Fix handling of out-parameters that are of VARIANT-type

Qt knows about QVariant as a built-in meta type, QMetaType::QVariant. It
is no longer mapped to user type. COM objects expect that untyped out-
parameters, which are mapped to QVariant& by ActiveQt, are passed in as
VT_VARIANT|VT_BYREF.

Update our variant-conversion logic accordingly. If the typeName, which
comes from the generated function signature, is "QVariant", then
QMetaType::fromName(typeName) will always be QMetaType::QVariant, and
had to be passed as VT_VARIANT.

Fix the logic for deciding whether we have to write back the out-
parameters so that it works when QAxScript::call is used. We need to
write back no matter whether it's a property or a getter, so check
whether any bit is set, not if both are set.

Add some test for this. Not cherry-picking this further back, the
auto-test coverage of ActiveQt is not good enough to make sure that we
don't break any subtle usecases in e.g. QAxServer, and the usage of
QAxScript does not seem to be very wide.

Fixes: QTBUG-111718
Pick-to: 6.5
Change-Id: I239f71c3637ea9f32dff5123a8ada96e0a894371
Reviewed-by: Oliver Wolff <oliver.wolff@qt.io>
Reviewed-by: Friedemann Kleint <Friedemann.Kleint@qt.io>

1 files changed, 36 insertions, 0 deletions

diff --git a/tests/auto/qaxscript/tst_qaxscript.cpp b/tests/auto/qaxscript/tst_qaxscript.cpp
index 227e853..454b347 100644
--- a/tests/auto/qaxscript/tst_qaxscript.cpp
+++ b/tests/auto/qaxscript/tst_qaxscript.cpp
@@ -14,6 +14,7 @@ class tst_QAxScript : public QObject
 
 private slots:
     void scriptReturnValue();
+    void scriptOutParameters();
 };
 
 void tst_QAxScript::scriptReturnValue()
@@ -30,5 +31,40 @@ void tst_QAxScript::scriptReturnValue()
     QCOMPARE(result, QVariant(u"test"_s));
 }
 
+void tst_QAxScript::scriptOutParameters()
+{
+    QAxScriptManager scriptManager;
+    const auto scriptCode = uR"VB(
+    Function GetProductName(ByRef manufacturer, ByRef name, ByRef version)
+        manufacturer = "The Qt Company"
+        name = "ActiveQt"
+        version = 650
+        On Error Resume Next
+        GetProductName = 42
+    End Function
+    )VB"_s;
+
+    QAxScript *script = scriptManager.load(scriptCode, u"Test"_s, u"VBScript"_s);
+    QVERIFY2(script, "Unable to load script (CoInitializeEx() called?)");
+
+    QVariant returnValue;
+    QList<QVariant> results = {{}, {}, {}};
+
+    returnValue = script->scriptEngine()->dynamicCall("GetProductName(QVariant&,QVariant&,QVariant&)", results);
+    QCOMPARE(returnValue, 42);
+    QCOMPARE(results.size(), 3);
+    QCOMPARE(results.at(0), "The Qt Company");
+    QCOMPARE(results.at(1), "ActiveQt");
+    QCOMPARE(results.at(2), 650);
+
+    results = {{}, {}, {}};
+    returnValue = script->call("GetProductName(QVariant&,QVariant&,QVariant&)", results);
+    QCOMPARE(returnValue, 42);
+    QCOMPARE(results.size(), 3);
+    QCOMPARE(results.at(0), "The Qt Company");
+    QCOMPARE(results.at(1), "ActiveQt");
+    QCOMPARE(results.at(2), 650);
+}
+
 QTEST_MAIN(tst_QAxScript)
 #include "tst_qaxscript.moc"