rename PythonEditor plugin to Python

The plugin does not only contain a pure editor, but all kind of support
for a programming language like project and run support.

Change-Id: I1251367c8db2e7a54986415ffc5b860cb210de3c
Reviewed-by: Christian Stenger <christian.stenger@qt.io>

1 files changed, 127 insertions, 0 deletions

diff --git a/src/plugins/python/pythonindenter.cpp b/src/plugins/python/pythonindenter.cpp
new file mode 100644
index 0000000000..dff38907ee
--- /dev/null
+++ b/src/plugins/python/pythonindenter.cpp
@@ -0,0 +1,127 @@
+/****************************************************************************
+**
+** Copyright (C) 2016 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 "pythonindenter.h"
+#include "pythonscanner.h"
+
+#include <texteditor/tabsettings.h>
+
+#include <algorithm>
+
+namespace Python {
+
+static bool isEmptyLine(const QString &t)
+{
+    return std::all_of(t.cbegin(), t.cend(), [] (QChar c) { return c.isSpace(); });
+}
+
+static inline bool isEmptyLine(const QTextBlock &block)
+{
+    return isEmptyLine(block.text());
+}
+
+static QTextBlock previousNonEmptyBlock(const QTextBlock &block)
+{
+    QTextBlock result = block;
+    while (result.isValid() && isEmptyLine(result))
+        result = result.previous();
+    return result;
+}
+
+PythonIndenter::PythonIndenter(QTextDocument *doc)
+    : TextEditor::TextIndenter(doc)
+{}
+
+/**
+ * @brief Does given character change indentation level?
+ * @param ch Any value
+ * @return True if character increases indentation level at the next line
+ */
+bool PythonIndenter::isElectricCharacter(const QChar &ch) const
+{
+    return ch == ':';
+}
+
+int PythonIndenter::indentFor(const QTextBlock &block,
+                              const TextEditor::TabSettings &tabSettings,
+                              int /*cursorPositionInEditor*/)
+{
+    QTextBlock previousBlock = block.previous();
+    if (!previousBlock.isValid())
+        return 0;
+
+    // When pasting in actual code, try to skip back past empty lines to an
+    // actual code line to find a suitable indentation. This prevents code from
+    // not being indented when pasting below an empty line.
+    if (!isEmptyLine(block)) {
+        const QTextBlock previousNonEmpty = previousNonEmptyBlock(previousBlock);
+        if (previousNonEmpty.isValid())
+            previousBlock = previousNonEmpty;
+    }
+
+    QString previousLine = previousBlock.text();
+    int indentation = tabSettings.indentationColumn(previousLine);
+
+    if (isElectricLine(previousLine))
+        indentation += tabSettings.m_indentSize;
+    else
+        indentation = qMax<int>(0, indentation + getIndentDiff(previousLine, tabSettings));
+
+    return indentation;
+}
+
+/// @return True if electric character is last non-space character at given string
+bool PythonIndenter::isElectricLine(const QString &line) const
+{
+    if (line.isEmpty())
+        return false;
+
+    // trim spaces in 'if True:  '
+    int index = line.length() - 1;
+    while (index > 0 && line[index].isSpace())
+        --index;
+
+    return isElectricCharacter(line[index]);
+}
+
+/// @return negative indent diff if previous line breaks control flow branch
+int PythonIndenter::getIndentDiff(const QString &previousLine,
+                                  const TextEditor::TabSettings &tabSettings) const
+{
+    static const QStringList jumpKeywords = {
+        "return", "yield", "break", "continue", "raise", "pass" };
+
+    Internal::Scanner sc(previousLine.constData(), previousLine.length());
+    forever {
+        Internal::FormatToken tk = sc.read();
+        if (tk.format() == Internal::Format_Keyword && jumpKeywords.contains(sc.value(tk)))
+            return -tabSettings.m_indentSize;
+        if (tk.format() != Internal::Format_Whitespace)
+            break;
+    }
+    return 0;
+}
+
+} // namespace Python