Clang: Add revision and completion management

Reparsing a document is expensive so we should avoid it by all means. In
this patch we prevent that the same document is send again. It isn't send
too in advance of a code completion if there was no changes before the
the completion position.

Change-Id: I0bb786ba1d4e7ce08611a518cb32f8cf8f4d0037
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@theqtcompany.com>

1 files changed, 89 insertions, 0 deletions

diff --git a/src/plugins/cpptools/senddocumenttracker.cpp b/src/plugins/cpptools/senddocumenttracker.cpp
new file mode 100644
index 0000000000..d594d1d82d
--- /dev/null
+++ b/src/plugins/cpptools/senddocumenttracker.cpp
@@ -0,0 +1,89 @@
+/****************************************************************************
+**
+** Copyright (C) 2015 The Qt Company Ltd.
+** Contact: http://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 http://www.qt.io/terms-conditions.  For further information
+** use the contact form at http://www.qt.io/contact-us.
+**
+** GNU Lesser General Public License Usage
+** Alternatively, this file may be used under the terms of the GNU Lesser
+** General Public License version 2.1 or version 3 as published by the Free
+** Software Foundation and appearing in the file LICENSE.LGPLv21 and
+** LICENSE.LGPLv3 included in the packaging of this file.  Please review the
+** following information to ensure the GNU Lesser General Public License
+** requirements will be met: https://www.gnu.org/licenses/lgpl.html and
+** http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** In addition, as a special exception, The Qt Company gives you certain additional
+** rights.  These rights are described in The Qt Company LGPL Exception
+** version 1.1, included in the file LGPL_EXCEPTION.txt in this package.
+**
+****************************************************************************/
+
+#include "senddocumenttracker.h"
+
+#include <algorithm>
+
+namespace CppTools {
+
+void SendDocumentTracker::setLastSentRevision(int revision)
+{
+    m_lastSentRevision = revision;
+    m_contentChangeStartPosition = std::numeric_limits<int>::max();
+}
+
+int SendDocumentTracker::lastSentRevision() const
+{
+    return m_lastSentRevision;
+}
+
+void SendDocumentTracker::setLastCompletionPosition(int lastCompletionPosition)
+{
+    m_lastCompletionPosition = lastCompletionPosition;
+}
+
+int SendDocumentTracker::lastCompletionPosition() const
+{
+    return m_lastCompletionPosition;
+}
+
+void SendDocumentTracker::applyContentChange(int startPosition)
+{
+    if (startPosition < m_lastCompletionPosition)
+        m_lastCompletionPosition = -1;
+
+    m_contentChangeStartPosition = std::min(startPosition, m_contentChangeStartPosition);
+}
+
+bool SendDocumentTracker::shouldSendCompletion(int newCompletionPosition) const
+{
+    return m_lastCompletionPosition != newCompletionPosition;
+}
+
+bool SendDocumentTracker::shouldSendRevision(uint newRevision) const
+{
+    return m_lastSentRevision != int(newRevision);
+}
+
+bool SendDocumentTracker::shouldSendRevisionWithCompletionPosition(int newRevision, int newCompletionPosition) const
+{
+    if (shouldSendRevision(newRevision))
+        return changedBeforeCompletionPosition(newCompletionPosition);
+
+    return false;
+}
+
+bool SendDocumentTracker::changedBeforeCompletionPosition(int newCompletionPosition) const
+{
+    return m_contentChangeStartPosition < newCompletionPosition;
+}
+
+} // namespace CppTools