1. use consistenly the 'override' keyword

2. added some documentation for clang-tidy

admin/README.clang-tidy

+http://clang.llvm.org/extra/clang-tidy/
+
+To use clang-tidy:
+* add -DCMAKE_EXPORT_COMPILE_COMMANDS=ON to cmake (for example in compile-clang)
+* cd src && ln -s ../build-clang/compile_commands.json compile_commands.json
+* execute clang-tidy
+
+
+To list all available checks:
+* clang-tidy --list-checks -checks='*' | grep "modernize"
+
+E.g., use override for virtual funcsion:
+* clang-tidy my_file.cpp -checks='modernize-use-override'
+
+clan-tidy can also execute clang-analyzer checks, e.g.
+* clang-tidy my_file.cpp -checks=-*,clang-analyzer-*,-clang-analyzer-cplusplus*
+
+To apply the fixes direcly on the file, add 'fix' parameter:
+* clang-tidy.py my_file.cpp -header-filter='.*' -checks='-*,modernize-use-nullptr' -fix
+
+run-clang-tidy.py -header-filter='.*' -checks='-*,modernize-use-nullptr' -fix
+run-clang-tidy.py -header-filter='.*' -checks='-*,modernize-use-override' -fix
+
+
+https://github.com/llvm-mirror/clang-tools-extra/blob/master/clang-tidy/tool/run-clang-tidy.py

admin/run-clang-tidy.py

+#!/usr/bin/env python
+#
+#===- run-clang-tidy.py - Parallel clang-tidy runner ---------*- python -*--===#
+#
+#                     The LLVM Compiler Infrastructure
+#
+# This file is distributed under the University of Illinois Open Source
+# License. See LICENSE.TXT for details.
+#
+#===------------------------------------------------------------------------===#
+# FIXME: Integrate with clang-tidy-diff.py
+
+"""
+Parallel clang-tidy runner
+==========================
+
+Runs clang-tidy over all files in a compilation database. Requires clang-tidy
+and clang-apply-replacements in $PATH.
+
+Example invocations.
+- Run clang-tidy on all files in the current working directory with a default
+  set of checks and show warnings in the cpp files and all project headers.
+    run-clang-tidy.py $PWD
+
+- Fix all header guards.
+    run-clang-tidy.py -fix -checks=-*,llvm-header-guard
+
+- Fix all header guards included from clang-tidy and header guards
+  for clang-tidy headers.
+    run-clang-tidy.py -fix -checks=-*,llvm-header-guard extra/clang-tidy \
+                      -header-filter=extra/clang-tidy
+
+Compilation database setup:
+http://clang.llvm.org/docs/HowToSetupToolingForLLVM.html
+"""
+
+from __future__ import print_function
+
+import argparse
+import glob
+import json
+import multiprocessing
+import os
+import re
+import shutil
+import subprocess
+import sys
+import tempfile
+import threading
+import traceback
+import yaml
+
+is_py2 = sys.version[0] == '2'
+
+if is_py2:
+    import Queue as queue
+else:
+    import queue as queue
+
+def find_compilation_database(path):
+  """Adjusts the directory until a compilation database is found."""
+  result = './'
+  while not os.path.isfile(os.path.join(result, path)):
+    if os.path.realpath(result) == '/':
+      print('Error: could not find compilation database.')
+      sys.exit(1)
+    result += '../'
+  return os.path.realpath(result)
+
+
+def make_absolute(f, directory):
+  if os.path.isabs(f):
+    return f
+  return os.path.normpath(os.path.join(directory, f))
+
+
+def get_tidy_invocation(f, clang_tidy_binary, checks, tmpdir, build_path,
+                        header_filter, extra_arg, extra_arg_before, quiet):
+  """Gets a command line for clang-tidy."""
+  start = [clang_tidy_binary]
+  if header_filter is not None:
+    start.append('-header-filter=' + header_filter)
+  else:
+    # Show warnings in all in-project headers by default.
+    start.append('-header-filter=^' + build_path + '/.*')
+  if checks:
+    start.append('-checks=' + checks)
+  if tmpdir is not None:
+    start.append('-export-fixes')
+    # Get a temporary file. We immediately close the handle so clang-tidy can
+    # overwrite it.
+    (handle, name) = tempfile.mkstemp(suffix='.yaml', dir=tmpdir)
+    os.close(handle)
+    start.append(name)
+  for arg in extra_arg:
+      start.append('-extra-arg=%s' % arg)
+  for arg in extra_arg_before:
+      start.append('-extra-arg-before=%s' % arg)
+  start.append('-p=' + build_path)
+  if quiet:
+      start.append('-quiet')
+  start.append(f)
+  return start
+
+
+def merge_replacement_files(tmpdir, mergefile):
+  """Merge all replacement files in a directory into a single file"""
+  # The fixes suggested by clang-tidy >= 4.0.0 are given under
+  # the top level key 'Diagnostics' in the output yaml files
+  mergekey="Diagnostics"
+  merged=[]
+  for replacefile in glob.iglob(os.path.join(tmpdir, '*.yaml')):
+    content = yaml.safe_load(open(replacefile, 'r'))
+    if not content:
+      continue # Skip empty files.
+    merged.extend(content.get(mergekey, []))
+
+  if merged:
+    # MainSourceFile: The key is required by the definition inside
+    # include/clang/Tooling/ReplacementsYaml.h, but the value
+    # is actually never used inside clang-apply-replacements,
+    # so we set it to '' here.
+    output = { 'MainSourceFile': '', mergekey: merged }
+    with open(mergefile, 'w') as out:
+      yaml.safe_dump(output, out)
+  else:
+    # Empty the file:
+    open(mergefile, 'w').close()
+
+
+def check_clang_apply_replacements_binary(args):
+  """Checks if invoking supplied clang-apply-replacements binary works."""
+  try:
+    subprocess.check_call([args.clang_apply_replacements_binary, '--version'])
+  except:
+    print('Unable to run clang-apply-replacements. Is clang-apply-replacements '
+          'binary correctly specified?', file=sys.stderr)
+    traceback.print_exc()
+    sys.exit(1)
+
+
+def apply_fixes(args, tmpdir):
+  """Calls clang-apply-fixes on a given directory."""
+  invocation = [args.clang_apply_replacements_binary]
+  if args.format:
+    invocation.append('-format')
+  if args.style:
+    invocation.append('-style=' + args.style)
+  invocation.append(tmpdir)
+  subprocess.call(invocation)
+
+
+def run_tidy(args, tmpdir, build_path, queue):
+  """Takes filenames out of queue and runs clang-tidy on them."""
+  while True:
+    name = queue.get()
+    invocation = get_tidy_invocation(name, args.clang_tidy_binary, args.checks,
+                                     tmpdir, build_path, args.header_filter,
+                                     args.extra_arg, args.extra_arg_before,
+                                     args.quiet)
+    sys.stdout.write(' '.join(invocation) + '\n')
+    subprocess.call(invocation)
+    queue.task_done()
+
+
+def main():
+  parser = argparse.ArgumentParser(description='Runs clang-tidy over all files '
+                                   'in a compilation database. Requires '
+                                   'clang-tidy and clang-apply-replacements in '
+                                   '$PATH.')
+  parser.add_argument('-clang-tidy-binary', metavar='PATH',
+                      default='clang-tidy',
+                      help='path to clang-tidy binary')
+  parser.add_argument('-clang-apply-replacements-binary', metavar='PATH',
+                      default='clang-apply-replacements',
+                      help='path to clang-apply-replacements binary')
+  parser.add_argument('-checks', default=None,
+                      help='checks filter, when not specified, use clang-tidy '
+                      'default')
+  parser.add_argument('-header-filter', default=None,
+                      help='regular expression matching the names of the '
+                      'headers to output diagnostics from. Diagnostics from '
+                      'the main file of each translation unit are always '
+                      'displayed.')
+  parser.add_argument('-export-fixes', metavar='filename', dest='export_fixes',
+                      help='Create a yaml file to store suggested fixes in, '
+                      'which can be applied with clang-apply-replacements.')
+  parser.add_argument('-j', type=int, default=0,
+                      help='number of tidy instances to be run in parallel.')
+  parser.add_argument('files', nargs='*', default=['.*'],
+                      help='files to be processed (regex on path)')
+  parser.add_argument('-fix', action='store_true', help='apply fix-its')
+  parser.add_argument('-format', action='store_true', help='Reformat code '
+                      'after applying fixes')
+  parser.add_argument('-style', default='file', help='The style of reformat '
+                      'code after applying fixes')
+  parser.add_argument('-p', dest='build_path',
+                      help='Path used to read a compile command database.')
+  parser.add_argument('-extra-arg', dest='extra_arg',
+                      action='append', default=[],
+                      help='Additional argument to append to the compiler '
+                      'command line.')
+  parser.add_argument('-extra-arg-before', dest='extra_arg_before',
+                      action='append', default=[],
+                      help='Additional argument to prepend to the compiler '
+                      'command line.')
+  parser.add_argument('-quiet', action='store_true',
+                      help='Run clang-tidy in quiet mode')
+  args = parser.parse_args()
+
+  db_path = 'compile_commands.json'
+
+  if args.build_path is not None:
+    build_path = args.build_path
+  else:
+    # Find our database
+    build_path = find_compilation_database(db_path)
+
+  try:
+    invocation = [args.clang_tidy_binary, '-list-checks']
+    invocation.append('-p=' + build_path)
+    if args.checks:
+      invocation.append('-checks=' + args.checks)
+    invocation.append('-')
+    print(subprocess.check_output(invocation))
+  except:
+    print("Unable to run clang-tidy.", file=sys.stderr)
+    sys.exit(1)
+
+  # Load the database and extract all files.
+  database = json.load(open(os.path.join(build_path, db_path)))
+  files = [make_absolute(entry['file'], entry['directory'])
+           for entry in database]
+
+  max_task = args.j
+  if max_task == 0:
+    max_task = multiprocessing.cpu_count()
+
+  tmpdir = None
+  if args.fix or args.export_fixes:
+    check_clang_apply_replacements_binary(args)
+    tmpdir = tempfile.mkdtemp()
+
+  # Build up a big regexy filter from all command line arguments.
+  file_name_re = re.compile('|'.join(args.files))
+
+  try:
+    # Spin up a bunch of tidy-launching threads.
+    task_queue = queue.Queue(max_task)
+    for _ in range(max_task):
+      t = threading.Thread(target=run_tidy,
+                           args=(args, tmpdir, build_path, task_queue))
+      t.daemon = True
+      t.start()
+
+    # Fill the queue with files.
+    for name in files:
+      if file_name_re.search(name):
+        task_queue.put(name)
+
+    # Wait for all threads to be done.
+    task_queue.join()
+
+  except KeyboardInterrupt:
+    # This is a sad hack. Unfortunately subprocess goes
+    # bonkers with ctrl-c and we start forking merrily.
+    print('\nCtrl-C detected, goodbye.')
+    if tmpdir:
+      shutil.rmtree(tmpdir)
+    os.kill(0, 9)
+
+  return_code = 0
+  if args.export_fixes:
+    print('Writing fixes to ' + args.export_fixes + ' ...')
+    try:
+      merge_replacement_files(tmpdir, args.export_fixes)
+    except:
+      print('Error exporting fixes.\n', file=sys.stderr)
+      traceback.print_exc()
+      return_code=1
+
+  if args.fix:
+    print('Applying fixes ...')
+    try:
+      apply_fixes(args, tmpdir)
+    except:
+      print('Error applying fixes.\n', file=sys.stderr)
+      traceback.print_exc()
+      return_code=1
+
+  if tmpdir:
+    shutil.rmtree(tmpdir)
+  sys.exit(return_code)
+
+if __name__ == '__main__':
+  main()
+

src/backend/cantorWorksheet/CantorWorksheet.h

@@ -51,16 +51,16 @@ class CantorWorksheet : public AbstractPart, public scripted {
 public:
 	CantorWorksheet(AbstractScriptingEngine* engine, const QString& name, bool loading = false);
 
-	virtual QWidget* view() const override;
-	virtual QMenu* createContextMenu() override;
-	virtual QIcon icon() const override;
+	QWidget* view() const override;
+	QMenu* createContextMenu() override;
+	QIcon icon() const override;
 
-	virtual bool exportView() const override;
-	virtual bool printView() override;
-	virtual bool printPreview() const override;
+	bool exportView() const override;
+	bool printView() override;
+	bool printPreview() const override;
 
-	virtual void save(QXmlStreamWriter*) const override;
-	virtual bool load(XmlStreamReader*, bool preview) override;
+	void save(QXmlStreamWriter*) const override;
+	bool load(XmlStreamReader*, bool preview) override;
 
 	QString backendName();
 	KParts::ReadWritePart* part();

src/backend/core/AbstractAspect.h

@@ -60,7 +60,7 @@ public:
 	friend class AbstractAspectPrivate;
 
 	explicit AbstractAspect(const QString& name);
-	virtual ~AbstractAspect();
+	~AbstractAspect() override;
 
 	QString name() const;
 	QString comment() const;

src/backend/core/AbstractColumn.h

@@ -128,7 +128,7 @@ public:
 	};
 
 	explicit AbstractColumn(const QString& name);
-	virtual ~AbstractColumn();
+	~AbstractColumn() override;
 
 	static QStringList dateFormats();	// supported date formats
 	static QStringList timeFormats();	// supported time formats

src/backend/core/AbstractFilter.h

@@ -39,7 +39,7 @@ class AbstractFilter : public AbstractAspect {
 
 public:
 	explicit AbstractFilter(const QString& name) : AbstractAspect(name) {}
-	virtual ~AbstractFilter() {}
+	~AbstractFilter() override {}
 
 	virtual int inputCount() const = 0;
 	virtual int outputCount() const = 0;

src/backend/core/AbstractPart.h

@@ -38,7 +38,7 @@ class AbstractPart : public AbstractAspect {
 
 	public:
 		explicit AbstractPart(const QString &name);
-		virtual ~AbstractPart();
+		~AbstractPart() override;
 
 		virtual QWidget* view() const = 0;
 		void deleteView() const;
@@ -47,7 +47,7 @@ class AbstractPart : public AbstractAspect {
 		bool hasMdiSubWindow() const;
 		void deleteMdiSubWindow();
 
-		virtual QMenu* createContextMenu();
+		QMenu* createContextMenu() override;
         virtual bool exportView() const = 0;
         virtual bool printView() = 0;
         virtual bool printPreview() const = 0;

src/backend/core/AbstractScript.h

@@ -43,7 +43,7 @@ class AbstractScript : public QObject
 
   public:
     AbstractScript(AbstractScriptingEngine *env, const QString &code, QObject *context=0, const QString &name="<input>");
-    ~AbstractScript();
+    ~AbstractScript() override;
 
     const QString code() const;
     const QObject* context() const;

src/backend/core/AbstractSimpleFilter.h

@@ -41,10 +41,10 @@ class AbstractSimpleFilter : public AbstractFilter {
 
 public:
 	AbstractSimpleFilter();
-	virtual int inputCount() const override;
-	virtual int outputCount() const override;
-	virtual AbstractColumn* output(int port) override;
-	virtual const AbstractColumn * output(int port) const override;
+	int inputCount() const override;
+	int outputCount() const override;
+	AbstractColumn* output(int port) override;
+	const AbstractColumn * output(int port) const override;
 	virtual AbstractColumn::PlotDesignation plotDesignation() const;
 	virtual AbstractColumn::ColumnMode columnMode() const;
 	virtual QString textAt(int row) const;
@@ -57,8 +57,8 @@ public:
 	virtual int rowCount() const;
 	virtual QList<Interval<int>> dependentRows(Interval<int> inputRange) const;
 
-	virtual void save(QXmlStreamWriter*) const override;
-	virtual bool load(XmlStreamReader*, bool preview) override;
+	void save(QXmlStreamWriter*) const override;
+	bool load(XmlStreamReader*, bool preview) override;
 	virtual void writeExtraAttributes(QXmlStreamWriter*) const;
 
 signals:
@@ -66,17 +66,17 @@ signals:
 	void digitsChanged();
 
 protected:
-	virtual void inputPlotDesignationAboutToChange(const AbstractColumn*) override;
-	virtual void inputPlotDesignationChanged(const AbstractColumn*) override;
-	virtual void inputModeAboutToChange(const AbstractColumn*) override;
-	virtual void inputModeChanged(const AbstractColumn*) override;
-	virtual void inputDataAboutToChange(const AbstractColumn*) override;
-	virtual void inputDataChanged(const AbstractColumn*) override;
-
-	virtual void inputRowsAboutToBeInserted(const AbstractColumn * source, int before, int count) override;
-	virtual void inputRowsInserted(const AbstractColumn * source, int before, int count) override;
-	virtual void inputRowsAboutToBeRemoved(const AbstractColumn * source, int first, int count) override;
-	virtual void inputRowsRemoved(const AbstractColumn * source, int first, int count) override;
+	void inputPlotDesignationAboutToChange(const AbstractColumn*) override;
+	void inputPlotDesignationChanged(const AbstractColumn*) override;
+	void inputModeAboutToChange(const AbstractColumn*) override;
+	void inputModeChanged(const AbstractColumn*) override;
+	void inputDataAboutToChange(const AbstractColumn*) override;
+	void inputDataChanged(const AbstractColumn*) override;
+
+	void inputRowsAboutToBeInserted(const AbstractColumn * source, int before, int count) override;
+	void inputRowsInserted(const AbstractColumn * source, int before, int count) override;
+	void inputRowsAboutToBeRemoved(const AbstractColumn * source, int first, int count) override;
+	void inputRowsRemoved(const AbstractColumn * source, int first, int count) override;
 
 	SimpleFilterColumn* m_output_column;
 };
@@ -87,17 +87,17 @@ class SimpleFilterColumn : public AbstractColumn {
 public:
 	SimpleFilterColumn(AbstractSimpleFilter* owner) : AbstractColumn(owner->name()), m_owner(owner) {}
 
-	virtual AbstractColumn::ColumnMode columnMode() const override;
-	virtual int rowCount() const override { return m_owner->rowCount(); }
-	virtual AbstractColumn::PlotDesignation plotDesignation() const override { return m_owner->plotDesignation(); }
-	virtual QString textAt(int row) const override;
-	virtual QDate dateAt(int row) const override;
-	virtual QTime timeAt(int row) const override;
-	virtual QDateTime dateTimeAt(int row) const override;
-	virtual double valueAt(int row) const override;
-	virtual int integerAt(int row) const override;
-	virtual void save(QXmlStreamWriter*) const override {};
-	virtual bool load(XmlStreamReader*, bool preview) override {Q_UNUSED(preview); return true;};
+	AbstractColumn::ColumnMode columnMode() const override;
+	int rowCount() const override { return m_owner->rowCount(); }
+	AbstractColumn::PlotDesignation plotDesignation() const override { return m_owner->plotDesignation(); }
+	QString textAt(int row) const override;
+	QDate dateAt(int row) const override;
+	QTime timeAt(int row) const override;
+	QDateTime dateTimeAt(int row) const override;
+	double valueAt(int row) const override;
+	int integerAt(int row) const override;
+	void save(QXmlStreamWriter*) const override {};
+	bool load(XmlStreamReader*, bool preview) override {Q_UNUSED(preview); return true;};
 private:
 	AbstractSimpleFilter* m_owner;
 

src/backend/core/AspectTreeModel.h

@@ -40,14 +40,14 @@ class AspectTreeModel : public QAbstractItemModel {
 public:
 	explicit AspectTreeModel(AbstractAspect* root, QObject* parent=0);
 
-	QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const;
-	QModelIndex parent(const QModelIndex &index) const;
-	int rowCount(const QModelIndex &parent = QModelIndex()) const;
-	int columnCount(const QModelIndex &parent = QModelIndex()) const;
-	QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const;
-	QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const;
-	bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole);
-	Qt::ItemFlags flags(const QModelIndex &index) const;
+	QModelIndex index(int row, int column, const QModelIndex &parent = QModelIndex()) const override;
+	QModelIndex parent(const QModelIndex &index) const override;
+	int rowCount(const QModelIndex &parent = QModelIndex()) const override;
+	int columnCount(const QModelIndex &parent = QModelIndex()) const override;
+	QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const override;
+	QVariant data(const QModelIndex &index, int role = Qt::DisplayRole) const override;
+	bool setData(const QModelIndex &index, const QVariant &value, int role = Qt::EditRole) override;
+	Qt::ItemFlags flags(const QModelIndex &index) const override;
 	void setSelectableAspects(QList<const char*>);
 	QModelIndex modelIndexOfAspect(const AbstractAspect*, int column=0) const;
 	QModelIndex modelIndexOfAspect(const QString& path, int column=0) const;

src/backend/core/Folder.h

@@ -37,11 +37,11 @@ Q_OBJECT
 public:
 	explicit Folder(const QString& name);
 
-	virtual QIcon icon() const override;
-	virtual QMenu* createContextMenu() override;
+	QIcon icon() const override;
+	QMenu* createContextMenu() override;
 
-	virtual void save(QXmlStreamWriter*) const override;
-	virtual bool load(XmlStreamReader*, bool preview) override;
+	void save(QXmlStreamWriter*) const override;
+	bool load(XmlStreamReader*, bool preview) override;
 
 protected:
 	bool readChildAspectElement(XmlStreamReader*, bool preview);

src/backend/core/Project.h

@@ -48,19 +48,19 @@ public:
 
 public:
 	Project();
-	~Project();
+	~Project() override;
 
 	virtual const Project* project() const {
 		return this;
 	}
-	virtual Project* project() override {
+	Project* project() override {
 		return this;