1 files changed, 37 insertions, 1 deletions
diff --git a/tests/auto/qmqttclient/tst_qmqttclient.cpp b/tests/auto/qmqttclient/tst_qmqttclient.cpp
index 6c70007..b94bfd4 100644
--- a/tests/auto/qmqttclient/tst_qmqttclient.cpp
+++ b/tests/auto/qmqttclient/tst_qmqttclient.cpp
@@ -57,6 +57,7 @@ private Q_SLOTS:
     void dataIncludingZero();
     void publishLongTopic();
     void reconnect_QTBUG65726();
+    void openIODevice_QTBUG66955();
 private:
     QProcess m_brokerProcess;
     QString m_testBroker;
@@ -395,7 +396,7 @@ class FakeServer : public QObject
     Q_OBJECT
 public:
     FakeServer() {
-        server = new QTcpServer();
+        server = new QTcpServer(this);
         connect(server, &QTcpServer::newConnection, this, &FakeServer::createSocket);
         server->listen(QHostAddress::Any, 5726);
     }
@@ -447,6 +448,41 @@ void Tst_QMqttClient::reconnect_QTBUG65726()
     QTRY_COMPARE(client.error(), QMqttClient::NoError);
 }
 
+class IOTransport : public QIODevice
+{
+public:
+    bool open(OpenMode mode) override {
+        return QIODevice::open(mode);
+    }
+    qint64 readData(char *data, qint64 maxlen) override {
+        Q_UNUSED(data);
+        Q_UNUSED(maxlen);
+        return 0;
+    }
+    qint64 writeData(const char *data, qint64 len) override {
+        Q_UNUSED(data);
+        Q_UNUSED(len);
+        if (data[0] == 0x10)
+            written = 1;
+        else
+            qWarning() << "Received unknown/invalid data";
+        return len;
+    }
+    QAtomicInt written{0};
+};
+
+void Tst_QMqttClient::openIODevice_QTBUG66955()
+{
+    IOTransport trans;
+    trans.open(QIODevice::ReadWrite);
+
+    QMqttClient client;
+    client.setTransport(&trans, QMqttClient::IODevice);
+    client.connectToHost();
+
+    QTRY_COMPARE(trans.written, 1);
+}
+
 QTEST_MAIN(Tst_QMqttClient)
 
 #include "tst_qmqttclient.moc"