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/project/ninjabuildstep.cpp

@@ -0,0 +1,186 @@
+/****************************************************************************
+**
+** 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 "ninjabuildstep.h"
+#include "buildoptions/mesonbuildstepconfigwidget.h"
+#include "outputparsers/mesonoutputparser.h"
+#include "mesonbuildconfiguration.h"
+#include "mesonbuildsystem.h"
+#include "mesonpluginconstants.h"
+#include <settings/general/settings.h>
+#include <settings/tools/kitaspect/ninjatoolkitaspect.h>
+#include <coreplugin/id.h>
+#include <projectexplorer/buildconfiguration.h>
+#include <projectexplorer/buildsteplist.h>
+#include <projectexplorer/processparameters.h>
+#include <projectexplorer/projectexplorerconstants.h>
+#include <projectexplorer/target.h>
+
+namespace MesonProjectManager {
+namespace Internal {
+const char TARGETS_KEY[] = "MesonProjectManager.BuildStep.BuildTargets";
+const char TOOL_ARGUMENTS_KEY[] = "MesonProjectManager.BuildStep.AdditionalArguments";
+
+NinjaBuildStep::NinjaBuildStep(ProjectExplorer::BuildStepList *bsl, Core::Id id)
+    : ProjectExplorer::AbstractProcessStep{bsl, id}
+{
+    setDefaultDisplayName(tr("Meson Build"));
+    if (m_targetName.isEmpty())
+        setBuildTarget(defaultBuildTarget());
+    setLowPriority();
+    connect(target(), &ProjectExplorer::Target::parsingFinished, this, &NinjaBuildStep::update);
+    connect(Settings::instance(),
+            &Settings::verboseNinjaChanged,
+            this,
+            &NinjaBuildStep::commandChanged);
+}
+
+ProjectExplorer::BuildStepConfigWidget *NinjaBuildStep::createConfigWidget()
+{
+    return new MesonBuildStepConfigWidget{this};
+}
+
+// --verbose is only supported since
+// https://github.com/ninja-build/ninja/commit/bf7517505ad1def03e13bec2b4131399331bc5c4
+// TODO check when to switch back to --verbose
+Utils::CommandLine NinjaBuildStep::command()
+{
+    Utils::CommandLine cmd = [this] {
+        auto tool = NinjaToolKitAspect::ninjaTool(target()->kit());
+        if (tool)
+            return Utils::CommandLine{tool->exe()};
+        return Utils::CommandLine{};
+    }();
+    if (!m_commandArgs.isEmpty())
+        cmd.addArgs(m_commandArgs, Utils::CommandLine::RawType::Raw);
+    if (Settings::verboseNinja())
+        cmd.addArg("-v");
+    cmd.addArg(m_targetName);
+    return cmd;
+}
+
+QStringList NinjaBuildStep::projectTargets()
+{
+    return static_cast<MesonBuildSystem *>(buildSystem())->targetList();
+}
+
+void NinjaBuildStep::update(bool parsingSuccessful)
+{
+    if (parsingSuccessful) {
+        if (!projectTargets().contains(m_targetName)) {
+            m_targetName = defaultBuildTarget();
+        }
+        emit targetListChanged();
+    }
+}
+
+bool NinjaBuildStep::init()
+{
+    // TODO check if the setup is ok
+    MesonBuildConfiguration *bc = static_cast<MesonBuildConfiguration *>(buildConfiguration());
+    ProjectExplorer::ProcessParameters *pp = processParameters();
+    pp->setMacroExpander(bc->macroExpander());
+    Utils::Environment env = bc->environment();
+    Utils::Environment::setupEnglishOutput(&env);
+    pp->setEnvironment(env);
+    pp->setWorkingDirectory(bc->buildDirectory());
+    pp->setCommandLine(command());
+    pp->resolveAll();
+
+    return AbstractProcessStep::init();
+}
+
+QString NinjaBuildStep::defaultBuildTarget() const
+{
+    const ProjectExplorer::BuildStepList *const bsl = stepList();
+    QTC_ASSERT(bsl, return {});
+    const Core::Id parentId = bsl->id();
+    if (parentId == ProjectExplorer::Constants::BUILDSTEPS_CLEAN)
+        return Constants::Targets::clean;
+    if (parentId == ProjectExplorer::Constants::BUILDSTEPS_DEPLOY)
+        return Constants::Targets::install;
+    return Constants::Targets::all;
+}
+
+void NinjaBuildStep::doRun()
+{
+    AbstractProcessStep::doRun();
+}
+
+void NinjaBuildStep::setupOutputFormatter(Utils::OutputFormatter *formatter)
+{
+    auto mesonOutputParser = new MesonOutputParser;
+    mesonOutputParser->setSourceDirectory(project()->projectDirectory());
+    formatter->addLineParser(mesonOutputParser);
+    m_ninjaParser = new NinjaParser;
+    m_ninjaParser->setSourceDirectory(project()->projectDirectory());
+    formatter->addLineParser(m_ninjaParser);
+    auto additionalParsers = target()->kit()->createOutputParsers();
+    std::for_each(std::cbegin(additionalParsers),
+                  std::cend(additionalParsers),
+                  [this](const auto parser) { parser->setRedirectionDetector(m_ninjaParser); });
+    formatter->addLineParsers(additionalParsers);
+    formatter->addSearchDir(processParameters()->effectiveWorkingDirectory());
+    AbstractProcessStep::setupOutputFormatter(formatter);
+
+    connect(m_ninjaParser, &NinjaParser::reportProgress, this, [this](int percent) {
+        emit progress(percent, QString());
+    });
+}
+
+MesonBuildStepFactory::MesonBuildStepFactory()
+{
+    registerStep<NinjaBuildStep>(Constants::MESON_BUILD_STEP_ID);
+    setSupportedProjectType(Constants::Project::ID);
+    setDisplayName(NinjaBuildStep::tr("Meson"));
+}
+
+void MesonProjectManager::Internal::NinjaBuildStep::setBuildTarget(const QString &targetName)
+{
+    m_targetName = targetName;
+}
+
+void NinjaBuildStep::setCommandArgs(const QString &args)
+{
+    m_commandArgs = args.trimmed();
+}
+
+QVariantMap NinjaBuildStep::toMap() const
+{
+    QVariantMap map(AbstractProcessStep::toMap());
+    map.insert(TARGETS_KEY, m_targetName);
+    map.insert(TOOL_ARGUMENTS_KEY, m_commandArgs);
+    return map;
+}
+
+bool NinjaBuildStep::fromMap(const QVariantMap &map)
+{
+    m_targetName = map.value(TARGETS_KEY).toString();
+    m_commandArgs = map.value(TOOL_ARGUMENTS_KEY).toString();
+    return AbstractProcessStep::fromMap(map);
+}
+
+} // namespace Internal
+} // namespace MesonProjectManager