1 files changed, 42 insertions, 25 deletions

diff --git a/src/corelib/kernel/qmetaobject.cpp b/src/corelib/kernel/qmetaobject.cpp
index 5be94429b4..dcebe0b00a 100644
--- a/src/corelib/kernel/qmetaobject.cpp
+++ b/src/corelib/kernel/qmetaobject.cpp
@@ -163,11 +163,6 @@ static inline const char *rawStringData(const QMetaObject *mo, int index)
     return stringData(mo, index).data();
 }
 
-static inline int stringSize(const QMetaObject *mo, int index)
-{
-    return stringData(mo, index).size();
-}
-
 static inline QByteArray typeNameFromTypeInfo(const QMetaObject *mo, uint typeInfo)
 {
     if (typeInfo & IsUnresolvedType) {
@@ -308,6 +303,11 @@ int QMetaObject::metacall(QObject *object, Call cl, int idx, void **argv)
         return object->qt_metacall(cl, idx, argv);
 }
 
+static inline const char *objectClassName(const QMetaObject *m)
+{
+    return rawStringData(m, priv(m->d.data)->className);
+}
+
 /*!
     Returns the class name.
 
@@ -315,7 +315,7 @@ int QMetaObject::metacall(QObject *object, Call cl, int idx, void **argv)
 */
 const char *QMetaObject::className() const
 {
-    return rawStringData(this, 0);
+    return objectClassName(this);
 }
 
 /*!
@@ -369,7 +369,7 @@ const QObject *QMetaObject::cast(const QObject *obj) const
 */
 QString QMetaObject::tr(const char *s, const char *c, int n) const
 {
-    return QCoreApplication::translate(rawStringData(this, 0), s, c, n);
+    return QCoreApplication::translate(objectClassName(this), s, c, n);
 }
 #endif // QT_NO_TRANSLATION
 
@@ -728,7 +728,7 @@ int QMetaObjectPrivate::indexOfSignalRelative(const QMetaObject **baseObject,
             QMetaMethod conflictMethod = m->d.superdata->method(conflict);
             qWarning("QMetaObject::indexOfSignal: signal %s from %s redefined in %s",
                      conflictMethod.methodSignature().constData(),
-                     rawStringData(m->d.superdata, 0), rawStringData(m, 0));
+                     objectClassName(m->d.superdata), objectClassName(m));
         }
      }
  #endif
@@ -938,7 +938,7 @@ bool QMetaObjectPrivate::checkConnectArgs(const QMetaMethodPrivate *signal,
 static const QMetaObject *QMetaObject_findMetaObject(const QMetaObject *self, const char *name)
 {
     while (self) {
-        if (strcmp(rawStringData(self, 0), name) == 0)
+        if (strcmp(objectClassName(self), name) == 0)
             return self;
         if (self->d.relatedMetaObjects) {
             Q_ASSERT(priv(self->d.data)->revision >= 2);
@@ -1117,7 +1117,7 @@ QMetaProperty QMetaObject::property(int index) const
             result.menum = enumerator(indexOfEnumerator(type));
             if (!result.menum.isValid()) {
                 const char *enum_name = type;
-                const char *scope_name = rawStringData(this, 0);
+                const char *scope_name = objectClassName(this);
                 char *scope_buffer = 0;
 
                 const char *colon = strrchr(enum_name, ':');
@@ -1339,6 +1339,27 @@ QByteArray QMetaObject::normalizedSignature(const char *method)
 enum { MaximumParamCount = 11 }; // up to 10 arguments + 1 return value
 
 /*!
+    Returns the signatures of all methods whose name matches \a nonExistentMember,
+    or an empty QByteArray if there are no matches.
+*/
+static inline QByteArray findMethodCandidates(const QMetaObject *metaObject, const char *nonExistentMember)
+{
+    QByteArray candidateMessage;
+    // Prevent full string comparison in every iteration.
+    const QByteArray memberByteArray = nonExistentMember;
+    for (int i = 0; i < metaObject->methodCount(); ++i) {
+        const QMetaMethod method = metaObject->method(i);
+        if (method.name() == memberByteArray)
+            candidateMessage.append("    " + method.methodSignature() + '\n');
+    }
+    if (!candidateMessage.isEmpty()) {
+        candidateMessage.prepend("\nCandidates are:\n");
+        candidateMessage.chop(1);
+    }
+    return candidateMessage;
+}
+
+/*!
     Invokes the \a member (a signal or a slot name) on the object \a
     obj. Returns \c true if the member could be invoked. Returns \c false
     if there is no such member or the parameters did not match.
@@ -1455,8 +1476,9 @@ bool QMetaObject::invokeMethod(QObject *obj,
     }
 
     if (idx < 0 || idx >= meta->methodCount()) {
-        qWarning("QMetaObject::invokeMethod: No such method %s::%s",
-                 meta->className(), sig.constData());
+        // This method doesn't belong to us; print out a nice warning with candidates.
+        qWarning("QMetaObject::invokeMethod: No such method %s::%s%s",
+                 meta->className(), sig.constData(), findMethodCandidates(meta, member).constData());
         return false;
     }
     QMetaMethod method = meta->method(idx);
@@ -2412,7 +2434,7 @@ bool QMetaEnum::isFlag() const
 */
 const char *QMetaEnum::scope() const
 {
-    return mobj?rawStringData(mobj, 0) : 0;
+    return mobj ? objectClassName(mobj) : 0;
 }
 
 /*!
@@ -2444,7 +2466,8 @@ int QMetaEnum::keyToValue(const char *key, bool *ok) const
     int count = mobj->d.data[handle + 2];
     int data = mobj->d.data[handle + 3];
     for (int i = 0; i < count; ++i) {
-        if ((!scope || (stringSize(mobj, 0) == int(scope) && strncmp(qualified_key, rawStringData(mobj, 0), scope) == 0))
+        const QByteArray className = stringData(mobj, priv(mobj->d.data)->className);
+        if ((!scope || (className.size() == int(scope) && strncmp(qualified_key, className.constData(), scope) == 0))
              && strcmp(key, rawStringData(mobj, mobj->d.data[data + 2*i])) == 0) {
             if (ok != 0)
                 *ok = true;
@@ -2512,12 +2535,14 @@ int QMetaEnum::keysToValue(const char *keys, bool *ok) const
             key += scope + 2;
         }
         int i;
-        for (i = count-1; i >= 0; --i)
-            if ((!scope || (stringSize(mobj, 0) == int(scope) && strncmp(qualified_key.constData(), rawStringData(mobj, 0), scope) == 0))
+        for (i = count-1; i >= 0; --i) {
+            const QByteArray className = stringData(mobj, priv(mobj->d.data)->className);
+            if ((!scope || (className.size() == int(scope) && strncmp(qualified_key.constData(), className.constData(), scope) == 0))
                  && strcmp(key, rawStringData(mobj, mobj->d.data[data + 2*i])) == 0) {
                 value |= mobj->d.data[data + 2*i + 1];
                 break;
             }
+        }
         if (i < 0) {
             if (ok != 0)
                 *ok = false;
@@ -2895,15 +2920,7 @@ bool QMetaProperty::write(QObject *object, const QVariant &value) const
             typeName = rawStringData(mobj, typeInfo & TypeNameIndexMask);
             t = QMetaType::type(typeName);
         }
-        if (t == QMetaType::UnknownType) {
-            Q_ASSERT(typeName != 0);
-            const char *vtypeName = value.typeName();
-            if (vtypeName && strcmp(typeName, vtypeName) == 0)
-                t = value.userType();
-            else
-                t = QVariant::nameToType(typeName);
-        }
-        if (t == QVariant::Invalid)
+        if (t == QMetaType::UnknownType)
             return false;
         if (t != QMetaType::QVariant && t != (uint)value.userType() && (t < QMetaType::User && !v.convert((QVariant::Type)t)))
             return false;