1 files changed, 105 insertions, 0 deletions
diff --git a/src/libs/cplusplus/BackwardsScanner.cpp b/src/libs/cplusplus/BackwardsScanner.cpp
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+++ b/src/libs/cplusplus/BackwardsScanner.cpp
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+/**************************************************************************
+**
+** This file is part of Qt Creator
+**
+** Copyright (c) 2009 Nokia Corporation and/or its subsidiary(-ies).
+**
+** Contact: Nokia Corporation (qt-info@nokia.com)
+**
+** Commercial Usage
+**
+** Licensees holding valid Qt Commercial licenses may use this file in
+** accordance with the Qt Commercial License Agreement provided with the
+** Software or, alternatively, in accordance with the terms contained in
+** a written agreement between you and Nokia.
+**
+** 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 as published by the Free Software
+** Foundation and appearing in the file LICENSE.LGPL included in the
+** packaging of this file.  Please review the following information to
+** ensure the GNU Lesser General Public License version 2.1 requirements
+** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html.
+**
+** If you are unsure which license is appropriate for your use, please
+** contact the sales department at http://qt.nokia.com/contact.
+**
+**************************************************************************/
+#include "BackwardsScanner.h"
+#include <QtGui/QTextCursor>
+
+using namespace CPlusPlus;
+
+BackwardsScanner::BackwardsScanner(const QTextCursor &cursor, int maxBlockCount)
+    : _offset(0)
+    , _blocksTokenized(0)
+    , _block(cursor.block())
+    , _maxBlockCount(maxBlockCount)
+{
+    _tokenize.setSkipComments(true);
+    _text = _block.text().left(cursor.position() - cursor.block().position());
+    _tokens.append(_tokenize(_text, previousBlockState(_block)));
+}
+
+QList<SimpleToken> BackwardsScanner::tokens() const
+{ return _tokens; }
+
+const SimpleToken &BackwardsScanner::operator[](int i)
+{
+    while (_offset + i < 0) {
+        _block = _block.previous();
+        if (_blocksTokenized == _maxBlockCount || !_block.isValid()) {
+            ++_offset;
+            _tokens.prepend(SimpleToken()); // sentinel
+            break;
+        } else {
+            ++_blocksTokenized;
+
+            QString blockText = _block.text();
+            _text.prepend(blockText);
+            QList<SimpleToken> adaptedTokens;
+            for (int i = 0; i < _tokens.size(); ++i) {
+                const SimpleToken &t = _tokens.at(i);
+                const int position = t.position() + blockText.length();
+                adaptedTokens.append(SimpleToken(t.kind(),
+                                                 position,
+                                                 t.length(),
+                                                 _text.midRef(position, t.length())));
+            }
+
+            _tokens = _tokenize(blockText, previousBlockState(_block));
+            _offset += _tokens.size();
+            _tokens += adaptedTokens;
+        }
+    }
+
+    return _tokens.at(_offset + i);
+}
+
+int BackwardsScanner::startPosition() const
+{ return _block.position(); }
+
+const QString &BackwardsScanner::text() const
+{ return _text; }
+
+QString BackwardsScanner::text(int begin, int end) const
+{
+    const SimpleToken &firstToken = _tokens.at(begin + _offset);
+    const SimpleToken &lastToken = _tokens.at(end + _offset - 1);
+    return _text.mid(firstToken.begin(), lastToken.end() - firstToken.begin());
+}
+
+int BackwardsScanner::previousBlockState(const QTextBlock &block)
+{
+    const QTextBlock prevBlock = block.previous();
+
+    if (prevBlock.isValid()) {
+        int state = prevBlock.userState();
+
+        if (state != -1)
+            return state;
+    }
+
+    return 0;
+}