Make QML composite types inherit enums

Problem: in Qt Quick Controls 2, enums declared in the abstract
C++ base types were not accessible with the concrete QML type name,
but had to be referenced using the base type name:

    Slider {
        snapMode: AbstractSlider.SnapOnRelease
    }

Solution: this change resolves the C++ base type and creates the
missing link between the composite type and its base type's meta-
object. This allows referencing enums using the concrete/composite
QML type name:

    Slider {
        snapMode: Slider.SnapOnRelease
    }

Change-Id: Icefdec91b012b12728367fd54b4d16796233ee12
Task-number: QTBUG-43582
Reviewed-by: Simon Hausmann <simon.hausmann@theqtcompany.com>

9 files changed, 48 insertions, 15 deletions

diff --git a/src/qml/compiler/qqmlirbuilder.cpp b/src/qml/compiler/qqmlirbuilder.cpp
index 4b1e3601dc..7b0d4240c4 100644
--- a/src/qml/compiler/qqmlirbuilder.cpp
+++ b/src/qml/compiler/qqmlirbuilder.cpp
@@ -1590,7 +1590,7 @@ static QV4::IR::Type resolveQmlType(QQmlEnginePrivate *qmlEngine, QV4::IR::Membe
 
     if (member->name->constData()->isUpper()) {
         bool ok = false;
-        int value = type->enumValue(*member->name, &ok);
+        int value = type->enumValue(qmlEngine, *member->name, &ok);
         if (ok) {
             member->setEnumValue(value);
             resolver->clear();
diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index 7f62446c22..e36ba76326 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -1163,8 +1163,6 @@ bool QQmlEnumTypeResolver::tryQualifiedEnumAssignment(const QmlIR::Object *obj,
 
     if (!type && typeName != QLatin1String("Qt"))
         return true;
-    if (type && type->isComposite()) //No enums on composite (or composite singleton) types
-        return true;
 
     int value = 0;
     bool ok = false;
@@ -1182,7 +1180,7 @@ bool QQmlEnumTypeResolver::tryQualifiedEnumAssignment(const QmlIR::Object *obj,
     } else {
         // Otherwise we have to search the whole type
         if (type) {
-            value = type->enumValue(QHashedStringRef(enumValue), &ok);
+            value = type->enumValue(compiler->enginePrivate(), QHashedStringRef(enumValue), &ok);
         } else {
             QByteArray enumName = enumValue.toUtf8();
             const QMetaObject *metaObject = StaticQtMetaObject::get();
@@ -1210,7 +1208,9 @@ int QQmlEnumTypeResolver::evaluateEnum(const QString &scope, const QByteArray &e
     if (scope != QLatin1String("Qt")) {
         QQmlType *type = 0;
         imports->resolveType(scope, &type, 0, 0, 0);
-        return type ? type->enumValue(QHashedCStringRef(enumValue.constData(), enumValue.length()), ok) : -1;
+        if (!type)
+            return -1;
+        return type ? type->enumValue(compiler->enginePrivate(), QHashedCStringRef(enumValue.constData(), enumValue.length()), ok) : -1;
     }
 
     const QMetaObject *mo = StaticQtMetaObject::get();
@@ -1988,9 +1988,11 @@ bool QQmlPropertyValidator::validateObject(int objectIndex, const QV4::CompiledD
     if (customParser && !customBindings.isEmpty()) {
         customParser->clearErrors();
         customParser->validator = this;
+        customParser->engine = enginePrivate;
         customParser->imports = compiler->imports();
         customParser->verifyBindings(qmlUnit, customBindings);
         customParser->validator = 0;
+        customParser->engine = 0;
         customParser->imports = (QQmlImports*)0;
         customParserBindingsPerObject->insert(objectIndex, customParserBindings);
         const QList<QQmlError> parserErrors = customParser->errors();
diff --git a/src/qml/compiler/qqmltypecompiler_p.h b/src/qml/compiler/qqmltypecompiler_p.h
index cbc68280b7..09ef7aad67 100644
--- a/src/qml/compiler/qqmltypecompiler_p.h
+++ b/src/qml/compiler/qqmltypecompiler_p.h
@@ -273,6 +273,7 @@ public:
     bool validate();
 
     const QQmlImports &imports() const;
+    QQmlEnginePrivate *engine() const { return enginePrivate; }
 
 private:
     bool validateObject(int objectIndex, const QV4::CompiledData::Binding *instantiatingBinding, bool populatingValueTypeGroupProperty = false) const;
diff --git a/src/qml/qml/qqmlcustomparser.cpp b/src/qml/qml/qqmlcustomparser.cpp
index ec88ee015a..517f8d42ed 100644
--- a/src/qml/qml/qqmlcustomparser.cpp
+++ b/src/qml/qml/qqmlcustomparser.cpp
@@ -141,7 +141,7 @@ int QQmlCustomParser::evaluateEnum(const QByteArray& script, bool *ok) const
                 type = result.type;
         }
 
-        return type ? type->enumValue(QHashedCStringRef(enumValue.constData(), enumValue.length()), ok) : -1;
+        return type ? type->enumValue(engine, QHashedCStringRef(enumValue.constData(), enumValue.length()), ok) : -1;
     }
 
     const QMetaObject *mo = StaticQtMetaObject::get();
diff --git a/src/qml/qml/qqmlcustomparser_p.h b/src/qml/qml/qqmlcustomparser_p.h
index dd461ba299..8bdc73fab1 100644
--- a/src/qml/qml/qqmlcustomparser_p.h
+++ b/src/qml/qml/qqmlcustomparser_p.h
@@ -56,6 +56,7 @@ QT_BEGIN_NAMESPACE
 
 class QQmlCompiledData;
 class QQmlPropertyValidator;
+class QQmlEnginePrivate;
 
 class Q_QML_PRIVATE_EXPORT QQmlCustomParser
 {
@@ -67,8 +68,8 @@ public:
     };
     Q_DECLARE_FLAGS(Flags, Flag)
 
-    QQmlCustomParser() : validator(0), m_flags(NoFlag) {}
-    QQmlCustomParser(Flags f) : validator(0), m_flags(f) {}
+    QQmlCustomParser() : engine(0), validator(0), m_flags(NoFlag) {}
+    QQmlCustomParser(Flags f) : engine(0), validator(0), m_flags(f) {}
     virtual ~QQmlCustomParser() {}
 
     void clearErrors();
@@ -92,6 +93,7 @@ protected:
 
 private:
     QList<QQmlError> exceptions;
+    QQmlEnginePrivate *engine;
     const QQmlPropertyValidator *validator;
     Flags m_flags;
     QBiPointer<const QQmlImports, QQmlTypeNameCache> imports;
diff --git a/src/qml/qml/qqmlmetatype.cpp b/src/qml/qml/qqmlmetatype.cpp
index f0debb8e59..b173bc8bec 100644
--- a/src/qml/qml/qqmlmetatype.cpp
+++ b/src/qml/qml/qqmlmetatype.cpp
@@ -38,6 +38,7 @@
 #include <private/qqmlcustomparser_p.h>
 #include <private/qhashedstring_p.h>
 #include <private/qqmlimport_p.h>
+#include <private/qqmlcompiler_p.h>
 
 #include <QtCore/qdebug.h>
 #include <QtCore/qstringlist.h>
@@ -473,6 +474,23 @@ QQmlType *QQmlType::superType() const
     return d->superType;
 }
 
+int QQmlType::resolveCompositeEnumValue(QQmlEnginePrivate *engine, const QString &name, bool *ok) const
+{
+    Q_ASSERT(isComposite());
+    *ok = false;
+    if (!engine)
+        return -1;
+    QQmlTypeData *td = engine->typeLoader.getType(sourceUrl());
+    if (!td || !td->isComplete())
+        return -1;
+    QQmlCompiledData *cd = td->compiledData();
+    const QMetaObject *mo = cd->rootPropertyCache->firstCppMetaObject();
+    QQmlType *type = QQmlMetaType::qmlType(mo);
+    if (!type)
+        return -1;
+    return type->enumValue(engine, name, ok);
+}
+
 static void clone(QMetaObjectBuilder &builder, const QMetaObject *mo,
                   const QMetaObject *ignoreStart, const QMetaObject *ignoreEnd)
 {
@@ -907,9 +925,11 @@ QUrl QQmlType::sourceUrl() const
         return QUrl();
 }
 
-int QQmlType::enumValue(const QHashedStringRef &name, bool *ok) const
+int QQmlType::enumValue(QQmlEnginePrivate *engine, const QHashedStringRef &name, bool *ok) const
 {
     Q_ASSERT(ok);
+    if (isComposite())
+        return resolveCompositeEnumValue(engine, name.toString(), ok);
     *ok = true;
 
     d->initEnums();
@@ -922,9 +942,11 @@ int QQmlType::enumValue(const QHashedStringRef &name, bool *ok) const
     return -1;
 }
 
-int QQmlType::enumValue(const QHashedCStringRef &name, bool *ok) const
+int QQmlType::enumValue(QQmlEnginePrivate *engine, const QHashedCStringRef &name, bool *ok) const
 {
     Q_ASSERT(ok);
+    if (isComposite())
+        return resolveCompositeEnumValue(engine, name.toUtf16(), ok);
     *ok = true;
 
     d->initEnums();
@@ -937,9 +959,11 @@ int QQmlType::enumValue(const QHashedCStringRef &name, bool *ok) const
     return -1;
 }
 
-int QQmlType::enumValue(const QV4::String *name, bool *ok) const
+int QQmlType::enumValue(QQmlEnginePrivate *engine, const QV4::String *name, bool *ok) const
 {
     Q_ASSERT(ok);
+    if (isComposite())
+        return resolveCompositeEnumValue(engine, name->toQString(), ok);
     *ok = true;
 
     d->initEnums();
diff --git a/src/qml/qml/qqmlmetatype_p.h b/src/qml/qml/qqmlmetatype_p.h
index 61a6567f1d..08f19bcf09 100644
--- a/src/qml/qml/qqmlmetatype_p.h
+++ b/src/qml/qml/qqmlmetatype_p.h
@@ -57,6 +57,7 @@ QT_BEGIN_NAMESPACE
 
 class QQmlType;
 class QQmlEngine;
+class QQmlEnginePrivate;
 class QQmlCustomParser;
 class QQmlTypePrivate;
 class QQmlTypeModule;
@@ -204,11 +205,12 @@ public:
 
     QUrl sourceUrl() const;
 
-    int enumValue(const QHashedStringRef &, bool *ok) const;
-    int enumValue(const QHashedCStringRef &, bool *ok) const;
-    int enumValue(const QV4::String *, bool *ok) const;
+    int enumValue(QQmlEnginePrivate *engine, const QHashedStringRef &, bool *ok) const;
+    int enumValue(QQmlEnginePrivate *engine, const QHashedCStringRef &, bool *ok) const;
+    int enumValue(QQmlEnginePrivate *engine, const QV4::String *, bool *ok) const;
 private:
     QQmlType *superType() const;
+    int resolveCompositeEnumValue(QQmlEnginePrivate *engine, const QString &name, bool *ok) const;
     friend class QQmlTypePrivate;
     friend struct QQmlMetaTypeData;
 
diff --git a/src/qml/qml/qqmlobjectcreator.cpp b/src/qml/qml/qqmlobjectcreator.cpp
index f371a369a1..171fa048ce 100644
--- a/src/qml/qml/qqmlobjectcreator.cpp
+++ b/src/qml/qml/qqmlobjectcreator.cpp
@@ -1101,6 +1101,7 @@ QObject *QQmlObjectCreator::createInstance(int index, QObject *parent, bool isCo
     if (customParser) {
         QHash<int, QBitArray>::ConstIterator customParserBindings = compiledData->customParserBindings.constFind(index);
         if (customParserBindings != compiledData->customParserBindings.constEnd()) {
+            customParser->engine = QQmlEnginePrivate::get(engine);
             customParser->imports = compiledData->importCache;
 
             QList<const QV4::CompiledData::Binding *> bindings;
@@ -1110,6 +1111,7 @@ QObject *QQmlObjectCreator::createInstance(int index, QObject *parent, bool isCo
                     bindings << obj->bindingTable() + i;
             customParser->applyBindings(instance, compiledData, bindings);
 
+            customParser->engine = 0;
             customParser->imports = (QQmlTypeNameCache*)0;
             bindingsToSkip = *customParserBindings;
         }
diff --git a/src/qml/qml/qqmltypewrapper.cpp b/src/qml/qml/qqmltypewrapper.cpp
index 1d72b2da0d..1145f1b64f 100644
--- a/src/qml/qml/qqmltypewrapper.cpp
+++ b/src/qml/qml/qqmltypewrapper.cpp
@@ -182,7 +182,7 @@ ReturnedValue QmlTypeWrapper::get(const Managed *m, String *name, bool *hasPrope
 
             if (name->startsWithUpper()) {
                 bool ok = false;
-                int value = type->enumValue(name, &ok);
+                int value = type->enumValue(QQmlEnginePrivate::get(v4->qmlEngine()), name, &ok);
                 if (ok)
                     return QV4::Primitive::fromInt32(value).asReturnedValue();