QJSEngine: Add a function to throw a pre-generated error object

It makes little sense that you can construct an error object but not
throw it. The test was definitely meant to actually throw the error
object, not return it.

[ChangeLog][QtQml] QJSEngine has gained an additional overload to the
throwError() method, with the effect that calling throwError() with a
character literal as argument is now ambiguous. You should explicitly
construct a QString instead.

Change-Id: I90c6c9edf10509daa142a86581d6a3f7ff45af2c
Reviewed-by: Maximilian Goldstein <max.goldstein@qt.io>
Reviewed-by: Fabian Kosmale <fabian.kosmale@qt.io>

3 files changed, 19 insertions, 2 deletions

diff --git a/src/qml/jsapi/qjsengine.cpp b/src/qml/jsapi/qjsengine.cpp
index f0e3e69fbb..37b5306897 100644
--- a/src/qml/jsapi/qjsengine.cpp
+++ b/src/qml/jsapi/qjsengine.cpp
@@ -939,6 +939,20 @@ void QJSEngine::throwError(QJSValue::ErrorType errorType, const QString &message
 }
 
 /*!
+    \overload throwError()
+
+    Throws a pre-constructed run-time \a error (exception). This way you can
+    use \l newErrorObject() to create the error and customize it as necessary.
+
+    \since 6.1
+    \sa {Script Exceptions}, newErrorObject()
+*/
+void QJSEngine::throwError(const QJSValue &error)
+{
+    m_v4Engine->throwError(QJSValuePrivate::asReturnedValue(&error));
+}
+
+/*!
  * Returns \c true if the last JavaScript execution resulted in an exception or
  * if throwError() was called. Otherwise returns \c false. Mind that evaluate()
  * catches any exceptions thrown in the evaluated code.
diff --git a/src/qml/jsapi/qjsengine.h b/src/qml/jsapi/qjsengine.h
index 9b02469b23..783f602c12 100644
--- a/src/qml/jsapi/qjsengine.h
+++ b/src/qml/jsapi/qjsengine.h
@@ -134,6 +134,7 @@ public:
 
     void throwError(const QString &message);
     void throwError(QJSValue::ErrorType errorType, const QString &message = QString());
+    void throwError(const QJSValue &error);
     bool hasError() const;
     QJSValue catchError();
 
diff --git a/tests/auto/qml/qjsengine/tst_qjsengine.cpp b/tests/auto/qml/qjsengine/tst_qjsengine.cpp
index a5316dce21..85d61a3537 100644
--- a/tests/auto/qml/qjsengine/tst_qjsengine.cpp
+++ b/tests/auto/qml/qjsengine/tst_qjsengine.cpp
@@ -4826,7 +4826,7 @@ void tst_QJSEngine::catchError()
 
 QJSValue tst_QJSEngine::throwingCppMethod1()
 {
-    qjsEngine(this)->throwError("blub");
+    qjsEngine(this)->throwError(QStringLiteral("blub"));
     return QJSValue(47);
 }
 
@@ -4837,7 +4837,9 @@ void tst_QJSEngine::throwingCppMethod2()
 
 QJSValue tst_QJSEngine::throwingCppMethod3()
 {
-    return qjsEngine(this)->newErrorObject(QJSValue::EvalError, "Something is wrong");
+    QJSEngine *engine = qjsEngine(this);
+    engine->throwError(engine->newErrorObject(QJSValue::EvalError, "Something is wrong"));
+    return QJSValue(31);
 }
 
 void tst_QJSEngine::mathMinMax()