Meson: Flatten directory hierarchy

Keep tests/ and icons/ but put the rest into the toplevel.

The previous setup was so different from the rest of the bunch that
it regularly stuck out in maintenance tasks.

Change-Id: I69821be6268f69682353a388f6bb1fa343215303
Reviewed-by: Qt CI Bot <qt_ci_bot@qt-project.org>
Reviewed-by: <github-actions-qt-creator@cristianadam.eu>
Reviewed-by: Alessandro Portale <alessandro.portale@qt.io>

src/plugins/mesonprojectmanager/mesonoutputparser.h

@@ -0,0 +1,43 @@
+// Copyright (C) 2020 Alexis Jeandet.
+// SPDX-License-Identifier: LicenseRef-Qt-Commercial OR GPL-3.0+ OR GPL-3.0 WITH Qt-GPL-exception-1.0
+
+#pragma once
+
+#include <projectexplorer/ioutputparser.h>
+
+#include <utils/outputformatter.h>
+
+#include <QRegularExpression>
+
+#include <array>
+
+namespace MesonProjectManager {
+namespace Internal {
+
+class MesonOutputParser final : public ProjectExplorer::OutputTaskParser
+{
+    Q_OBJECT
+    const QRegularExpression m_errorFileLocRegex{R"((^.*meson.build):(\d+):(\d+): ERROR)"};
+    const QRegularExpression m_errorOptionRegex{R"!(ERROR: Value)!"};
+    int m_remainingLines = 0;
+    QStringList m_pending;
+    void pushLine(const QString &line);
+    Result processErrors(const QString &line);
+    Result processWarnings(const QString &line);
+    void addTask(ProjectExplorer::Task::TaskType type, const QString &line);
+    void addTask(ProjectExplorer::Task task);
+    Utils::OutputLineParser::LinkSpecs addTask(ProjectExplorer::Task::TaskType type,
+                                               const QString &line,
+                                               const QRegularExpressionMatch &match,
+                                               int fileCapIndex,
+                                               int lineNumberCapIndex);
+
+public:
+    MesonOutputParser();
+    Result handleLine(const QString &line, Utils::OutputFormat type) override;
+    void readStdo(const QByteArray &data);
+    void setSourceDirectory(const Utils::FilePath &sourceDir);
+};
+
+} // namespace Internal
+} // namespace MesonProjectManager