From d61a15d043e70d79f5b27f04e85595a36014a734 Mon Sep 17 00:00:00 2001
From: Phil Thompson <phil@riverbankcomputing.com>
Date: Wed, 23 Oct 2024 16:28:27 +0100
Subject: [PATCH] Fix QFlag properties built by QMetaObjectBuilder

When Q_PROPERTY is used to define a property with type (for example)
Qt::Alignment the name of the type stored in the meta-object is
"Qt::Alignment".

When QMetaObjectBuilder.addProperty() is used it will instead use the
name of the meta-type (ie. "QFlags<Qt::AlignmentFlag>") which it has
obtained from QMetaType::fromName("Qt::Alignment").name().

In the QMetaProperty ctor it tries to resolve the QMetaEnum for the
property and uses the internal parse_scope() to extract the scope and
qualified key from the name. However it does not handle template names
and so fails with dynamically created properties.

This change to parse_scope() removes the "QFlags<>" so that the
template type can then be parsed.

Another solution would be for addProperty() to always use the type name
it was given rather than use QMetaType::fromName(). That has the
advantage that the layout of the dynamic meta-object would match that
generated by moc.

Change-Id: Iac9e2db2f134029709158b4e500286922396501d
Reviewed-by: Thiago Macieira <thiago.macieira@intel.com>
(cherry picked from commit 5624060865e3ccd3c487f10355cb740b7322f93c)
Reviewed-by: Qt Cherry-pick Bot <cherrypick_bot@qt-project.org>
---
 src/corelib/kernel/qmetaobject.cpp                  |  2 ++
 .../kernel/qmetaproperty/tst_qmetaproperty.cpp      | 13 +++++++++++++
 2 files changed, 15 insertions(+)

diff --git a/src/corelib/kernel/qmetaobject.cpp b/src/corelib/kernel/qmetaobject.cpp
index 3d0cfb4b33d..f375a7b8a96 100644
--- a/src/corelib/kernel/qmetaobject.cpp
+++ b/src/corelib/kernel/qmetaobject.cpp
@@ -163,6 +163,8 @@ static auto parse_scope(QByteArrayView qualifiedKey) noexcept
         std::optional<QByteArrayView> scope;
         QByteArrayView key;
     };
+    if (qualifiedKey.startsWith("QFlags<") && qualifiedKey.endsWith('>'))
+        qualifiedKey.slice(7, qualifiedKey.length() - 8);
     const auto scopePos = qualifiedKey.lastIndexOf("::"_L1);
     if (scopePos < 0)
         return R{std::nullopt, qualifiedKey};
diff --git a/tests/auto/corelib/kernel/qmetaproperty/tst_qmetaproperty.cpp b/tests/auto/corelib/kernel/qmetaproperty/tst_qmetaproperty.cpp
index 3bf6211a539..5b3792bcb8d 100644
--- a/tests/auto/corelib/kernel/qmetaproperty/tst_qmetaproperty.cpp
+++ b/tests/auto/corelib/kernel/qmetaproperty/tst_qmetaproperty.cpp
@@ -41,6 +41,7 @@ class tst_QMetaProperty : public Base
     Q_PROPERTY(QMap<int, int> map MEMBER map)
     Q_PROPERTY(CustomType custom MEMBER custom)
     Q_PROPERTY(int propWithInheritedSig READ propWithInheritedSig NOTIFY baseSignal)
+    Q_PROPERTY(QFlags<Qt::AlignmentFlag> qflags_value MEMBER qflags_value)
 
 private slots:
     void hasStdCppSet();
@@ -52,6 +53,7 @@ private slots:
     void conversion();
     void enumsFlags();
     void notifySignalIndex();
+    void qflags();
 
 public:
     enum EnumType { EnumType1 };
@@ -71,6 +73,7 @@ public:
     QString value7;
     QMap<int, int> map;
     CustomType custom;
+    QFlags<Qt::AlignmentFlag> qflags_value;
 };
 
 void tst_QMetaProperty::hasStdCppSet()
@@ -112,6 +115,16 @@ void tst_QMetaProperty::isFinal()
     QVERIFY(!prop.isFinal());
 }
 
+void tst_QMetaProperty::qflags()
+{
+    const QMetaObject *mo = metaObject();
+
+    QMetaProperty prop = mo->property(mo->indexOfProperty("qflags_value"));
+    QVERIFY(prop.isEnumType());
+    QVERIFY(prop.isFlagType());
+}
+
+
 class MyGadget {
     Q_GADGET
     Q_PROPERTY(QString value READ getValue WRITE setValue RESET resetValue)