Remove Custom Type Example and Custom Type Sending Example

The whole Q_DECLARE_METATYPE part is superfluous in these two examples,
as QVariant works with any type as long as it is copy-constructible.
And QVariant will call the equivalent of qRegisterMetaType, so that
doesn't need to happen, either.
Showing how to integrate the type with qDebug is fine in theory, but
also a repetition of content that can be found in other places.

Given that there isn't much else being shown in these two examples, it's
better to remove them from examples and move them to manual tests.

Some parts of "Custom Type Example" were used as snippets in other
documentations under qtbase/src/corelib. So, they were added in
customtypeexample.cpp file in the snippets folder.

Fixes: QTBUG-117001
Pick-to: 6.6 6.5
Change-Id: I45b16338912e3f7394cbb5169642bd31af32d5e1
Reviewed-by: Ivan Solovev <ivan.solovev@qt.io>

examples/corelib/tools/CMakeLists.txt

@@ -5,5 +5,3 @@ if(NOT TARGET Qt6::Widgets)
     return()
 endif()
 qt_internal_add_example(contiguouscache)
-qt_internal_add_example(customtype)
-qt_internal_add_example(customtypesending)

examples/corelib/tools/customtype/CMakeLists.txt

@@ -1,37 +0,0 @@
-# Copyright (C) 2022 The Qt Company Ltd.
-# SPDX-License-Identifier: BSD-3-Clause
-
-cmake_minimum_required(VERSION 3.16)
-project(customtype LANGUAGES CXX)
-
-if(NOT DEFINED INSTALL_EXAMPLESDIR)
-    set(INSTALL_EXAMPLESDIR "examples")
-endif()
-
-set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/corelib/tools/customtype")
-
-find_package(Qt6 REQUIRED COMPONENTS Core Gui Widgets)
-
-qt_standard_project_setup()
-
-qt_add_executable(customtype
-    main.cpp
-    message.cpp message.h
-)
-
-set_target_properties(customtype PROPERTIES
-    WIN32_EXECUTABLE TRUE
-    MACOSX_BUNDLE TRUE
-)
-
-target_link_libraries(customtype PRIVATE
-    Qt6::Core
-    Qt6::Gui
-    Qt6::Widgets
-)
-
-install(TARGETS customtype
-    RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
-    BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
-    LIBRARY DESTINATION "${INSTALL_EXAMPLEDIR}"
-)

examples/corelib/tools/customtype/customtype.pro

@@ -1,8 +0,0 @@
-HEADERS   = message.h
-SOURCES   = main.cpp \
-            message.cpp
-QT += widgets
-
-# install
-target.path = $$[QT_INSTALL_EXAMPLES]/corelib/tools/customtype
-INSTALLS += target

examples/corelib/tools/customtypesending/CMakeLists.txt

@@ -1,38 +0,0 @@
-# Copyright (C) 2022 The Qt Company Ltd.
-# SPDX-License-Identifier: BSD-3-Clause
-
-cmake_minimum_required(VERSION 3.16)
-project(customtypesending LANGUAGES CXX)
-
-if(NOT DEFINED INSTALL_EXAMPLESDIR)
-    set(INSTALL_EXAMPLESDIR "examples")
-endif()
-
-set(INSTALL_EXAMPLEDIR "${INSTALL_EXAMPLESDIR}/corelib/tools/customtypesending")
-
-find_package(Qt6 REQUIRED COMPONENTS Core Gui Widgets)
-
-qt_standard_project_setup()
-
-qt_add_executable(customtypesending
-    main.cpp
-    message.cpp message.h
-    window.cpp window.h
-)
-
-set_target_properties(customtypesending PROPERTIES
-    WIN32_EXECUTABLE TRUE
-    MACOSX_BUNDLE TRUE
-)
-
-target_link_libraries(customtypesending PRIVATE
-    Qt6::Core
-    Qt6::Gui
-    Qt6::Widgets
-)
-
-install(TARGETS customtypesending
-    RUNTIME DESTINATION "${INSTALL_EXAMPLEDIR}"
-    BUNDLE DESTINATION "${INSTALL_EXAMPLEDIR}"
-    LIBRARY DESTINATION "${INSTALL_EXAMPLEDIR}"
-)

examples/corelib/tools/doc/src/customtype.qdoc

@@ -1,111 +0,0 @@
-// Copyright (C) 2016 The Qt Company Ltd.
-// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GFDL-1.3-no-invariants-only
-
-/*!
-    \example tools/customtype
-    \title Custom Type Example
-
-    \brief The Custom Type example shows how to integrate a custom type into Qt's
-    meta-object system.
-
-    Contents:
-
-    \tableofcontents
-
-    \section1 Overview
-
-    Qt provides a range of standard value types that are used to provide
-    rich and meaningful APIs. These types are integrated with the meta-object
-    system, enabling them to be stored in QVariant objects, written out in
-    debugging information and sent between components in signal-slot
-    communication.
-
-    Custom types can also be integrated with the meta-object system as long as
-    they are written to conform to some simple guidelines. In this example, we
-    introduce a simple \c Message class, we describe how we make it work with
-    QVariant, and we show how it can be extended to generate a printable
-    representation of itself for use in debugging output.
-
-    \section1 The Message Class Definition
-
-    The \c Message class is a simple value class that contains two pieces
-    of information (a QString and a QStringList), each of which can be read
-    using trivial getter functions:
-
-    \snippet tools/customtype/message.h custom type definition
-
-    The default constructor, copy constructor and destructor are
-    all required, and must be public, if the type is to be integrated into the
-    meta-object system. Other than this, we are free to implement whatever we
-    need to make the type do what we want, so we also include a constructor
-    that lets us set the type's data members.
-
-    To enable the type to be used with QVariant, we declare it using the
-    Q_DECLARE_METATYPE() macro:
-
-    \snippet tools/customtype/message.h custom type meta-type declaration
-
-    We do not need to write any additional code to accompany this macro.
-
-    To allow us to see a readable description of each \c Message object when it
-    is sent to the debug output stream, we define a streaming operator:
-
-    \snippet tools/customtype/message.h custom type streaming operator
-
-    This facility is useful if you need to insert tracing statements in your
-    code for debugging purposes.
-
-    \section1 The Message Class Implementation
-
-    The streaming operator is implemented in the following way:
-
-    \snippet tools/customtype/message.cpp custom type streaming operator
-
-    Here, we want to represent each value depending on how many lines are stored
-    in the message body. We stream text to the QDebug object passed to the
-    operator and return the QDebug object obtained from its maybeSpace() member
-    function; this is described in more detail in the
-    \l{Creating Custom Qt Types#Making the Type Printable}{Creating Custom Qt Types}
-    document.
-
-    We include the code for the getter functions for completeness:
-
-    \snippet tools/customtype/message.cpp getter functions
-
-    With the type fully defined, implemented, and integrated with the
-    meta-object system, we can now use it.
-
-    \section1 Using the Message
-
-    In the example's \c{main()} function, we show how a \c Message object can
-    be printed to the console by sending it to the debug stream:
-
-    \snippet tools/customtype/main.cpp printing a custom type
-
-    You can use the type with QVariant in exactly the same way as you would
-    use standard Qt value types. Here's how to store a value using the
-    QVariant::setValue() function:
-
-    \snippet tools/customtype/main.cpp storing a custom value
-
-    Alternatively, the QVariant::fromValue() function can be used if
-    you are using a compiler without support for member template
-    functions.
-
-    The value can be retrieved using the QVariant::value() member template
-    function:
-
-    \snippet tools/customtype/main.cpp retrieving a custom value
-
-    \section1 Further Reading
-
-    The custom \c Message type can also be used with direct signal-slot
-    connections.
-
-    To register a custom type for use with queued signals and slots, such as
-    those used in cross-thread communication, see the
-    \l{Queued Custom Type} example.
-
-    More information on using custom types with Qt can be found in the
-    \l{Creating Custom Qt Types} document.
-*/

examples/corelib/tools/tools.pro

@@ -1,6 +1,4 @@
 requires(qtHaveModule(widgets))
 
 TEMPLATE      = subdirs
-SUBDIRS       = contiguouscache \
-                customtype \
-                customtypesending
+SUBDIRS       = contiguouscache

src/corelib/doc/snippets/customtype/customtypeexample.cpp

@@ -0,0 +1,90 @@
+// Copyright (C) 2016 The Qt Company Ltd.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR BSD-3-Clause
+#include <QCoreApplication>
+#include <QDebug>
+#include <QVariant>
+
+//message.h
+
+//! [custom type definition]
+class Message
+{
+public:
+    Message() = default;
+    ~Message() = default;
+    Message(const Message &) = default;
+    Message &operator=(const Message &) = default;
+
+    Message(const QString &body, const QStringList &headers);
+
+    QStringView body() const;
+    QStringList headers() const;
+
+private:
+    QString m_body;
+    QStringList m_headers;
+};
+//! [custom type definition]
+
+//! [custom type meta-type declaration]
+Q_DECLARE_METATYPE(Message);
+//! [custom type meta-type declaration]
+
+//! [custom type streaming operator declaration]
+QDebug operator<<(QDebug dbg, const Message &message);
+//! [custom type streaming operator declaration]
+
+// message.cpp
+
+//! [custom type streaming operator]
+QDebug operator<<(QDebug dbg, const Message &message)
+{
+    const QList<QStringView> pieces = message.body().split(u"\r\n", Qt::SkipEmptyParts);
+    if (pieces.isEmpty())
+        dbg.nospace() << "Message()";
+    else if (pieces.size() == 1)
+        dbg.nospace() << "Message(" << pieces.first() << ")";
+    else
+        dbg.nospace() << "Message(" << pieces.first() << " ...)";
+    return dbg;
+}
+//! [custom type streaming operator]
+
+//! [getter functions]
+QStringView Message::body() const
+{
+    return m_body;
+}
+
+QStringList Message::headers() const
+{
+    return m_headers;
+}
+//! [getter functions]
+
+//main.cpp
+
+int main(int argc, char *argv[])
+{
+    QCoreApplication app(argc, argv);
+    QStringList headers;
+    headers << "Subject: Hello World"
+            << "From: address@example.com";
+    QString body = "This is a test.\r\n";
+    //! [printing a custom type]
+    Message message(body, headers);
+    qDebug() << "Original:" << message;
+    //! [printing a custom type]
+    //! [storing a custom value]
+    QVariant stored;
+    stored.setValue(message);
+    //! [storing a custom value]
+    qDebug() << "Stored:" << stored;
+    //! [retrieving a custom value]
+    Message retrieved = qvariant_cast<Message>(stored);
+    qDebug() << "Retrieved:" << retrieved;
+    retrieved = qvariant_cast<Message>(stored);
+    qDebug() << "Retrieved:" << retrieved;
+    //! [retrieving a custom value]
+    return 0;
+}

src/corelib/doc/src/custom-types.qdoc

@@ -37,7 +37,7 @@
 
     The following \c Message class definition includes these members:
 
-    \snippet tools/customtype/message.h custom type definition
+    \snippet customtype/customtypeexample.cpp custom type definition
 
     The class also provides a constructor for normal use and two public member functions
     that are used to obtain the private data.
@@ -53,11 +53,14 @@
     to this class, we invoke the Q_DECLARE_METATYPE() macro on the class in the header
     file where it is defined:
 
-    \snippet tools/customtype/message.h custom type meta-type declaration
+    \snippet customtype/customtypeexample.cpp custom type meta-type declaration
 
     This now makes it possible for \c Message values to be stored in QVariant objects
-    and retrieved later. See the \l{Custom Type Example} for code that demonstrates
-    this.
+    and retrieved later:
+
+    \snippet customtype/customtypeexample.cpp storing a custom value
+    \dots
+    \snippet customtype/customtypeexample.cpp retrieving a custom value
 
     The Q_DECLARE_METATYPE() macro also makes it possible for these values to be used as
     arguments to signals, but \e{only in direct signal-slot connections}.
@@ -107,18 +110,17 @@
     It is often quite useful to make a custom type printable for debugging purposes,
     as in the following code:
 
-    \snippet tools/customtype/main.cpp printing a custom type
+    \snippet customtype/customtypeexample.cpp printing a custom type
 
     This is achieved by creating a streaming operator for the type, which is often
     defined in the header file for that type:
 
-    \snippet tools/customtype/message.h custom type streaming operator
+    \snippet customtype/customtypeexample.cpp custom type streaming operator declaration
 
-    The implementation for the \c Message type in the \l{Custom Type Example}
-    goes to some effort to make the printable representation as readable as
-    possible:
+    The implementation for the \c Message type here goes to some effort to make the
+    printable representation as readable as possible:
 
-    \snippet tools/customtype/message.cpp custom type streaming operator
+    \snippet customtype/customtypeexample.cpp custom type streaming operator
 
     The output sent to the debug stream can, of course, be made as simple or as
     complicated as you like. Note that the value returned by this function is
@@ -131,8 +133,8 @@
     The Q_DECLARE_METATYPE() macro and qRegisterMetaType() function documentation
     contain more detailed information about their uses and limitations.
 
-    The \l{Custom Type Example}{Custom Type} and \l{Queued Custom Type} examples
-    show how to implement a custom type with the features outlined in this document.
+    The \l{Queued Custom Type} example shows how to implement a custom type with
+    the features outlined in this document.
 
     The \l{Debugging Techniques} document provides an overview of the debugging
     mechanisms discussed above.

src/corelib/io/qdebug.cpp

@@ -1068,7 +1068,7 @@ QDebug &QDebug::resetFormat()
 
     QDebugStateSaver is typically used in the implementation of an operator<<() for debugging:
 
-    \snippet tools/customtype/message.cpp custom type streaming operator
+    \snippet customtype/customtypeexample.cpp custom type streaming operator
 
     \since 5.1
 */

tests/manual/corelib/CMakeLists.txt

@@ -2,5 +2,4 @@
 # SPDX-License-Identifier: BSD-3-Clause
 
 add_subdirectory(time)
-# Needs conversion from qmake:
-# add_subdirectory(tools)
+add_subdirectory(tools)

tests/manual/corelib/tools/CMakeLists.txt

@@ -0,0 +1,12 @@
+# Copyright (C) 2023 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+add_subdirectory(customtype)
+add_subdirectory(customtypesending)
+# Needs conversion from qmake:
+# add_subdirectory(qhash)
+# add_subdirectory(qlist)
+# add_subdirectory(qmap)
+# add_subdirectory(qset)
+# add_subdirectory(qvarlengtharray)
+# add_subdirectory(qvector)

tests/manual/corelib/tools/customtype/CMakeLists.txt

@@ -0,0 +1,15 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+cmake_minimum_required(VERSION 3.16)
+
+qt_internal_add_manual_test(customtype
+    GUI
+    SOURCES
+        main.cpp
+        message.cpp message.h
+    LIBRARIES
+        Qt6::Core
+        Qt6::Gui
+        Qt6::Widgets
+)

tests/manual/corelib/tools/customtype/customtype.pro

@@ -0,0 +1,7 @@
+HEADERS   = message.h
+SOURCES   = main.cpp \
+            message.cpp
+QT += widgets
+INCLUDEPATH += .
+TARGET = customtype
+

tests/manual/corelib/tools/customtypesending/CMakeLists.txt

@@ -0,0 +1,16 @@
+# Copyright (C) 2022 The Qt Company Ltd.
+# SPDX-License-Identifier: BSD-3-Clause
+
+cmake_minimum_required(VERSION 3.16)
+
+qt_internal_add_manual_test(customtypesending
+    GUI
+    SOURCES
+        main.cpp
+        message.cpp message.h
+        window.cpp window.h
+    LIBRARIES
+        Qt6::Core
+        Qt6::Gui
+        Qt6::Widgets
+)

tests/manual/corelib/tools/customtypesending/customtypesending.pro

@@ -4,7 +4,6 @@ SOURCES   = main.cpp \
             message.cpp \
             window.cpp
 QT += widgets
+INCLUDEPATH += .
+TARGET = customtypesending
 
-# install
-target.path = $$[QT_INSTALL_EXAMPLES]/corelib/tools/customtypesending
-INSTALLS += target