Add support for parameterNames in Signals

There were many uses cases when a proper interaction
between Python and Qml was needed, one of them was
the case to emit signals from Python an get those values
via an argument name in QML.

A simple example describing this situation can be found
in PYSIDE-634:

Python:
    sumResult = Signal(int, arguments=["sum"])
    sumResult.emit(42)
Qml:
    onSumResult: console.log(sum) // will print 42

A test case based on the same example was added.

Change-Id: I0908f97d88eaadc0c02d81bc4daca936f72f6c6a
Fixes: PYSIDE-634
Reviewed-by: Christian Tismer <tismer@stackless.com>

1 files changed, 11 insertions, 2 deletions

diff --git a/sources/pyside2/libpyside/dynamicqmetaobject.cpp b/sources/pyside2/libpyside/dynamicqmetaobject.cpp
index c5de54aa0..857d242a2 100644
--- a/sources/pyside2/libpyside/dynamicqmetaobject.cpp
+++ b/sources/pyside2/libpyside/dynamicqmetaobject.cpp
@@ -467,8 +467,17 @@ void MetaObjectBuilderPrivate::parsePythonType(PyTypeObject *type)
                 data->data->signalName = Shiboken::String::toCString(key);
                 for (const auto &s : data->data->signatures) {
                     const auto sig = data->data->signalName + '(' + s.signature + ')';
-                    if (m_baseObject->indexOfSignal(sig) == -1)
-                        m_builder->addSignal(sig);
+                    if (m_baseObject->indexOfSignal(sig) == -1) {
+                        // Registering the parameterNames to the QMetaObject (PYSIDE-634)
+                        // from:
+                        //     Signal(..., arguments=['...', ...]
+                        // the arguments are now on data-data->signalArguments
+                        if (!data->data->signalArguments->isEmpty()) {
+                            m_builder->addSignal(sig).setParameterNames(*data->data->signalArguments);
+                        } else {
+                            m_builder->addSignal(sig);
+                        }
+                    }
                 }
             }
         }