Clang: Provide highlighting for identifier under cursor

Change-Id: I80ffe23cbcc84ab7323124581d9dd6afbe974fd0
Reviewed-by: Marco Bubke <marco.bubke@qt.io>

src/tools/clangbackend/ipcsource/clangrequestreferencesjob.cpp

@@ -0,0 +1,83 @@
+/****************************************************************************
+**
+** 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.
+**
+****************************************************************************/
+
+#include "clangrequestreferencesjob.h"
+
+#include <clangbackendipc/clangbackendipcdebugutils.h>
+#include <clangbackendipc/referencesmessage.h>
+#include <clangbackendipc/clangcodemodelclientinterface.h>
+
+#include <utils/qtcassert.h>
+
+namespace ClangBackEnd {
+
+static RequestReferencesJob::AsyncResult runAsyncHelper(const TranslationUnit &translationUnit,
+                                                        quint32 line,
+                                                        quint32 column)
+{
+    TIME_SCOPE_DURATION("RequestReferencesJobRunner");
+
+    return translationUnit.references(line, column);
+}
+
+IAsyncJob::AsyncPrepareResult RequestReferencesJob::prepareAsyncRun()
+{
+    const JobRequest jobRequest = context().jobRequest;
+    QTC_ASSERT(jobRequest.type == JobRequest::Type::RequestReferences,
+               return AsyncPrepareResult());
+
+    try {
+        m_pinnedDocument = context().documentForJobRequest();
+        m_pinnedFileContainer = m_pinnedDocument.fileContainer();
+
+        const TranslationUnit translationUnit
+                = m_pinnedDocument.translationUnit(jobRequest.preferredTranslationUnit);
+        const quint32 line = jobRequest.line;
+        const quint32 column = jobRequest.column;
+        setRunner([translationUnit, line, column]() {
+            return runAsyncHelper(translationUnit, line, column);
+        });
+        return AsyncPrepareResult{translationUnit.id()};
+
+    } catch (const std::exception &exception) {
+        qWarning() << "Error in RequestReferencesJob::prepareAsyncRun:" << exception.what();
+        return AsyncPrepareResult();
+    }
+}
+
+void RequestReferencesJob::finalizeAsyncRun()
+{
+    if (!context().isOutdated()) {
+        const AsyncResult result = asyncResult();
+
+        const ReferencesMessage message(m_pinnedFileContainer,
+                                        result.references,
+                                        result.isLocalVariable,
+                                        context().jobRequest.ticketNumber);
+        context().client->references(message);
+    }
+}
+
+} // namespace ClangBackEnd