CMake: Introduce new lupdate/lrelease API

Add a new CMake API for lupdate and lrelease which is target-based and
aims to replace qt6_add_translation and qt6_create_translation.

    qt6_add_lupdate(my_app TS_FILES app_de.ts)
does the following:
- retrieves the sources from target my_app
- adds the target my_app_lupdate to create/update .ts files
- add the target update_translations to build all such *_lupdate
  targets

  qt6_add_lrelease(my_app TS_FILES app_en.ts)
does the following:
- adds the target my_app_lrelease to create .qm files
- adds my_app_lrelease as dependency to my_app such that
  .qm files are automatically updated.
- add the target release_translations to build all such *_lrelease
  targets

  qt6_add_translations(my_app TS_FILES app_en.ts)
does all of the above with one call.

The creation of the update_translations and release_translations targets
can be prevented.

Fixes: QTBUG-76410
Change-Id: Ibc8ed66e6cd3875447f4cf07d944227678997107
Reviewed-by: Kai Koehne <kai.koehne@qt.io>

5 files changed, 177 insertions, 1 deletions

diff --git a/tests/auto/cmake/CMakeLists.txt b/tests/auto/cmake/CMakeLists.txt
index d7e981e71..77641e8b0 100644
--- a/tests/auto/cmake/CMakeLists.txt
+++ b/tests/auto/cmake/CMakeLists.txt
@@ -28,7 +28,7 @@ project(qttools_cmake_tests)
 enable_testing()
 
 set(required_packages Core)
-set(optional_packages Widgets)
+set(optional_packages Widgets LinguistTools)
 
 # Setup the test when called as a completely standalone project.
 if(TARGET Qt6::Core)
@@ -61,3 +61,7 @@ if (TARGET Qt6::Widgets)
     _qt_internal_test_expect_pass(test_uiplugin_module)
     _qt_internal_test_expect_pass(test_uiplugin_via_designer)
 endif()
+
+if(TARGET Qt6::lupdate)
+    _qt_internal_test_expect_pass(test_translation_api)
+endif()
diff --git a/tests/auto/cmake/test_translation_api/CMakeLists.txt b/tests/auto/cmake/test_translation_api/CMakeLists.txt
new file mode 100644
index 000000000..8bd69f9fe
--- /dev/null
+++ b/tests/auto/cmake/test_translation_api/CMakeLists.txt
@@ -0,0 +1,74 @@
+cmake_minimum_required(VERSION 3.15)
+
+project(test_update_translation_macro)
+
+find_package(Qt6 REQUIRED COMPONENTS Core LinguistTools)
+
+function(create_app target)
+    add_executable(${target}
+        myi18nobject.cpp)
+
+    target_include_directories(${target}
+        PRIVATE ${CMAKE_CURRENT_SOURCE_DIR}/some_dir)
+
+    target_link_libraries(${target} Qt6::Core)
+endfunction()
+
+function(expect_target target)
+    if(NOT TARGET ${target})
+        message(FATAL_ERROR "Expected target '${target}' does not exist.")
+    endif()
+endfunction()
+
+function(not_expect_target target)
+    if(TARGET ${target})
+        message(FATAL_ERROR "Target '${target}' exists unexpectedly.")
+    endif()
+endfunction()
+
+# Test NO_GLOBAL_TARGET for lupdate.
+create_app(app1)
+qt6_add_lupdate(app1
+    NO_GLOBAL_TARGET
+    TS_FILES myobject_de.ts)
+expect_target(app1_lupdate)
+not_expect_target(app1_lrelease)
+not_expect_target(update_translations)
+not_expect_target(release_translations)
+
+# Test NO_GLOBAL_TARGET for lrelease.
+create_app(app2)
+qt6_add_lrelease(app2
+    NO_GLOBAL_TARGET
+    TS_FILES myobject_de.ts myobject_en.ts)
+not_expect_target(app2_lupdate)
+expect_target(app2_lrelease)
+not_expect_target(update_translations)
+not_expect_target(release_translations)
+
+# Typical usage of qt_add_lupdate/qt_add_lrelease. Pass some options for good measure.
+create_app(app3)
+qt6_add_lupdate(app3
+    TS_FILES myobject_no.ts myobject_fi.ts
+    OPTIONS -source-language en_US)
+qt6_add_lrelease(app3
+    TS_FILES myobject_no.ts myobject_fi.ts
+    OPTIONS -compress)
+expect_target(app3_lupdate)
+expect_target(app3_lrelease)
+expect_target(release_translations)
+
+# Now do the same with qt6_add_translations.
+create_app(app4)
+qt6_add_translations(app4
+    TS_FILES myobject_no.ts myobject_fi.ts
+    LUPDATE_OPTIONS -source-language en_US
+    LRELEASE_OPTIONS -compress)
+expect_target(app4_lupdate)
+expect_target(app4_lrelease)
+expect_target(release_translations)
+
+# Build the update_translations target
+add_custom_target(my_all_target
+    ALL
+    DEPENDS update_translations)
diff --git a/tests/auto/cmake/test_translation_api/myi18nobject.cpp b/tests/auto/cmake/test_translation_api/myi18nobject.cpp
new file mode 100644
index 000000000..eacce70db
--- /dev/null
+++ b/tests/auto/cmake/test_translation_api/myi18nobject.cpp
@@ -0,0 +1,49 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Copyright (C) 2016 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Stephen Kelly <stephen.kelly@kdab.com>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** 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 General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QDebug>
+#include <QCoreApplication>
+#include <QLocale>
+#include <QTranslator>
+
+#include "some_include.h"
+
+int main(int argc, char **argv)
+{
+    QCoreApplication app(argc, argv);
+    QTranslator *myappTranslator = new QTranslator;
+    QString localeName = QLocale::system().name();
+    if (!myappTranslator->load("myobject_" + localeName + ".qm", qApp->applicationDirPath()))
+        return 1;
+    myappTranslator->setObjectName("myobject_" + localeName);
+    app.installTranslator(myappTranslator);
+
+    qDebug() << QObject::tr("Hello, world!");
+    return 0;
+}
diff --git a/tests/auto/cmake/test_translation_api/myobject_de.ts b/tests/auto/cmake/test_translation_api/myobject_de.ts
new file mode 100644
index 000000000..fb4ee6f55
--- /dev/null
+++ b/tests/auto/cmake/test_translation_api/myobject_de.ts
@@ -0,0 +1,12 @@
+<?xml version="1.0" encoding="utf-8"?>
+<!DOCTYPE TS>
+<TS version="2.1" language="de_DE">
+<context>
+    <name>QObject</name>
+    <message>
+        <location filename="myi18nobject.cpp" line="47"/>
+        <source>Hello, world!</source>
+        <translation type="unfinished"></translation>
+    </message>
+</context>
+</TS>
diff --git a/tests/auto/cmake/test_translation_api/some_dir/some_include.h b/tests/auto/cmake/test_translation_api/some_dir/some_include.h
new file mode 100644
index 000000000..627b9e9e3
--- /dev/null
+++ b/tests/auto/cmake/test_translation_api/some_dir/some_include.h
@@ -0,0 +1,37 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Copyright (C) 2016 Klarälvdalens Datakonsult AB, a KDAB Group company, info@kdab.com, author Stephen Kelly <stephen.kelly@kdab.com>
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the test suite of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:GPL-EXCEPT$
+** 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 General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 3 as published by the Free Software
+** Foundation with exceptions as appearing in the file LICENSE.GPL3-EXCEPT
+** included in the packaging of this file. Please review the following
+** information to ensure the GNU General Public License requirements will
+** be met: https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#ifndef SOME_INCLUDE_H
+#define SOME_INCLUDE_H
+
+enum {
+  Non_Empty_File
+};
+
+#endif