QMetaMethod: Add QMetaMethod::from(&MyClass:myFunction) support

Add QMetaMethod::from QMetaMethod::fromInvokable QMetaMethod：：fromSlot

Closes: https://bugreports.qt.io/browse/QTBUG-36861

Signed-off-by: Yonggang Luo <[email protected]>

Author: lygstate

src/corelib/kernel/qmetaobject.h

@@ -138,14 +138,48 @@ class Q_CORE_EXPORT QMetaMethod
     template <typename PointerToMemberFunction>
     static inline QMetaMethod fromSignal(PointerToMemberFunction signal)
     {
-        typedef QtPrivate::FunctionPointer<PointerToMemberFunction> SignalType;
-        static_assert(QtPrivate::HasQ_OBJECT_Macro<typename SignalType::Object>::Value,
-                      "No Q_OBJECT in the class with the signal");
-        return fromSignalImpl(&SignalType::Object::staticMetaObject,
-                              reinterpret_cast<void **>(&signal));
+        QMetaMethod method = from(signal);
+        if (method.methodType() == Signal)
+        {
+            return method;
+        }
+        return QMetaMethod();
+    }
+
+    template <typename PointerToMemberFunction>
+    static inline QMetaMethod fromSlot(PointerToMemberFunction slot)
+    {
+        QMetaMethod method = from(slot);
+        if (method.methodType() == Slot)
+        {
+            return method;
+        }
+        return QMetaMethod();
+    }
+
+    template <typename PointerToMemberFunction>
+    static inline QMetaMethod fromInvokable(PointerToMemberFunction invokable)
+    {
+        QMetaMethod method = from(invokable);
+        if (method.methodType() == Method)
+        {
+            return method;
+        }
+        return QMetaMethod();
+    }
+
+    template <typename PointerToMemberFunction>
+    static inline QMetaMethod from(PointerToMemberFunction func)
+    {
+        typedef QtPrivate::FunctionPointer<PointerToMemberFunction> ClassType;
+        static_assert(QtPrivate::HasQ_OBJECT_Macro<typename ClassType::Object>::Value,
+                      "No Q_OBJECT in the class with the func");
+        return fromSignalImpl(&ClassType::Object::staticMetaObject,
+                              reinterpret_cast<void **>(&func));
     }
 
 private:
+    // ### Qt 7: rename fromSignalImpl to fromImpl
     static QMetaMethod fromSignalImpl(const QMetaObject *, void **);
     static QMetaMethod fromRelativeMethodIndex(const QMetaObject *mobj, int index);
     static QMetaMethod fromRelativeConstructorIndex(const QMetaObject *mobj, int index);

src/tools/moc/generator.cpp

@@ -1157,13 +1157,13 @@ void Generator::generateStaticMetacall()
         }
 
     }
-    if (!cdef->signalList.isEmpty()) {
-        Q_ASSERT(needElse); // if there is signal, there was method.
+    if (!methodList.isEmpty()) {
+        Q_ASSERT(needElse); // there was method.
         fprintf(out, " else if (_c == QMetaObject::IndexOfMethod) {\n");
         fprintf(out, "        int *result = reinterpret_cast<int *>(_a[0]);\n");
         bool anythingUsed = false;
-        for (int methodindex = 0; methodindex < cdef->signalList.size(); ++methodindex) {
-            const FunctionDef &f = cdef->signalList.at(methodindex);
+        for (int methodindex = 0; methodindex < methodList.size(); ++methodindex) {
+            const FunctionDef &f = methodList.at(methodindex);
             if (f.wasCloned || !f.inPrivateClass.isEmpty() || f.isStatic)
                 continue;
             anythingUsed = true;