QLocalSocket - deprecate ambiguous 'error' overloads

QLocalSocket::error is overloaded as a signal and an accessor (for the
error reported by the signal). This means connecting to the signal using
a pointer to member function would require ambiguity resolution. We
deprecate the old accessor (to be removed in Qt 6) and introduce a new one -
'socketError'.

[ChangeLog][Deprecation Notice] QLocalSocket::error() (the getter) is deprecated; superseded by socketError().

Task-number: QTBUG-80369
Change-Id: Iab346f7b4cd1024dee9e5ef71b4b7e09f6d95b12
Reviewed-by: Mårten Nordheim <marten.nordheim@qt.io>

src/network/socket/qlocalsocket.cpp

@@ -220,11 +220,25 @@ QT_BEGIN_NAMESPACE
 /*!
     \fn QLocalSocket::LocalSocketError QLocalSocket::error() const
 
+    \deprecated
+
+    Use socketError() instead.
+
+    Returns the type of error that last occurred.
+
+    \sa state(), errorString(), socketError()
+*/
+
+/*!
+    \fn QLocalSocket::LocalSocketError QLocalSocket::socketError() const
+    \since 5.15
+
     Returns the type of error that last occurred.
 
     \sa state(), errorString()
 */
 
+
 /*!
     \fn bool QLocalSocket::isValid() const
 
@@ -272,7 +286,7 @@ QT_BEGIN_NAMESPACE
     Waits until the socket is connected, up to \a msecs milliseconds. If the
     connection has been established, this function returns \c true; otherwise
     it returns \c false. In the case where it returns \c false, you can call
-    error() to determine the cause of the error.
+    socketError() to determine the cause of the error.
 
     The following example waits up to one second for a connection
     to be established:
@@ -291,7 +305,7 @@ QT_BEGIN_NAMESPACE
     connection was successfully disconnected, this function returns \c true;
     otherwise it returns \c false (if the operation timed out, if an error
     occurred, or if this QLocalSocket is already disconnected). In the case
-    where it returns \c false, you can call error() to determine the cause of
+    where it returns \c false, you can call socketError() to determine the cause of
     the error.
 
     The following example waits up to one second for a connection
@@ -337,7 +351,7 @@ QT_BEGIN_NAMESPACE
     connections, you will have to register it with Q_DECLARE_METATYPE() and
     qRegisterMetaType().
 
-    \sa error(), errorString(), {Creating Custom Qt Types}
+    \sa socketError(), errorString(), {Creating Custom Qt Types}
 */
 
 /*!
@@ -446,7 +460,7 @@ QString QLocalSocket::fullServerName() const
 /*!
     Returns the state of the socket.
 
-    \sa error()
+    \sa socketError()
  */
 QLocalSocket::LocalSocketState QLocalSocket::state() const
 {
@@ -466,7 +480,7 @@ bool QLocalSocket::isSequential() const
 
     The LocalServerError enumeration represents the errors that can occur.
     The most recent error can be retrieved through a call to
-    \l QLocalSocket::error().
+    \l QLocalSocket::socketError().
 
     \value ConnectionRefusedError The connection was refused by
         the peer (or timed out).

src/network/socket/qlocalsocket.h

@@ -97,7 +97,12 @@ public:
     virtual bool canReadLine() const override;
     virtual bool open(OpenMode openMode = ReadWrite) override;
     virtual void close() override;
-    LocalSocketError error() const;
+
+#if QT_DEPRECATED_SINCE(5, 15)
+    QT_DEPRECATED_X("Use socketError()") LocalSocketError error() const;
+#endif // QT_DEPRECATED_SINCE(5, 15)
+
+    LocalSocketError socketError() const;
     bool flush();
     bool isValid() const;
     qint64 readBufferSize() const;

src/network/socket/qlocalsocket_tcp.cpp

@@ -363,7 +363,14 @@ void QLocalSocket::disconnectFromServer()
     d->tcpSocket->disconnectFromHost();
 }
 
+#if QT_DEPRECATED_SINCE(5, 15)
 QLocalSocket::LocalSocketError QLocalSocket::error() const
+{
+    return socketError();
+}
+#endif // QT_DEPRECATED_SINCE(5, 15)
+
+QLocalSocket::LocalSocketError QLocalSocket::socketError() const
 {
     Q_D(const QLocalSocket);
     switch (d->tcpSocket->error()) {

src/network/socket/qlocalsocket_unix.cpp

@@ -461,7 +461,14 @@ void QLocalSocket::disconnectFromServer()
     d->unixSocket.disconnectFromHost();
 }
 
+#if QT_DEPRECATED_SINCE(5, 15)
 QLocalSocket::LocalSocketError QLocalSocket::error() const
+{
+    return socketError();
+}
+#endif // QT_DEPRECATED_SINCE(5, 15)
+
+QLocalSocket::LocalSocketError QLocalSocket::socketError() const
 {
     Q_D(const QLocalSocket);
     switch (d->unixSocket.socketError()) {

src/network/socket/qlocalsocket_win.cpp

@@ -330,7 +330,14 @@ void QLocalSocket::disconnectFromServer()
     }
 }
 
+#if QT_DEPRECATED_SINCE(5, 15)
 QLocalSocket::LocalSocketError QLocalSocket::error() const
+{
+    return socketError();
+}
+#endif // QT_DEPRECATED_SINCE(5, 15)
+
+QLocalSocket::LocalSocketError QLocalSocket::socketError() const
 {
     Q_D(const QLocalSocket);
     return d->error;

tests/auto/network/socket/qlocalsocket/socketprocess/main.cpp

@@ -65,8 +65,8 @@ bool runServer(int numberOfConnections)
             return false;
         }
         printf("server: data written\n");
-        if (socket->error() != QLocalSocket::UnknownSocketError) {
+        if (socket->socketError() != QLocalSocket::UnknownSocketError) {
-            fprintf(stderr, "server: socket error %d\n", socket->error());
+            fprintf(stderr, "server: socket error %d\n", socket->socketError());
             return false;
         }
     }
@@ -83,8 +83,8 @@ bool runClient()
         socket.connectToServer(serverName, QLocalSocket::ReadWrite);
         if (socket.waitForConnected())
             break;
-        if (socket.error() == QLocalSocket::ServerNotFoundError
+        if (socket.socketError() == QLocalSocket::ServerNotFoundError
-            || socket.error() == QLocalSocket::ConnectionRefusedError) {
+            || socket.socketError() == QLocalSocket::ConnectionRefusedError) {
             if (connectTimer.elapsed() > 5000) {
                 fprintf(stderr, "client: server not found or connection refused. Giving up.\n");
                 return false;

tests/auto/network/socket/qlocalsocket/tst_qlocalsocket.cpp

@@ -195,7 +195,7 @@ private slots:
     void slotError(QLocalSocket::LocalSocketError newError)
     {
         QVERIFY(errorString() != QLatin1String("Unknown error"));
-        QCOMPARE(error(), newError);
+        QCOMPARE(socketError(), newError);
     }
     void slotStateChanged(QLocalSocket::LocalSocketState newState)
     {
@@ -256,7 +256,7 @@ void tst_QLocalSocket::socket_basic()
     QCOMPARE(socket.canReadLine(), false);
     socket.close();
     socket.disconnectFromServer();
-    QCOMPARE(QLocalSocket::UnknownSocketError, socket.error());
+    QCOMPARE(QLocalSocket::UnknownSocketError, socket.socketError());
     QVERIFY(!socket.errorString().isEmpty());
     QCOMPARE(socket.flush(), false);
     QCOMPARE(socket.isValid(), false);
@@ -375,13 +375,13 @@ void tst_QLocalSocket::listenAndConnect()
             QVERIFY(socket->waitForConnected());
             QVERIFY(socket->isValid());
             QCOMPARE(socket->errorString(), QString("Unknown error"));
-            QCOMPARE(socket->error(), QLocalSocket::UnknownSocketError);
+            QCOMPARE(socket->socketError(), QLocalSocket::UnknownSocketError);
             QCOMPARE(socket->state(), QLocalSocket::ConnectedState);
             //QVERIFY(socket->socketDescriptor() != -1);
             QCOMPARE(spyError.count(), 0);
         } else {
             QVERIFY(!socket->errorString().isEmpty());
-            QVERIFY(socket->error() != QLocalSocket::UnknownSocketError);
+            QVERIFY(socket->socketError() != QLocalSocket::UnknownSocketError);
             QCOMPARE(socket->state(), QLocalSocket::UnconnectedState);
             //QCOMPARE(socket->socketDescriptor(), -1);
             QCOMPARE(qvariant_cast<QLocalSocket::LocalSocketError>(spyError.first()[0]),