V4: Handle all array-like containers when converting to QJsonArray

Commit b9bfdea0e2c6721d2306af0ecc44f88da9988957 removed specialized
code for QVariantList conversions by relying on sequences instead.

Some checks for sequences and other array-like containers were missed.
Add those and perform all calls to QJsonObject::toJsonArray through a
common QV4::Object interface.

Amends b9bfdea0e2c6721d2306af0ecc44f88da9988957

Fixes: QTBUG-123993
Change-Id: Ia671d556af4f2b4d44f652fa93182977d88621f2
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>
(cherry picked from commit 152e6716baeffd22c381df8c37c188b8eab7d9df)

7 files changed, 103 insertions, 11 deletions

diff --git a/src/qml/jsruntime/qv4jsonobject.cpp b/src/qml/jsruntime/qv4jsonobject.cpp
index a834cf20d5..d78d09113a 100644
--- a/src/qml/jsruntime/qv4jsonobject.cpp
+++ b/src/qml/jsruntime/qv4jsonobject.cpp
@@ -988,12 +988,16 @@ QJsonValue JsonObject::toJsonValue(const Value &value, V4ObjectSet &visitedObjec
 
     Q_ASSERT(value.isObject());
     Scope scope(value.as<Object>()->engine());
-    ScopedArrayObject a(scope, value);
-    if (a)
+    if (ScopedArrayObject a{ scope, value }) {
         return toJsonArray(a, visitedObjects);
-    ScopedObject o(scope, value);
-    if (o)
+    } else if (Scoped<QV4::Sequence> a{ scope, value }) {
+        return toJsonArray(a, visitedObjects);
+    } else if (Scoped<QmlListWrapper> lw{ scope, value }) {
+        return toJsonArray(lw, visitedObjects);
+    } else if (ScopedObject o{ scope, value }) {
         return toJsonObject(o, visitedObjects);
+    }
+
     return QJsonValue(value.toQString());
 }
 
@@ -1058,7 +1062,7 @@ QV4::ReturnedValue JsonObject::fromJsonArray(ExecutionEngine *engine, const QJso
     return a.asReturnedValue();
 }
 
-QJsonArray JsonObject::toJsonArray(const ArrayObject *a, V4ObjectSet &visitedObjects)
+QJsonArray JsonObject::toJsonArray(const Object *a, V4ObjectSet &visitedObjects)
 {
     QJsonArray result;
     if (!a)
diff --git a/src/qml/jsruntime/qv4jsonobject_p.h b/src/qml/jsruntime/qv4jsonobject_p.h
index abdfcf5d37..f6f63d7eb3 100644
--- a/src/qml/jsruntime/qv4jsonobject_p.h
+++ b/src/qml/jsruntime/qv4jsonobject_p.h
@@ -63,14 +63,13 @@ public:
     { V4ObjectSet visitedObjects; return toJsonValue(value, visitedObjects); }
     static inline QJsonObject toJsonObject(const QV4::Object *o)
     { V4ObjectSet visitedObjects; return toJsonObject(o, visitedObjects); }
-    static inline QJsonArray toJsonArray(const QV4::ArrayObject *a)
-    { V4ObjectSet visitedObjects; return toJsonArray(a, visitedObjects); }
+    static inline QJsonArray toJsonArray(const QV4::Object *o)
+    { V4ObjectSet visitedObjects; return toJsonArray(o, visitedObjects); }
 
 private:
     static QJsonValue toJsonValue(const QV4::Value &value, V4ObjectSet &visitedObjects);
     static QJsonObject toJsonObject(const Object *o, V4ObjectSet &visitedObjects);
-    static QJsonArray toJsonArray(const ArrayObject *a, V4ObjectSet &visitedObjects);
-
+    static QJsonArray toJsonArray(const Object *o, V4ObjectSet &visitedObjects);
 };
 
 class JsonParser
diff --git a/src/qml/jsruntime/qv4qobjectwrapper.cpp b/src/qml/jsruntime/qv4qobjectwrapper.cpp
index 8b86b7fab3..e554b31167 100644
--- a/src/qml/jsruntime/qv4qobjectwrapper.cpp
+++ b/src/qml/jsruntime/qv4qobjectwrapper.cpp
@@ -2350,8 +2350,8 @@ bool CallArgument::fromValue(QMetaType metaType, ExecutionEngine *engine, const
         return true;
     case QMetaType::QJsonArray: {
         Scope scope(engine);
-        ScopedArrayObject a(scope, value);
-        jsonArrayPtr = new (&allocData) QJsonArray(JsonObject::toJsonArray(a));
+        ScopedObject o(scope, value);
+        jsonArrayPtr = new (&allocData) QJsonArray(JsonObject::toJsonArray(o));
         return true;
     }
     case  QMetaType::QJsonObject: {
diff --git a/tests/auto/qml/qqmlengine/CMakeLists.txt b/tests/auto/qml/qqmlengine/CMakeLists.txt
index 7951baedb8..9745f31bdb 100644
--- a/tests/auto/qml/qqmlengine/CMakeLists.txt
+++ b/tests/auto/qml/qqmlengine/CMakeLists.txt
@@ -40,6 +40,7 @@ qt_add_qml_module(tst_qqmlengine_qml
     SOURCES
         "declarativelyregistered.h"
         "declarativelyregistered.cpp"
+        "variantlistQJsonConversion.h"
     RESOURCE_PREFIX
         "/"
     OUTPUT_DIRECTORY
diff --git a/tests/auto/qml/qqmlengine/data/variantListQJsonConversion.qml b/tests/auto/qml/qqmlengine/data/variantListQJsonConversion.qml
new file mode 100644
index 0000000000..fd0820a3c5
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/data/variantListQJsonConversion.qml
@@ -0,0 +1,18 @@
+import QtQuick
+import OnlyDeclarative
+
+Item {
+
+    MiscUtils {
+        id: miscUtils
+    }
+
+    Component.onCompleted: {
+        const varlist = miscUtils.createVariantList();
+        const obj = { test: varlist };
+        const listProperty = miscUtils.createQmlListProperty();
+        miscUtils.logArray(varlist);
+        miscUtils.logObject(obj);
+        miscUtils.logArray(listProperty);
+    }
+}
diff --git a/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp b/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp
index ec0d1b4386..56140836bf 100644
--- a/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp
+++ b/tests/auto/qml/qqmlengine/tst_qqmlengine.cpp
@@ -80,6 +80,7 @@ private slots:
     void lockedRootObject();
     void crossReferencingSingletonsDeletion();
     void bindingInstallUseAfterFree();
+    void variantListQJsonConversion();
 
 public slots:
     QObject *createAQObjectForOwnershipTest ()
@@ -1734,6 +1735,21 @@ void tst_qqmlengine::bindingInstallUseAfterFree()
     QVERIFY(o);
 }
 
+void tst_qqmlengine::variantListQJsonConversion()
+{
+    QQmlEngine engine;
+    QQmlComponent c(&engine, testFileUrl("variantListQJsonConversion.qml"));
+    QVERIFY2(c.isReady(), qPrintable(c.errorString()));
+
+    QTest::ignoreMessage(QtMsgType::QtDebugMsg, R"(["cpp","variant","list"])");
+    QTest::ignoreMessage(QtMsgType::QtDebugMsg, R"({"test":["cpp","variant","list"]})");
+    QTest::ignoreMessage(QtMsgType::QtDebugMsg,
+                         R"([{"objectName":"o0"},{"objectName":"o1"},{"objectName":"o2"}])");
+
+    QScopedPointer<QObject> o(c.create());
+    QVERIFY(o);
+}
+
 QTEST_MAIN(tst_qqmlengine)
 
 #include "tst_qqmlengine.moc"
diff --git a/tests/auto/qml/qqmlengine/variantlistQJsonConversion.h b/tests/auto/qml/qqmlengine/variantlistQJsonConversion.h
new file mode 100644
index 0000000000..7a47d9ff86
--- /dev/null
+++ b/tests/auto/qml/qqmlengine/variantlistQJsonConversion.h
@@ -0,0 +1,54 @@
+// Copyright (C) 2024 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0-only
+
+#ifndef VARIANTLIST_QJSON_CONVERSION_HPP
+#define VARIANTLIST_QJSON_CONVERSION_HPP
+
+#include "qqmlintegration.h"
+#include <QJsonObject>
+#include <QJsonArray>
+#include <QObject>
+#include <QJsonDocument>
+#include <QDebug>
+#include <QQmlEngine>
+#include <private/qjsvalue_p.h>
+#include <private/qqmllistwrapper_p.h>
+#include <private/qv4engine_p.h>
+#include <private/qv4jsonobject_p.h>
+
+class MiscUtils : public QObject
+{
+    Q_OBJECT
+    QML_ELEMENT
+
+public:
+    Q_INVOKABLE QVariantList createVariantList() const
+    {
+        return { QString("cpp"), QString("variant"), QString("list") };
+    }
+
+    Q_INVOKABLE QQmlListProperty<QObject> createQmlListProperty()
+    {
+        QV4::ExecutionEngine engine(qmlEngine(this));
+        static QObject objects[] = { QObject{}, QObject{}, QObject{} };
+        objects[0].setObjectName("o0");
+        objects[1].setObjectName("o1");
+        objects[2].setObjectName("o2");
+        static QList<QObject *> list{ &objects[0], &objects[1], &objects[2] };
+        return QQmlListProperty<QObject>(this, &list);
+    }
+
+    Q_INVOKABLE void logArray(const QJsonArray &arr) const
+    {
+        const auto str = QString(QJsonDocument(arr).toJson(QJsonDocument::Compact));
+        qDebug().noquote() << str;
+    }
+
+    Q_INVOKABLE void logObject(const QJsonObject &obj) const
+    {
+        const auto str = QString(QJsonDocument(obj).toJson(QJsonDocument::Compact));
+        qDebug().noquote() << str;
+    }
+};
+
+#endif // VARIANTLIST_QJSON_CONVERSION_HPP