ClangTools: Fix applying fixits one by one

If a file had multiple fixits and only a subset was applied, the
remaining fixits in that file were invalidated. Fix this by adjusting
the locations of the not yet applied fixits.

Change-Id: I2c190412e871e9011c4d4a62ed938e76ad4cdf72
Reviewed-by: Ivan Donchevskii <ivan.donchevskii@qt.io>

src/plugins/clangtools/clangfixitsrefactoringchanges.h

@@ -0,0 +1,73 @@
+/****************************************************************************
+**
+** Copyright (C) 2018 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/changeset.h>
+#include <utils/textfileformat.h>
+
+#include <QString>
+#include <QTextDocument>
+#include <QVector>
+
+namespace ClangTools {
+namespace Internal {
+
+class ReplacementOperation
+{
+public:
+    int pos = -1;
+    int length = -1;
+    QString text;
+    bool apply = false;
+};
+using ReplacementOperations = QVector<ReplacementOperation *>;
+
+/// Simplified version of TextEditor::RefactoringFile that allows
+/// to operate on not owned ReplamentOperations
+class FixitsRefactoringFile
+{
+public:
+    FixitsRefactoringFile() = default;
+    FixitsRefactoringFile(const QString &filePath) : m_filePath(filePath) {}
+
+    bool isValid() const { return !m_filePath.isEmpty(); }
+    int position(unsigned line, unsigned column) const;
+
+    void setReplacements(const ReplacementOperations &ops) { m_replacementOperations = ops; }
+    bool apply();
+
+private:
+    QTextDocument *document() const;
+    void shiftAffectedReplacements(const ReplacementOperation &op, int startIndex);
+
+    QString m_filePath;
+    mutable Utils::TextFileFormat m_textFileFormat;
+    mutable QTextDocument *m_document = nullptr;
+    ReplacementOperations m_replacementOperations; // Not owned.
+};
+
+} // namespace Internal
+} // namespace ClangTools