QMetaContainer: Consistently coerce types

The high-level iterable interfaces should coerce the types of most
QVariants passed to the expected ones. To do this, move the type
coercion code into qvariant.{h|cpp} so that it is available to the
QVariantRef specializations.

The exception are variants passed to the find() functions of associative
iterables. Here, we should not coerce values we cannot convert to the
default-constructed keys. Instead we return end() in such cases.

Fixes: QTBUG-87687
Change-Id: I0bd4e5c4e4e270dd3bf36cb3fb115794828077f2
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

1 files changed, 12 insertions, 0 deletions

diff --git a/src/corelib/kernel/qvariant.h b/src/corelib/kernel/qvariant.h
index 40d3d5c3b1..aa74aaa18f 100644
--- a/src/corelib/kernel/qvariant.h
+++ b/src/corelib/kernel/qvariant.h
@@ -605,6 +605,18 @@ template<> inline QVariant qvariant_cast<QVariant>(const QVariant &v)
 Q_CORE_EXPORT QDebug operator<<(QDebug, const QVariant::Type);
 #endif
 
+namespace QtPrivate {
+class Q_CORE_EXPORT QVariantTypeCoercer
+{
+public:
+    const void *convert(const QVariant &value, const QMetaType &type);
+    const void *coerce(const QVariant &value, const QMetaType &type);
+
+private:
+    QVariant converted;
+};
+}
+
 template<typename Pointer>
 class QVariantRef
 {