Add support for exposing public QProperty members in the meta-object system

At the moment this makes the type as well as the setter/getter available
through the meta-call as well as the ability to register observers and
bindings. Only QProperty members that are annotated with
Q_PROPERTY(type name) are made public through the meta-object.

Change-Id: I16b98fd318122c722b85ce61e39975284e0c2404
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

2 files changed, 120 insertions, 3 deletions

diff --git a/tests/auto/tools/moc/allmocs_baseline_in.json b/tests/auto/tools/moc/allmocs_baseline_in.json
index 9cc06dc7bc..77647329c9 100644
--- a/tests/auto/tools/moc/allmocs_baseline_in.json
+++ b/tests/auto/tools/moc/allmocs_baseline_in.json
@@ -1046,6 +1046,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "prop1",
                         "read": "getProp1",
                         "required": false,
@@ -1059,6 +1060,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "prop2",
                         "read": "getProp2",
                         "required": false,
@@ -1072,6 +1074,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "prop3",
                         "read": "getProp3",
                         "required": false,
@@ -1184,6 +1187,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "flags",
                         "read": "flags",
                         "required": false,
@@ -1210,6 +1214,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "flags",
                         "read": "flags",
                         "required": false,
@@ -1223,6 +1228,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "flagsList",
                         "read": "flagsList",
                         "required": false,
@@ -1747,6 +1753,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "blah",
                         "read": "blah",
                         "required": false,
@@ -1799,6 +1806,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "blah",
                         "read": "blah",
                         "required": false,
@@ -1974,6 +1982,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "gadgetPoperty",
                         "read": "gadgetPoperty",
                         "required": false,
@@ -1986,6 +1995,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "objectPoperty",
                         "read": "objectPoperty",
                         "required": false,
@@ -2011,6 +2021,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "nestedGadgetPoperty",
                         "read": "nestedGadgetPoperty",
                         "required": false,
@@ -2036,6 +2047,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "nestedObjectPoperty",
                         "read": "nestedObjectPoperty",
                         "required": false,
@@ -2169,6 +2181,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "gadgetPoperty",
                         "read": "gadgetPoperty",
                         "required": false,
@@ -2181,6 +2194,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "objectPoperty",
                         "read": "objectPoperty",
                         "required": false,
@@ -2206,6 +2220,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "nestedGadgetPoperty",
                         "read": "nestedGadgetPoperty",
                         "required": false,
@@ -2231,6 +2246,7 @@
                         "constant": false,
                         "designable": true,
                         "final": false,
+                        "isQProperty": false,
                         "name": "nestedObjectPoperty",
                         "read": "nestedObjectPoperty",
                         "required": false,
diff --git a/tests/auto/tools/moc/tst_moc.cpp b/tests/auto/tools/moc/tst_moc.cpp
index 31fe68a64e..221e741647 100644
--- a/tests/auto/tools/moc/tst_moc.cpp
+++ b/tests/auto/tools/moc/tst_moc.cpp
@@ -723,6 +723,9 @@ private slots:
     void mocJsonOutput();
     void mocInclude();
     void requiredProperties();
+    void qpropertyMembers();
+    void observerMetaCall();
+    void setQPRopertyBinding();
 
 signals:
     void sigWithUnsignedArg(unsigned foo);
@@ -1603,7 +1606,7 @@ void tst_Moc::warnOnPropertyWithoutREAD()
     QVERIFY(!mocOut.isEmpty());
     QString mocWarning = QString::fromLocal8Bit(proc.readAllStandardError());
     QCOMPARE(mocWarning, header +
-                QString(":36: Warning: Property declaration foo has no READ accessor function or associated MEMBER variable. The property will be invalid.\n"));
+                QString(":36: Warning: Property declaration foo has neither an associated QProperty<> member, nor a READ accessor function nor an associated MEMBER variable. The property will be invalid.\n"));
 #else
     QSKIP("Only tested on linux/gcc");
 #endif
@@ -2087,7 +2090,7 @@ void tst_Moc::warnings_data()
         << QStringList()
         << 0
         << QString("IGNORE_ALL_STDOUT")
-        << QString("standard input:1: Warning: Property declaration x has no READ accessor function or associated MEMBER variable. The property will be invalid.");
+        << QString("standard input:1: Warning: Property declaration x has neither an associated QProperty<> member, nor a READ accessor function nor an associated MEMBER variable. The property will be invalid.");
 
     // This should output a warning
     QTest::newRow("Duplicate property warning")
@@ -2103,7 +2106,7 @@ void tst_Moc::warnings_data()
         << (QStringList() << "-nn")
         << 0
         << QString("IGNORE_ALL_STDOUT")
-        << QString("standard input:1: Warning: Property declaration x has no READ accessor function or associated MEMBER variable. The property will be invalid.");
+        << QString("standard input:1: Warning: Property declaration x has neither an associated QProperty<> member, nor a READ accessor function nor an associated MEMBER variable. The property will be invalid.");
 
     // Passing "-nw" should suppress the warning
     QTest::newRow("Invalid property warning with -nw")
@@ -4100,6 +4103,104 @@ void tst_Moc::requiredProperties()
     QVERIFY(!notRequired.isRequired());
 }
 
+class ClassWithQPropertyMembers : public QObject
+{
+    Q_OBJECT
+    Q_PROPERTY(int publicProperty)
+    Q_PROPERTY(int privateExposedProperty)
+public:
+
+    QProperty<int> publicProperty;
+    QProperty<int> notExposed;
+
+protected:
+    QProperty<int> protectedProperty;
+
+private:
+    QProperty<int> privateProperty;
+    QProperty<int> privateExposedProperty;
+};
+
+void tst_Moc::qpropertyMembers()
+{
+    const auto metaObject = &ClassWithQPropertyMembers::staticMetaObject;
+
+    QCOMPARE(metaObject->propertyCount() - metaObject->superClass()->propertyCount(), 2);
+
+    QCOMPARE(metaObject->indexOfProperty("notExposed"), -1);
+
+    QMetaProperty prop = metaObject->property(metaObject->indexOfProperty("publicProperty"));
+    QVERIFY(prop.isValid());
+
+    QVERIFY(metaObject->property(metaObject->indexOfProperty("privateExposedProperty")).isValid());
+
+    ClassWithQPropertyMembers instance;
+
+    prop.write(&instance, 42);
+    QCOMPARE(instance.publicProperty.value(), 42);
+
+    instance.publicProperty.setValue(100);
+    QCOMPARE(prop.read(&instance).toInt(), 100);
+
+    QCOMPARE(prop.metaType(), QMetaType(QMetaType::Int));
+
+    QVERIFY(!prop.notifySignal().isValid());
+}
+
+
+
+void tst_Moc::observerMetaCall()
+{
+    const auto metaObject = &ClassWithQPropertyMembers::staticMetaObject;
+    QMetaProperty prop = metaObject->property(metaObject->indexOfProperty("publicProperty"));
+    QVERIFY(prop.isValid());
+
+    ClassWithQPropertyMembers instance;
+
+    int observerCallCount = 0;
+
+    QProperty<int> dummy;
+    auto handler = dummy.onValueChanged([&observerCallCount]() {
+        ++observerCallCount;
+    });
+
+    {
+        void *argv[] = { &handler };
+        instance.qt_metacall(QMetaObject::RegisterQPropertyObserver, prop.propertyIndex(), argv);
+    }
+
+    instance.publicProperty.setValue(100);
+    QCOMPARE(observerCallCount, 1);
+    instance.publicProperty.setValue(101);
+    QCOMPARE(observerCallCount, 2);
+}
+
+
+
+void tst_Moc::setQPRopertyBinding()
+{
+    const auto metaObject = &ClassWithQPropertyMembers::staticMetaObject;
+    QMetaProperty prop = metaObject->property(metaObject->indexOfProperty("publicProperty"));
+    QVERIFY(prop.isValid());
+
+    ClassWithQPropertyMembers instance;
+
+    bool bindingCalled = false;
+    auto binding = Qt::makePropertyBinding([&bindingCalled]() {
+        bindingCalled = true;
+        return 42;
+    });
+
+    {
+        void *argv[] = { &binding };
+        instance.qt_metacall(QMetaObject::SetQPropertyBinding, prop.propertyIndex(), argv);
+    }
+    QVERIFY(!bindingCalled); // not yet!
+
+    QCOMPARE(instance.publicProperty.value(), 42);
+    QVERIFY(bindingCalled); // but now it should've been called :)
+}
+
 QTEST_MAIN(tst_Moc)
 
 // the generated code must compile with QT_NO_KEYWORDS