Add test of the static plugin with resources

The test follows up the discussion about tests related to the static
plugin resources:

https://codereview.qt-project.org/c/qt/qtbase/+/341203/6/tests/auto/other/init_resources_static_plugin/CMakeLists.txt#1

It emulates the static plugin that contains resource files. Since the
test already exposed few issues related to the resource object linking
it makes sense to have it in test set.

Change-Id: I62621c2db1eae6ae5842ba52035774a662d93423
Reviewed-by: Alexandru Croitor <alexandru.croitor@qt.io>

tests/auto/cmake/CMakeLists.txt

@@ -216,3 +216,5 @@ _qt_internal_test_expect_pass(test_add_resources_binary_generated
                               BINARY test_add_resources_binary_generated)
 
 include(test_plugin_shared_static_flavor.cmake)
+_qt_internal_test_expect_pass(test_init_resources_static_plugin
+                              BINARY test_init_resources_static_plugin)

tests/auto/cmake/test_init_resources_static_plugin/CMakeLists.txt

@@ -0,0 +1,52 @@
+cmake_minimum_required(VERSION 3.16)
+
+if(DEFINED CMAKE_Core_MODULE_MAJOR_VERSION)
+    set(project_version "${CMAKE_Core_MODULE_MAJOR_VERSION}.\
+${CMAKE_Core_MODULE_MINOR_VERSION}.${CMAKE_Core_MODULE_PATCH_VERSION}"
+    )
+else()
+    set(project_version "6.0.0")
+endif()
+
+project(TestInitResourcesStaticPlugin
+        LANGUAGES CXX
+        VERSION "${project_version}"
+)
+
+find_package(Qt6 COMPONENTS Core BuildInternals CONFIG REQUIRED)
+qt_prepare_standalone_project()
+
+find_package(Qt6 COMPONENTS Gui Test CONFIG REQUIRED) # Add gui since Core have no plugin types
+
+qt_internal_add_plugin(TestInitResourcesStaticPlugin STATIC
+    OUTPUT_NAME
+        testinitresourcesstaticplugin
+    TYPE generic
+    SOURCES
+        pluginmain.cpp
+    SKIP_INSTALL
+    LIBRARIES
+        Qt::Core
+)
+
+qt_internal_add_resource(TestInitResourcesStaticPlugin "teststaticplugin1"
+    PREFIX
+        "/teststaticplugin1"
+    FILES
+        "testfile1.txt"
+)
+
+qt_internal_add_resource(TestInitResourcesStaticPlugin "teststaticplugin2"
+    PREFIX
+        "/teststaticplugin2"
+    FILES
+        "testfile2.txt"
+)
+
+qt_internal_add_test(test_init_resources_static_plugin
+    SOURCES
+        test_init_resources_static_plugin.cpp
+    LIBRARIES
+        Qt::Core
+        TestInitResourcesStaticPlugin
+)

tests/auto/cmake/test_init_resources_static_plugin/pluginmain.cpp

@@ -0,0 +1,60 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** 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-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtCore/qfile.h>
+#include <QtCore/qdebug.h>
+
+QT_BEGIN_NAMESPACE
+
+class TestStaticPlugin : public QObject
+{
+    Q_OBJECT
+    Q_PLUGIN_METADATA(IID "TestStaticPlugin" URI "qt.teststaticplugin")
+public:
+    TestStaticPlugin() = default;
+    Q_INVOKABLE bool checkResources()
+    {
+        return QFile::exists(":/teststaticplugin1/testfile1.txt")
+                && QFile::exists(":/teststaticplugin2/testfile2.txt");
+    }
+};
+
+QT_END_NAMESPACE
+
+#include "pluginmain.moc"

tests/auto/cmake/test_init_resources_static_plugin/test_init_resources_static_plugin.cpp

@@ -0,0 +1,69 @@
+/****************************************************************************
+**
+** Copyright (C) 2021 The Qt Company Ltd.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of the QtCore module of the Qt Toolkit.
+**
+** $QT_BEGIN_LICENSE:LGPL$
+** 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 Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 3 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL3 included in the
+** packaging of this file. Please review the following information to
+** ensure the GNU Lesser General Public License version 3 requirements
+** will be met: https://www.gnu.org/licenses/lgpl-3.0.html.
+**
+** GNU General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU
+** General Public License version 2.0 or (at your option) the GNU General
+** Public license version 3 or any later version approved by the KDE Free
+** Qt Foundation. The licenses are as published by the Free Software
+** Foundation and appearing in the file LICENSE.GPL2 and LICENSE.GPL3
+** 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-2.0.html and
+** https://www.gnu.org/licenses/gpl-3.0.html.
+**
+** $QT_END_LICENSE$
+**
+****************************************************************************/
+
+#include <QtTest/QtTest>
+#include <QtCore/qfile.h>
+#include <QtCore/qobject.h>
+#include <QtCore/qpluginloader.h>
+#include <QtPlugin>
+
+Q_IMPORT_PLUGIN(TestStaticPlugin)
+
+class TestInitResourcesStaticPlugin : public QObject
+{
+    Q_OBJECT
+private slots:
+    void resourceFilesExist();
+};
+
+void TestInitResourcesStaticPlugin::resourceFilesExist()
+{
+    bool result = false;
+    for (QObject *obj : QPluginLoader::staticInstances()) {
+        if (obj->metaObject()->className() == QLatin1String("TestStaticPlugin")) {
+            QMetaObject::invokeMethod(obj, "checkResources", Qt::DirectConnection,
+                                      Q_RETURN_ARG(bool, result));
+        }
+        break;
+    }
+    QVERIFY(result);
+}
+
+QTEST_MAIN(TestInitResourcesStaticPlugin)
+#include "test_init_resources_static_plugin.moc"