Make QDBusPendingCallWatcher emit a signal if it is created on an

already-finished call.

This fixes a bit of a "surprise" when calling a local method (which
returns and finishes immediately) or when by accident calling a
function that returns QDBusReply instead of QDBusPendingCall/Reply.

Reviewed-by: Trust Me

2 files changed, 81 insertions, 2 deletions

diff --git a/src/dbus/qdbuspendingcall.cpp b/src/dbus/qdbuspendingcall.cpp
index 9753bbe..955f4a0 100644
--- a/src/dbus/qdbuspendingcall.cpp
+++ b/src/dbus/qdbuspendingcall.cpp
@@ -432,9 +432,14 @@ inline void QDBusPendingCallWatcherPrivate::_q_finished()
 QDBusPendingCallWatcher::QDBusPendingCallWatcher(const QDBusPendingCall &call, QObject *parent)
     : QObject(*new QDBusPendingCallWatcherPrivate, parent), QDBusPendingCall(call)
 {
-    if (d) {
-        if (!d->watcherHelper)
+    if (d) {                    // QDBusPendingCall::d
+        if (!d->watcherHelper) {
             d->watcherHelper = new QDBusPendingCallWatcherHelper;
+            if (isFinished()) {
+                // cause a signal emission anyways
+                QMetaObject::invokeMethod(d->watcherHelper, "finished", Qt::QueuedConnection);
+            }
+        }
         d->watcherHelper->add(this);
     }
 }
@@ -464,6 +469,7 @@ void QDBusPendingCallWatcher::waitForFinished()
         d->waitForFinished();
 
         // our signals were queued, so deliver them
+        QCoreApplication::sendPostedEvents(d->watcherHelper, QEvent::MetaCall);
         QCoreApplication::sendPostedEvents(this, QEvent::MetaCall);
     }
 }
diff --git a/tests/auto/qdbuspendingcall/tst_qdbuspendingcall.cpp b/tests/auto/qdbuspendingcall/tst_qdbuspendingcall.cpp
index 58707f1..947e8d6 100644
--- a/tests/auto/qdbuspendingcall/tst_qdbuspendingcall.cpp
+++ b/tests/auto/qdbuspendingcall/tst_qdbuspendingcall.cpp
@@ -90,6 +90,8 @@ private Q_SLOTS:
     void watcher();
     void watcher_error();
     void watcher_waitForFinished();
+    void watcher_waitForFinished_alreadyFinished();
+    void watcher_waitForFinished_alreadyFinished_eventLoop();
     void watcher_waitForFinished_error();
     void callInsideWaitForFinished();
 
@@ -375,6 +377,77 @@ void tst_QDBusPendingCall::watcher_waitForFinished()
     QVERIFY(args2.at(0).toStringList().contains(conn.baseService()));
 }
 
+void tst_QDBusPendingCall::watcher_waitForFinished_alreadyFinished()
+{
+    QDBusPendingCall ac = sendMessage();
+    QVERIFY(!ac.isFinished());
+    QVERIFY(!ac.isError());
+    QVERIFY(ac.reply().type() == QDBusMessage::InvalidMessage);
+
+    ac.waitForFinished();
+    QVERIFY(ac.isFinished());
+    QVERIFY(!ac.isError());
+
+    callCount = 0;
+    watchArgument = 0;
+
+    // create a watcher on an already-finished reply
+    QDBusPendingCallWatcher watch(ac);
+    connect(&watch, SIGNAL(finished(QDBusPendingCallWatcher*)),
+            SLOT(finished(QDBusPendingCallWatcher*)));
+
+    watch.waitForFinished();
+
+    QVERIFY(ac.isFinished());
+    QVERIFY(!ac.isError());
+
+    QCOMPARE(callCount, 1);
+    QCOMPARE(slotCalled, (int)FinishCalled);
+    QCOMPARE(watchArgument, &watch);
+    QVERIFY(!watch.isError());
+
+    const QVariantList args2 = ac.reply().arguments();
+    QVERIFY(!args2.isEmpty());
+    QVERIFY(args2.at(0).toStringList().contains(conn.baseService()));
+}
+
+void tst_QDBusPendingCall::watcher_waitForFinished_alreadyFinished_eventLoop()
+{
+    QDBusPendingCall ac = sendMessage();
+    QVERIFY(!ac.isFinished());
+    QVERIFY(!ac.isError());
+    QVERIFY(ac.reply().type() == QDBusMessage::InvalidMessage);
+
+    ac.waitForFinished();
+    QVERIFY(ac.isFinished());
+    QVERIFY(!ac.isError());
+
+    callCount = 0;
+    watchArgument = 0;
+
+    // create a watcher on an already-finished reply
+    QDBusPendingCallWatcher watch(ac);
+    connect(&watch, SIGNAL(finished(QDBusPendingCallWatcher*)),
+            SLOT(finished(QDBusPendingCallWatcher*)));
+    connect(&watch, SIGNAL(finished(QDBusPendingCallWatcher*)),
+            &QTestEventLoop::instance(), SLOT(exitLoop()));
+
+    QTestEventLoop::instance().enterLoop(1);
+    QVERIFY(!QTestEventLoop::instance().timeout());
+
+    QVERIFY(ac.isFinished());
+    QVERIFY(!ac.isError());
+
+    QCOMPARE(callCount, 1);
+    QCOMPARE(slotCalled, (int)FinishCalled);
+    QCOMPARE(watchArgument, &watch);
+    QVERIFY(!watch.isError());
+
+    const QVariantList args2 = ac.reply().arguments();
+    QVERIFY(!args2.isEmpty());
+    QVERIFY(args2.at(0).toStringList().contains(conn.baseService()));
+}
+
 void tst_QDBusPendingCall::watcher_waitForFinished_error()
 {
     QDBusPendingCall ac = sendError();