Get rid of !this and similar constructs

The C++ standard doesn't allow calling member functions
on a mull object. Fix all such places, by moving the checks
to the caller where required.

Change-Id: I10fb22acaf0324d8ffd3a6d8e19152e5d32f56bb
Reviewed-by: Simon Hausmann <simon.hausmann@digia.com>

9 files changed, 43 insertions, 30 deletions

diff --git a/src/qml/jsruntime/qv4arraydata.cpp b/src/qml/jsruntime/qv4arraydata.cpp
index 12254c6384..35bd6e5501 100644
--- a/src/qml/jsruntime/qv4arraydata.cpp
+++ b/src/qml/jsruntime/qv4arraydata.cpp
@@ -571,21 +571,21 @@ bool SparseArrayData::putArray(Object *o, uint index, Value *values, uint n)
 
 uint ArrayData::append(Object *obj, ArrayObject *otherObj, uint n)
 {
-    Q_ASSERT(!obj->arrayData()->hasAttributes());
+    Q_ASSERT(!obj->arrayData() || !obj->arrayData()->hasAttributes());
 
     if (!n)
         return obj->getLength();
 
     ArrayData *other = otherObj->arrayData();
 
-    if (other->isSparse())
+    if (other && other->isSparse())
         obj->initSparseArray();
     else
         obj->arrayCreate();
 
     uint oldSize = obj->getLength();
 
-    if (other->isSparse()) {
+    if (other && other->isSparse()) {
         SparseArrayData *os = static_cast<SparseArrayData *>(other);
         if (otherObj->hasAccessorProperty() && other->hasAttributes()) {
             Scope scope(obj->engine());
diff --git a/src/qml/jsruntime/qv4arraydata_p.h b/src/qml/jsruntime/qv4arraydata_p.h
index c2deb3e385..b69d200665 100644
--- a/src/qml/jsruntime/qv4arraydata_p.h
+++ b/src/qml/jsruntime/qv4arraydata_p.h
@@ -113,14 +113,14 @@ struct Q_QML_EXPORT ArrayData : public Managed
     Value *arrayData() { return &d()->arrayData[0]; }
 
     const ArrayVTable *vtable() const { return reinterpret_cast<const ArrayVTable *>(internalClass()->vtable); }
-    bool isSparse() const { return this && type() == Sparse; }
+    bool isSparse() const { return type() == Sparse; }
 
     uint length() const {
         return vtable()->length(this);
     }
 
     bool hasAttributes() const {
-        return this && attrs();
+        return attrs();
     }
     PropertyAttributes attributes(int i) const {
         Q_ASSERT(this);
diff --git a/src/qml/jsruntime/qv4identifier_p.h b/src/qml/jsruntime/qv4identifier_p.h
index 9ca6714b90..afed5c646f 100644
--- a/src/qml/jsruntime/qv4identifier_p.h
+++ b/src/qml/jsruntime/qv4identifier_p.h
@@ -56,9 +56,9 @@ struct IdentifierHashEntry {
         int value;
         void *pointer;
     };
-    int get(int *) const { return this ? value : -1; }
-    bool get(bool *) const { return this != 0; }
-    void *get(void **) const { return this ? pointer : 0; }
+    static int get(const IdentifierHashEntry *This, int *) { return This ? This->value : -1; }
+    static bool get(const IdentifierHashEntry *This, bool *) { return This != 0; }
+    static void *get(const IdentifierHashEntry *This, void **) { return This ? This->pointer : 0; }
 };
 
 struct IdentifierHashData
@@ -181,13 +181,13 @@ void IdentifierHash<T>::add(const QString &str, const T &value)
 template<typename T>
 inline T IdentifierHash<T>::value(const QString &str) const
 {
-    return lookup(str)->get((T*)0);
+    return IdentifierHashEntry::get(lookup(str), (T*)0);
 }
 
 template<typename T>
 inline T IdentifierHash<T>::value(String *str) const
 {
-    return lookup(str)->get((T*)0);
+    return IdentifierHashEntry::get(lookup(str), (T*)0);
 }
 
 
@@ -197,7 +197,7 @@ QString IdentifierHash<T>::findId(T value) const
     IdentifierHashEntry *e = d->entries;
     IdentifierHashEntry *end = e + d->alloc;
     while (e < end) {
-        if (e->identifier && e->get((T*)0) == value)
+        if (e->identifier && IdentifierHashEntry::get(e, (T*)0) == value)
             return e->identifier->string;
         ++e;
     }
diff --git a/src/qml/jsruntime/qv4managed_p.h b/src/qml/jsruntime/qv4managed_p.h
index ce0ee973e8..e679017b7e 100644
--- a/src/qml/jsruntime/qv4managed_p.h
+++ b/src/qml/jsruntime/qv4managed_p.h
@@ -269,9 +269,7 @@ public:
 
     template <typename T>
     T *as() {
-        // ### FIXME:
-        if (!this || !internalClass())
-            return 0;
+        Q_ASSERT(internalClass());
 #if !defined(QT_NO_QOBJECT_CHECK)
         static_cast<T *>(this)->qt_check_for_QMANAGED_macro(static_cast<T *>(this));
 #endif
@@ -285,9 +283,7 @@ public:
     }
     template <typename T>
     const T *as() const {
-        // ### FIXME:
-        if (!this)
-            return 0;
+        Q_ASSERT(internalClass());
 #if !defined(QT_NO_QOBJECT_CHECK)
         static_cast<T *>(this)->qt_check_for_QMANAGED_macro(static_cast<T *>(const_cast<Managed *>(this)));
 #endif
@@ -362,23 +358,23 @@ inline Managed *value_cast(const Value &v) {
 template<typename T>
 inline T *managed_cast(Managed *m)
 {
-    return m->as<T>();
+    return m ? m->as<T>() : 0;
 }
 
 template<>
 inline String *managed_cast(Managed *m)
 {
-    return m->asString();
+    return m ? m->asString() : 0;
 }
 template<>
 inline Object *managed_cast(Managed *m)
 {
-    return m->asObject();
+    return m ? m->asObject() : 0;
 }
 template<>
 inline FunctionObject *managed_cast(Managed *m)
 {
-    return m->asFunctionObject();
+    return m ? m->asFunctionObject() : 0;
 }
 
 }
diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index 32379f7f1e..f2c30e618f 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -650,9 +650,13 @@ void QObjectWrapper::setProperty(ExecutionContext *ctx, int propertyIndex, const
 
 bool QObjectWrapper::isEqualTo(Managed *a, Managed *b)
 {
-    QV4::QObjectWrapper *qobjectWrapper = a->as<QV4::QObjectWrapper>();
-    if (QV4::QmlTypeWrapper *qmlTypeWrapper = b->asObject()->as<QV4::QmlTypeWrapper>())
-        return qmlTypeWrapper->toVariant().value<QObject*>() == qobjectWrapper->object();
+    Q_ASSERT(a->as<QV4::QObjectWrapper>());
+    QV4::QObjectWrapper *qobjectWrapper = static_cast<QV4::QObjectWrapper *>(a);
+    QV4::Object *o = b->asObject();
+    if (o) {
+        if (QV4::QmlTypeWrapper *qmlTypeWrapper = o->as<QV4::QmlTypeWrapper>())
+            return qmlTypeWrapper->toVariant().value<QObject*>() == qobjectWrapper->object();
+    }
 
     return false;
 }
diff --git a/src/qml/jsruntime/qv4runtime.cpp b/src/qml/jsruntime/qv4runtime.cpp
index 048ff935bf..f72f25bd58 100644
--- a/src/qml/jsruntime/qv4runtime.cpp
+++ b/src/qml/jsruntime/qv4runtime.cpp
@@ -1276,7 +1276,8 @@ ReturnedValue Runtime::regexpLiteral(ExecutionContext *ctx, int id)
 
 ReturnedValue Runtime::getQmlIdArray(NoThrowContext *ctx)
 {
-    return ctx->engine()->qmlContextObject()->getPointer()->as<QmlContextWrapper>()->idObjectsArray();
+    Q_ASSERT(ctx->engine()->qmlContextObject()->getPointer()->as<QmlContextWrapper>());
+    return static_cast<QmlContextWrapper *>(ctx->engine()->qmlContextObject()->getPointer())->idObjectsArray();
 }
 
 ReturnedValue Runtime::getQmlContextObject(NoThrowContext *ctx)
@@ -1290,7 +1291,7 @@ ReturnedValue Runtime::getQmlContextObject(NoThrowContext *ctx)
 ReturnedValue Runtime::getQmlScopeObject(NoThrowContext *ctx)
 {
     Scope scope(ctx);
-    QV4::Scoped<QmlContextWrapper> c(scope, ctx->engine()->qmlContextObject()->getPointer()->as<QmlContextWrapper>());
+    QV4::Scoped<QmlContextWrapper> c(scope, ctx->engine()->qmlContextObject(), Scoped<QmlContextWrapper>::Cast);
     return QObjectWrapper::wrap(ctx->d()->engine, c->getScopeObject());
 }
 
@@ -1308,7 +1309,7 @@ ReturnedValue Runtime::getQmlQObjectProperty(ExecutionContext *ctx, const ValueR
 QV4::ReturnedValue Runtime::getQmlAttachedProperty(ExecutionContext *ctx, int attachedPropertiesId, int propertyIndex)
 {
     Scope scope(ctx);
-    QV4::Scoped<QmlContextWrapper> c(scope, ctx->engine()->qmlContextObject()->getPointer()->as<QmlContextWrapper>());
+    QV4::Scoped<QmlContextWrapper> c(scope, ctx->engine()->qmlContextObject(), Scoped<QmlContextWrapper>::Cast);
     QObject *scopeObject = c->getScopeObject();
     QObject *attachedObject = qmlAttachedPropertiesObjectById(attachedPropertiesId, scopeObject);
 
@@ -1349,7 +1350,7 @@ ReturnedValue Runtime::getQmlImportedScripts(NoThrowContext *ctx)
 
 QV4::ReturnedValue Runtime::getQmlSingleton(QV4::NoThrowContext *ctx, String *name)
 {
-    return ctx->engine()->qmlContextObject()->getPointer()->as<QmlContextWrapper>()->qmlSingletonWrapper(ctx->engine()->v8Engine, name);
+    return static_cast<QmlContextWrapper *>(ctx->engine()->qmlContextObject()->getPointer())->qmlSingletonWrapper(ctx->engine()->v8Engine, name);
 }
 
 void Runtime::convertThisToObject(ExecutionContext *ctx)
diff --git a/src/qml/jsruntime/qv4scopedvalue_p.h b/src/qml/jsruntime/qv4scopedvalue_p.h
index 9e9a6e60c9..b1b4d5da8d 100644
--- a/src/qml/jsruntime/qv4scopedvalue_p.h
+++ b/src/qml/jsruntime/qv4scopedvalue_p.h
@@ -288,6 +288,16 @@ struct Scoped
 #endif
     }
 
+    template<typename X>
+    Scoped(const Scope &scope, Returned<X> *x, _Cast)
+    {
+        ptr = scope.engine->jsStackTop++;
+        setPointer(managed_cast<T>(x->getPointer()));
+#ifndef QT_NO_DEBUG
+        ++scope.size;
+#endif
+    }
+
     Scoped(const Scope &scope, const ReturnedValue &v)
     {
         ptr = scope.engine->jsStackTop++;
diff --git a/src/qml/jsruntime/qv4sequenceobject.cpp b/src/qml/jsruntime/qv4sequenceobject.cpp
index a45f4cabc5..7a0a643a7e 100644
--- a/src/qml/jsruntime/qv4sequenceobject.cpp
+++ b/src/qml/jsruntime/qv4sequenceobject.cpp
@@ -331,6 +331,8 @@ public:
 
     bool containerIsEqualTo(Managed *other)
     {
+        if (!other)
+            return false;
         QQmlSequence<Container> *otherSequence = other->as<QQmlSequence<Container> >();
         if (!otherSequence)
             return false;
diff --git a/src/qml/jsruntime/qv4variantobject.cpp b/src/qml/jsruntime/qv4variantobject.cpp
index 68b08fb3ca..3cde96992e 100644
--- a/src/qml/jsruntime/qv4variantobject.cpp
+++ b/src/qml/jsruntime/qv4variantobject.cpp
@@ -92,8 +92,8 @@ void VariantObject::destroy(Managed *that)
 
 bool VariantObject::isEqualTo(Managed *m, Managed *other)
 {
-    QV4::VariantObject *lv = m->as<QV4::VariantObject>();
-    assert(lv);
+    Q_ASSERT(m->as<QV4::VariantObject>());
+    QV4::VariantObject *lv = static_cast<QV4::VariantObject *>(m);
 
     if (QV4::VariantObject *rv = other->as<QV4::VariantObject>())
         return lv->d()->data == rv->d()->data;