[new compiler] Fix auto component creation with composite types

A binding like this

    property Component foo: SomeComposite {}

should not do an implicit component insertion if SomeComposite is actually
a component. The property assignment is compatible and can proceed normally.
Fixes tst_qquickcanvasitem, but added a separate unit test for this case.

Change-Id: I7221eebd38dba3f2a82b59341739b9b67211e352
Reviewed-by: Lars Knoll <lars.knoll@digia.com>

1 files changed, 7 insertions, 3 deletions

diff --git a/src/qml/compiler/qqmltypecompiler.cpp b/src/qml/compiler/qqmltypecompiler.cpp
index fd3d8a92e3..f6eb4bc40e 100644
--- a/src/qml/compiler/qqmltypecompiler.cpp
+++ b/src/qml/compiler/qqmltypecompiler.cpp
@@ -1275,9 +1275,13 @@ void QQmlComponentAndAliasResolver::findAndRegisterImplicitComponents(const QtQm
         const QtQml::QmlObject *targetObject = qmlObjects->at(binding->value.objectIndex);
         QQmlCompiledData::TypeReference *tr = resolvedTypes->value(targetObject->inheritedTypeNameIndex);
         Q_ASSERT(tr);
-        QQmlType *targetType = tr->type;
-        if (targetType && targetType->metaObject() == &QQmlComponent::staticMetaObject)
-            continue;
+        if (QQmlType *targetType = tr->type) {
+            if (targetType->metaObject() == &QQmlComponent::staticMetaObject)
+                continue;
+        } else if (tr->component) {
+            if (tr->component->rootPropertyCache->firstCppMetaObject() == &QQmlComponent::staticMetaObject)
+                continue;
+        }
 
         QQmlPropertyData *pd = 0;
         if (binding->propertyNameIndex != 0) {