Avoid dynamic lookup of signal handler arguments

Rewrite signal handlers to include the parameters
in the rewrite. Also check whether parameters are
actually used when possible, and if not don't
provide them to the expression.

Change-Id: I7d65c05f4639979dd61035cf7478119ef7647c25
Reviewed-by: Matthew Vogt <matthew.vogt@nokia.com>
Reviewed-by: Kent Hansen <kent.hansen@nokia.com>

1 files changed, 19 insertions, 1 deletions

diff --git a/src/qml/qml/qqmlcompiler.cpp b/src/qml/qml/qqmlcompiler.cpp
index ec1d19dd4e..ee8b30aab7 100644
--- a/src/qml/qml/qqmlcompiler.cpp
+++ b/src/qml/qml/qqmlcompiler.cpp
@@ -1323,8 +1323,17 @@ void QQmlCompiler::genObjectBody(QQmlScript::Object *obj)
 
             Instruction::StoreSignal store;
             store.signalIndex = prop->index;
-            const QString &rewrite = rewriteSignalHandler(v->value, prop->name().toString());
+
+            const QList<QByteArray> &parameterNameList = obj->metatype->signalParameterNames(prop->index);
+            QQmlRewrite::RewriteSignalHandler rewriter;
+            int count = 0;
+            const QString &rewrite = rewriter(v->value.asAST(), v->value.asScript(),
+                                              prop->name().toString(),
+                                              obj->metatype->signalParameterStringForJS(prop->index, &count),
+                                              parameterNameList);
             store.value = output->indexForByteArray(rewrite.toUtf8());
+            store.parameterCount =
+                    (rewriter.parameterAccess() == QQmlRewrite::RewriteSignalHandler::ParametersUnaccessed) ? 0 : count;
             store.context = v->signalExpressionContextStack;
             store.line = v->location.start.line;
             store.column = v->location.start.column;
@@ -1694,6 +1703,15 @@ bool QQmlCompiler::buildSignal(QQmlScript::Property *prop, QQmlScript::Object *o
             if (script.isEmpty())
                 COMPILE_EXCEPTION(prop, tr("Empty signal assignment"));
 
+            //all handlers should be on the original, rather than cloned signals in order
+            //to ensure all parameters are available (see qqmlboundsignal constructor for more details)
+            prop->index = obj->metatype->originalClone(prop->index);
+
+            QString errorString;
+            obj->metatype->signalParameterStringForJS(prop->index, 0, &errorString);
+            if (!errorString.isEmpty())
+                COMPILE_EXCEPTION(prop, errorString);
+
             prop->values.first()->signalExpressionContextStack = ctxt.stack;
         }
     }