Improve backward support

Do both variant conversions and qjsonvalue conversions.

Change-Id: I655395aa64c83ef62e8062d0820fdff437ebb156
Reviewed-by: Allan Sandfeld Jensen <allan.jensen@qt.io>

3 files changed, 33 insertions, 7 deletions

diff --git a/src/webchannel/qmetaobjectpublisher.cpp b/src/webchannel/qmetaobjectpublisher.cpp
index c956676..e641109 100644
--- a/src/webchannel/qmetaobjectpublisher.cpp
+++ b/src/webchannel/qmetaobjectpublisher.cpp
@@ -793,16 +793,16 @@ QVariant QMetaObjectPublisher::toVariant(const QJsonValue &value, int targetType
         return QVariant(target, reinterpret_cast<const void*>(&flagsValue));
     }
 
-    QVariant variant = QJsonValue::fromVariant(value);
-    // Try explicit conversion to the target type first. If that fails, fall
-    // back to generic conversion
+    QVariant variant = value.toVariant();
+    // Try variant conversion to the target type first. If that fails,
+    // try conversion over QJsonvalue.
     if (auto converted = variant; converted.convert(target)) {
         variant = std::move(converted);
-    } else {
-        if (targetType != QMetaType::QVariant) {
+    } else if (targetType != QMetaType::QVariant) {
+        if (QVariant converted = value; converted.convert(target))
+            variant = std::move(converted);
+        else
             qWarning() << "Could not convert argument" << value << "to target type" << target.name() << '.';
-        }
-        variant = value.toVariant();
     }
     return unwrapVariant(variant);
 }
diff --git a/tests/auto/webchannel/tst_webchannel.cpp b/tests/auto/webchannel/tst_webchannel.cpp
index 7305929..4884ea9 100644
--- a/tests/auto/webchannel/tst_webchannel.cpp
+++ b/tests/auto/webchannel/tst_webchannel.cpp
@@ -335,6 +335,16 @@ void TestWebChannel::setJsonValue(const QJsonValue& v)
     emit lastJsonValueChanged();
 }
 
+QUrl TestWebChannel::readUrl() const
+{
+    return m_lastUrl;
+}
+
+void TestWebChannel::setUrl(const QUrl& u)
+{
+    m_lastUrl = u;
+}
+
 QJsonObject TestWebChannel::readJsonObject() const
 {
     return m_lastJsonObject;
@@ -683,6 +693,15 @@ void TestWebChannel::testInvokeMethodConversion()
         auto retVal = channel.d_func()->publisher->invokeMethod(this, getterMethod, {});
         QCOMPARE(retVal, QVariant::fromValue(array));
     }
+    {
+        args[0] = QJsonValue::fromVariant(QUrl("aviancarrier:/ok"));
+        channel.d_func()->publisher->invokeMethod(this, "setUrl", args);
+        QVERIFY(m_lastUrl.isValid());
+        int getterMethod = metaObject()->indexOfMethod("readUrl()");
+        QVERIFY(getterMethod != -1);
+        auto retVal = channel.d_func()->publisher->invokeMethod(this, getterMethod, {});
+        QCOMPARE(retVal, args.at(0).toVariant().toUrl());
+    }
 }
 
 void TestWebChannel::testFunctionOverloading()
@@ -975,6 +994,9 @@ void TestWebChannel::testWrapValues_data()
                           << QJsonValue(QJsonObject{{"One", 1},
                                                     {"Two", 2}});
 
+    QTest::addRow("url") << QVariant::fromValue(QUrl("aviancarrier:/test"))
+                         << QJsonValue(QJsonValue(QString("aviancarrier:/test")));
+
     QTest::addRow("map") << QVariant::fromValue(QVariantMap{{"One", 1},
                                                             {"Two", 2}})
                          << QJsonValue(QJsonObject{{"One", 1},
diff --git a/tests/auto/webchannel/tst_webchannel.h b/tests/auto/webchannel/tst_webchannel.h
index 290457f..c1e3ee3 100644
--- a/tests/auto/webchannel/tst_webchannel.h
+++ b/tests/auto/webchannel/tst_webchannel.h
@@ -329,6 +329,9 @@ public slots:
     QJsonArray readJsonArray() const;
     void setJsonArray(const QJsonArray &v);
 
+    QUrl readUrl() const;
+    void setUrl(const QUrl &u);
+
     int readOverload(int i);
     QString readOverload(const QString &arg);
     QString readOverload(const QString &arg, int i);
@@ -396,6 +399,7 @@ private:
     QJsonValue m_lastJsonValue;
     QJsonObject m_lastJsonObject;
     QJsonArray m_lastJsonArray;
+    QUrl m_lastUrl;
 };
 
 QT_END_NAMESPACE