qmltc: add cmake api and simplest file writer

Also update tests to include the generated file. While the
content is meaningless, it's good enough to check that the file
is include-able at this stage

Task-number: QTBUG-84368
Task-number: QTBUG-96040
Change-Id: I155826a52090c5b13d14be6330813dc5a27f28e5
Reviewed-by: Ulf Hermann <ulf.hermann@qt.io>

1 files changed, 81 insertions, 0 deletions

diff --git a/src/qml/doc/src/cmake/qt_target_compile_qml_to_cpp.qdoc b/src/qml/doc/src/cmake/qt_target_compile_qml_to_cpp.qdoc
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+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the documentation of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:FDL$
+** Commercial License Usage
+** Licensees holding valid commercial Qt licenses may use this file in
+** accordance with the commercial license agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and The Qt Company. For licensing terms
+** and conditions see https://www.qt.io/terms-conditions. For further
+** information use the contact form at https://www.qt.io/contact-us.
+**
+** GNU Free Documentation License Usage
+** Alternatively, this file may be used under the terms of the GNU Free
+** Documentation License version 1.3 as published by the Free Software
+** Foundation and appearing in the file included in the packaging of
+** this file. Please review the following information to ensure
+** the GNU Free Documentation License version 1.3 requirements
+** will be met: https://www.gnu.org/licenses/fdl-1.3.html.
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+/*!
+\page qt_target_compile_qml_to_cpp.html
+\ingroup cmake-commands-qtqml
+
+\title qt_target_compile_qml_to_cpp
+\target qt6_target_compile_qml_to_cpp
+
+\brief Compiles QML files (.qml) to C++ source code with Qml Type Compiler (qmltc).
+
+\section1 Synopsis
+
+\badcode
+qt_target_compile_qml_to_cpp(
+    target
+    FILES ...
+)
+
+\endcode
+
+\versionlessCMakeCommandsNote qt6_target_compile_qml_to_cpp()
+
+\section1 Description
+
+This command compiles the object structure of the passed QML files to C++ using
+qmltc. By default, qmltc generates lower-case \c{.h} and \c{.cpp} files for a
+given \c{.qml} file, so an arbitrary \c{HelloWorld.qml} ends up being compiled
+into \c{helloworld.h} and \c{helloworld.cpp}. The generated files are then
+automatically added to the target.
+
+\note This command is in technology preview and may change in future releases.
+
+\section1 Arguments
+
+The \c target specifies the name of the binary that the QML files belong to. In
+order for the compilation to succeed, the target is expected to be a valid QML
+module, defined with qt_add_qml_module() command.
+
+\c FILES lists the \c{.qml} files that are going to be compiled into C++. In
+most cases, all the target's QML files would be specified in the FILES. This
+way, FILES argument is equivalent to QML_FILES argument of the
+qt_add_qml_module() command.
+
+While processing FILES, the following source file properties are respected:
+\list
+    \li \c{QT_QMLTC_FILE_BASENAME}: use this source file property to specify a
+        non-default .h and .cpp file name, which might be useful to e.g. resolve
+        conflicting file names (imagine you have main.qml that is being
+        compiled, but main.h already exists, so #include "main.h" might not do
+        what you expect it to do). Unlike in the case of default behavior, the
+        QT_QMLTC_FILE_BASENAME is taken as is, without being lower-cased or
+        processed by any other means
+\endlist
+
+*/