;
 class QString;
 class QScriptContext;
 class QScriptEngine;
-class QScriptValue;
 class QScriptValueIterator;
 class QScriptObjectSnapshot;
 class QScriptDebuggerAgent;
@@ -126,6 +126,10 @@ public:
     QObject *eventReceiver;
 
     QScriptDebuggerBackend *q_ptr;
+
+    QScriptValue origTraceFunction;
+    QScriptValue origFileNameFunction;
+    QScriptValue origLineNumberFunction;
 };
 
 QT_END_NAMESPACE