Clang: Add SymbolQuery

Change-Id: I5cb81dffd6f1fda6bdcba0eedaf79f0bc91348b5
Reviewed-by: Tim Jenssen <tim.jenssen@qt.io>

src/plugins/clangrefactoring/symbolquery.h

@@ -0,0 +1,110 @@
+/****************************************************************************
+**
+** Copyright (C) 2017 The Qt Company Ltd.
+** 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.
+**
+****************************************************************************/
+
+#pragma once
+
+#include <utils/smallstring.h>
+
+#include <sourcelocations.h>
+
+#include <algorithm>
+
+namespace ClangRefactoring {
+
+template <typename StatementFactory>
+class SymbolQuery
+{
+    using ReadStatement = typename StatementFactory::ReadStatementType;
+
+public:
+    using Location = SourceLocations::Location;
+    using Source = SourceLocations::Source;
+
+    SymbolQuery(StatementFactory &statementFactory)
+        : m_statementFactory(statementFactory)
+    {}
+
+    SourceLocations locationsAt(const Utils::PathString &filePath, uint line, uint utf8Column)
+    {
+        ReadStatement &locationsStatement = m_statementFactory.selectLocationsForSymbolLocation;
+
+        const std::size_t reserveSize = 128;
+
+        auto locations = locationsStatement.template structValues<Location, qint64, qint64, qint64>(
+                    reserveSize,
+                    filePath,
+                    line,
+                    utf8Column);
+
+        const std::vector<qint64> sourceIds = uniqueSourceIds(locations);
+
+        ReadStatement &sourcesStatement = m_statementFactory.selectSourcePathForId;
+
+        auto sources = sourcesStatement.template structValues<Source, qint64, Utils::PathString>(
+                    reserveSize,
+                    sourceIds);
+
+        return {locations, sourcesToHashMap(sources)};
+    }
+
+    static
+    qint64 sourceId(const Location &location)
+    {
+        return location.sourceId;
+    }
+
+    static
+    std::vector<qint64> uniqueSourceIds(const std::vector<Location> &locations)
+    {
+        std::vector<qint64> ids;
+        ids.reserve(locations.size());
+
+        std::transform(locations.begin(),
+                       locations.end(),
+                       std::back_inserter(ids),
+                       sourceId);
+
+        auto newEnd = std::unique(ids.begin(), ids.end());
+        ids.erase(newEnd, ids.end());
+
+        return ids;
+    }
+
+    static
+    std::unordered_map<qint64, Utils::PathString> sourcesToHashMap(const std::vector<Source> &sources)
+    {
+        std::unordered_map<qint64, Utils::PathString> dictonary;
+
+        for (const Source &source : sources)
+            dictonary.emplace(source.sourceId, std::move(source.sourcePath));
+
+        return dictonary;
+    }
+
+private:
+    StatementFactory &m_statementFactory;
+};
+
+} // namespace ClangRefactoring