MetaObject: Store the QMetaType of the methods

This does the analog of 46f407126ef3e94d59254012cdc34d6a4ad2faf2 for the
methods we care about (signals, slots, Q_INVOKABLEs). In addition to the
actual QMetaType, we store an array with offsets so that we later can do
a mapping from methodIndex to metatype.

The newly added QMetaMethod::{return,parameter}MetaType methods can then
be used to retrieve the metatypes.

This does however require that all involved types are complete. This is
unfortunately not a feasible requirement. Thus, we only populate the
metatype array on a best effort basis. For any incomplete type, we store
QMetaType::Unknown. Then, when accessing the metatype, we fall back to
the old string based code base if it's Unknown.

Squashes "moc: support incomplete types" and  "Fix compile failures
after QMetaMethod change"


Fixes: QTBUG-82932
Change-Id: I6b7a587cc364b7cad0c158d6de54e8a204289ad4
Reviewed-by: Lars Knoll <lars.knoll@qt.io>

3 files changed, 64 insertions, 5 deletions

diff --git a/tests/auto/corelib/kernel/qmetamethod/tst_qmetamethod.cpp b/tests/auto/corelib/kernel/qmetamethod/tst_qmetamethod.cpp
index 4584b6ce31..8450537019 100644
--- a/tests/auto/corelib/kernel/qmetamethod/tst_qmetamethod.cpp
+++ b/tests/auto/corelib/kernel/qmetamethod/tst_qmetamethod.cpp
@@ -48,6 +48,9 @@ private slots:
     void fromSignal();
 
     void gadget();
+
+    void returnMetaType();
+    void parameterMetaType();
 };
 
 struct CustomType { };
@@ -378,10 +381,11 @@ void tst_QMetaMethod::method_data()
             << QMetaMethod::Public
             << QMetaMethod::Constructor;
 
+    // since Qt 6.0, parameter types get automatically registered
     QTest::newRow("voidSignalCustomUnregisteredType")
             << QByteArray("voidSignalCustomUnregisteredType(CustomUnregisteredType)")
             << int(QMetaType::Void) << QByteArray("void")
-            << (QList<int>() << 0)
+            << (QList<int>() << QMetaType::fromType<CustomUnregisteredType>().id())
             << (QList<QByteArray>() << QByteArray("CustomUnregisteredType"))
             << (QList<QByteArray>() << QByteArray("voidSignalCustomUnregisteredTypeArg"))
             << QMetaMethod::Public
@@ -390,7 +394,7 @@ void tst_QMetaMethod::method_data()
     QTest::newRow("voidInvokableCustomUnregisteredType")
             << QByteArray("voidInvokableCustomUnregisteredType(CustomUnregisteredType)")
             << int(QMetaType::Void) << QByteArray("void")
-            << (QList<int>() << 0)
+            << (QList<int>() << QMetaType::fromType<CustomUnregisteredType>().id())
             << (QList<QByteArray>() << QByteArray("CustomUnregisteredType"))
             << (QList<QByteArray>() << QByteArray("voidInvokableCustomUnregisteredTypeArg"))
             << QMetaMethod::Public
@@ -399,7 +403,7 @@ void tst_QMetaMethod::method_data()
     QTest::newRow("voidSlotCustomUnregisteredType")
             << QByteArray("voidSlotCustomUnregisteredType(CustomUnregisteredType)")
             << int(QMetaType::Void) << QByteArray("void")
-            << (QList<int>() << 0)
+            << (QList<int>() << QMetaType::fromType<CustomUnregisteredType>().id())
             << (QList<QByteArray>() << QByteArray("CustomUnregisteredType"))
             << (QList<QByteArray>() << QByteArray("voidSlotCustomUnregisteredTypeArg"))
             << QMetaMethod::Public
@@ -408,7 +412,7 @@ void tst_QMetaMethod::method_data()
     QTest::newRow("MethodTestObject(CustomUnregisteredType)")
             << QByteArray("MethodTestObject(CustomUnregisteredType)")
             << int(QMetaType::UnknownType) << QByteArray("")
-            << (QList<int>() << 0)
+            << (QList<int>() << QMetaType::fromType<CustomUnregisteredType>().id())
             << (QList<QByteArray>() << QByteArray("CustomUnregisteredType"))
             << (QList<QByteArray>() << QByteArray("constructorCustomUnregisteredTypeArg"))
             << QMetaMethod::Public
@@ -770,6 +774,59 @@ void tst_QMetaMethod::gadget()
     }
 }
 
+class MyTestClass : public QObject
+{
+    Q_OBJECT
+
+public:
+    MyTestClass() {};
+public Q_SLOTS:
+    MyGadget doStuff(int, float, MyGadget) {return {};}
+Q_SIGNALS:
+    QObject *mySignal();
+};
+
+void tst_QMetaMethod::returnMetaType()
+{
+    {
+        QMetaMethod mm = QMetaMethod::fromSignal(&MyTestClass::mySignal);
+        QCOMPARE(mm.returnMetaType(), QMetaType::fromType<QObject*>());
+    }
+    auto mo = MyTestClass::staticMetaObject;
+    {
+        const auto normalized = QMetaObject::normalizedSignature("doStuff(int, float, MyGadget)");
+        const int idx = mo.indexOfSlot(normalized);
+        QMetaMethod mm = mo.method(idx);
+        QVERIFY(mm.isValid());
+        QCOMPARE(mm.returnMetaType(), QMetaType::fromType<MyGadget>());
+    }
+    {
+        // access of parent class meta methods works, too
+        const auto normalized = QMetaObject::normalizedSignature("deleteLater()");
+        const int idx = mo.indexOfSlot(normalized);
+        QMetaMethod mm = mo.method(idx);
+        QVERIFY(mm.isValid());
+        QCOMPARE(mm.returnMetaType(), QMetaType::fromType<void>());
+    }
+}
+
+void tst_QMetaMethod::parameterMetaType()
+{
+    auto mo = MyTestClass::staticMetaObject;
+    const auto normalized = QMetaObject::normalizedSignature("doStuff(int, float, MyGadget)");
+    const int idx = mo.indexOfSlot(normalized);
+    QMetaMethod mm = mo.method(idx);
+    {
+        QVERIFY(!mm.parameterMetaType(-1).isValid());
+        QVERIFY(!mm.parameterMetaType(3).isValid());
+    }
+    {
+        QCOMPARE(mm.parameterMetaType(0), QMetaType::fromType<int>());
+        QCOMPARE(mm.parameterMetaType(1), QMetaType::fromType<float>());
+        QCOMPARE(mm.parameterMetaType(2), QMetaType::fromType<MyGadget>());
+    }
+}
+
 
 QTEST_MAIN(tst_QMetaMethod)
 #include "tst_qmetamethod.moc"
diff --git a/tests/auto/corelib/kernel/qmetaobjectbuilder/tst_qmetaobjectbuilder.cpp b/tests/auto/corelib/kernel/qmetaobjectbuilder/tst_qmetaobjectbuilder.cpp
index 14719f36f8..b8212ee6cf 100644
--- a/tests/auto/corelib/kernel/qmetaobjectbuilder/tst_qmetaobjectbuilder.cpp
+++ b/tests/auto/corelib/kernel/qmetaobjectbuilder/tst_qmetaobjectbuilder.cpp
@@ -1391,7 +1391,7 @@ private:
 };
 
 QMetaObject TestObject::staticMetaObject = {
-    { nullptr, nullptr, nullptr, nullptr, nullptr, nullptr }
+    { nullptr, nullptr, nullptr, nullptr, nullptr, nullptr, nullptr}
 };
 
 TestObject::TestObject(QObject *parent)
diff --git a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
index b977761995..68d218d87b 100644
--- a/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
+++ b/tests/auto/corelib/kernel/qobject/tst_qobject.cpp
@@ -5278,6 +5278,8 @@ void tst_QObject::connectForwardDeclare()
     QVERIFY(connect(&ob, &ForwardDeclareArguments::mySignal, &ob, &ForwardDeclareArguments::mySlot, Qt::QueuedConnection));
 }
 
+class ForwardDeclared {}; // complete definition for moc
+
 class NoDefaultConstructor
 {
     Q_GADGET