Meson build plugin initial support

Most basic project management is implemented:
- Project config/build
- Build options accessible to user
- Lists most build targets
- Meson and Ninja added to kit setup
- Basic project file tree with files known by Meson
- Some basic meson and ninja process output parsing
- Some project templates

Missing features, that will come later:
- Configurable project tree layout
- Locators for Meson
- Build importer
- Access to Machine files for better user fine tuning
- ...

Fixes: QTCREATORBUG-18117
Change-Id: I2811e71562c113fb0fc6b6177bcf0698fa71ef63
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/mesonprojectmanager/settings/tools/kitaspect/ninjatoolkitaspect.cpp

@@ -0,0 +1,97 @@
+/****************************************************************************
+**
+** Copyright (C) 2020 Alexis Jeandet.
+** Contact: https://www.qt.io/licensing/
+**
+** This file is part of Qt Creator.
+**
+** 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.
+**
+****************************************************************************/
+
+#include "ninjatoolkitaspect.h"
+#include "toolkitaspectwidget.h"
+#include "utils/qtcassert.h"
+
+namespace MesonProjectManager {
+namespace Internal {
+
+static const char TOOL_ID[] = "MesonProjectManager.MesonKitInformation.Ninja";
+
+NinjaToolKitAspect::NinjaToolKitAspect()
+{
+    setObjectName(QLatin1String("NinjaKitAspect"));
+    setId(TOOL_ID);
+    setDisplayName(tr("Ninja Tool"));
+    setDescription(tr("The Ninja tool to use when building a project with Meson.<br>"
+                      "This setting is ignored when using other build systems."));
+    setPriority(9000);
+}
+
+ProjectExplorer::Tasks NinjaToolKitAspect::validate(const ProjectExplorer::Kit *k) const
+{
+    ProjectExplorer::Tasks tasks;
+    const auto tool = ninjaTool(k);
+    if (tool && !tool->isValid())
+        tasks << ProjectExplorer::BuildSystemTask{ProjectExplorer::Task::Warning,
+                                                  tr("Cannot validate this Ninja executable.")};
+    return tasks;
+}
+
+void NinjaToolKitAspect::setup(ProjectExplorer::Kit *k)
+{
+    const auto tool = ninjaTool(k);
+    if (!tool) {
+        const auto autoDetected = MesonTools::ninjaWrapper();
+        if (autoDetected)
+            setNinjaTool(k, autoDetected->id());
+    }
+}
+
+void NinjaToolKitAspect::fix(ProjectExplorer::Kit *k)
+{
+    setup(k);
+}
+
+ProjectExplorer::KitAspect::ItemList NinjaToolKitAspect::toUserOutput(
+    const ProjectExplorer::Kit *k) const
+{
+    const auto tool = ninjaTool(k);
+    if (tool)
+        return {{tr("Ninja"), tool->name()}};
+    return {{tr("Ninja"), tr("Unconfigured")}};
+}
+
+ProjectExplorer::KitAspectWidget *NinjaToolKitAspect::createConfigWidget(ProjectExplorer::Kit *k) const
+{
+    QTC_ASSERT(k, return nullptr);
+    return new ToolKitAspectWidget{k, this, ToolKitAspectWidget::ToolType::Ninja};
+}
+
+void NinjaToolKitAspect::setNinjaTool(ProjectExplorer::Kit *kit, Core::Id id)
+{
+    QTC_ASSERT(kit && id.isValid(), return );
+    kit->setValue(TOOL_ID, id.toSetting());
+}
+
+Core::Id NinjaToolKitAspect::ninjaToolId(const ProjectExplorer::Kit *kit)
+{
+    QTC_ASSERT(kit, return {});
+    return Core::Id::fromSetting(kit->value(TOOL_ID));
+}
+} // namespace Internal
+} // namespace MesonProjectManager