ClangFormat: Refactor indenter to allow ClangFormat unit-tests

We do not build texteditor files in unit-tests so some tricks
were required to make ClangFormatIndenter available.

First simple unit-test proofs it builds and runs.

Change-Id: I81d5ea099bd27fd1c1ed8b5b7877299dcc62a67f
Reviewed-by: Nikolai Kosjar <nikolai.kosjar@qt.io>

src/plugins/clangformat/clangformatbaseindenter.h

@@ -0,0 +1,75 @@
+/****************************************************************************
+**
+** Copyright (C) 2019 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 <texteditor/indenter.h>
+
+#include <clang/Format/Format.h>
+
+namespace ClangFormat {
+
+class ClangFormatBaseIndenter : public TextEditor::Indenter
+{
+public:
+    ClangFormatBaseIndenter(QTextDocument *doc);
+
+    TextEditor::IndentationForBlock indentationForBlocks(
+        const QVector<QTextBlock> &blocks, const TextEditor::TabSettings & /*tabSettings*/) override;
+    void indent(const QTextCursor &cursor,
+                const QChar &typedChar,
+                const TextEditor::TabSettings & /*tabSettings*/) override;
+
+    void reindent(const QTextCursor &cursor,
+                  const TextEditor::TabSettings & /*tabSettings*/) override;
+
+    TextEditor::Replacements format(const QTextCursor &cursor,
+                                    const TextEditor::TabSettings & /*tabSettings*/) override;
+
+    void indentBlock(const QTextBlock &block,
+                     const QChar &typedChar,
+                     const TextEditor::TabSettings & /*tabSettings*/) override;
+
+    int indentFor(const QTextBlock &block, const TextEditor::TabSettings & /*tabSettings*/) override;
+
+    bool isElectricCharacter(const QChar &ch) const override;
+
+protected:
+    virtual clang::format::FormatStyle styleForFile() const;
+
+private:
+    void indent(const QTextCursor &cursor, const QChar &typedChar);
+    void indentBlock(const QTextBlock &block, const QChar &typedChar);
+    int indentFor(const QTextBlock &block);
+    TextEditor::Replacements replacements(QByteArray buffer,
+                                          int utf8Offset,
+                                          int utf8Length,
+                                          const QTextBlock &block,
+                                          const QChar &typedChar = QChar::Null,
+                                          bool onlyIndention = true,
+                                          bool secondTry = false) const;
+};
+
+} // namespace ClangFormat