Only connect to signal once per client object

We only disconnect once when all signals are disconnected, so we
should also only connect at most once per signal.

Change-Id: Ib3a866c3942bec5e06e3b301315bc83cdb972fab
Reviewed-by: Arno Rehn <a.rehn@menlosystems.com>
Reviewed-by: Frederik Gladhorn <frederik.gladhorn@qt.io>

2 files changed, 35 insertions, 3 deletions

diff --git a/examples/webchannel/shared/qwebchannel.js b/examples/webchannel/shared/qwebchannel.js
index d75e148..1e0d72a 100644
--- a/examples/webchannel/shared/qwebchannel.js
+++ b/examples/webchannel/shared/qwebchannel.js
@@ -261,9 +261,16 @@ function QObject(name, data, webChannel)
                 object.__objectSignals__[signalIndex] = object.__objectSignals__[signalIndex] || [];
                 object.__objectSignals__[signalIndex].push(callback);
 
-                if (!isPropertyNotifySignal && signalName !== "destroyed") {
-                    // only required for "pure" signals, handled separately for properties in propertyUpdate
-                    // also note that we always get notified about the destroyed signal
+                // only required for "pure" signals, handled separately for properties in propertyUpdate
+                if (isPropertyNotifySignal)
+                    return;
+
+                // also note that we always get notified about the destroyed signal
+                if (signalName === "destroyed")
+                    return;
+
+                // and otherwise we only need to be connected only once
+                if (object.__objectSignals__[signalIndex].length == 1) {
                     webChannel.exec({
                         type: QWebChannelMessageTypes.connectToSignal,
                         object: object.__id__,
diff --git a/tests/auto/qml/tst_webchannel.qml b/tests/auto/qml/tst_webchannel.qml
index 298376f..0069261 100644
--- a/tests/auto/qml/tst_webchannel.qml
+++ b/tests/auto/qml/tst_webchannel.qml
@@ -451,4 +451,29 @@ TestCase {
             0
         ]);
     }
+
+    function test_multiConnect()
+    {
+        var signalArgs = [];
+        function logSignalArgs(arg) {
+            signalArgs.push(arg);
+        }
+        var channel = client.createChannel(function(channel) {
+            var testObject = channel.objects.testObject;
+            testObject.testSignalInt.connect(logSignalArgs);
+            testObject.testSignalInt.connect(logSignalArgs);
+            testObject.triggerSignals();
+        });
+        client.awaitInit();
+
+        var msg = client.awaitMessage();
+        compare(msg.type, JSClient.QWebChannelMessageTypes.connectToSignal);
+        compare(msg.object, "testObject");
+
+        msg = client.awaitMessage();
+        compare(msg.type, JSClient.QWebChannelMessageTypes.invokeMethod);
+        client.awaitIdle();
+
+        compare(signalArgs, [42, 42, 1, 1, 0, 0]);
+    }
 }