clang-tools-extra/clang-tidy/add_new_check.py - llvm-project - Git at Google

 #!/usr/bin/env python
 #
 #===- add_new_check.py - clang-tidy check generator ---------*- python -*--===#
 #
 # Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 # See https://llvm.org/LICENSE.txt for license information.
 # SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 #
 #===-----------------------------------------------------------------------===#

 from __future__ import print_function
 from __future__ import unicode_literals

 import argparse
 import io
 import os
 import re
 import sys

 # Adapts the module's CMakelist file. Returns 'True' if it could add a new
 # entry and 'False' if the entry already existed.
 def adapt_cmake(module_path, check_name_camel):
   filename = os.path.join(module_path, 'CMakeLists.txt')

   # The documentation files are encoded using UTF-8, however on Windows the
   # default encoding might be different (e.g. CP-1252). To make sure UTF-8 is
   # always used, use `io.open(filename, mode, encoding='utf8')` for reading and
   # writing files here and elsewhere.
   with io.open(filename, 'r', encoding='utf8') as f:
     lines = f.readlines()

   cpp_file = check_name_camel + '.cpp'

   # Figure out whether this check already exists.
   for line in lines:
     if line.strip() == cpp_file:
       return False

   print('Updating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     cpp_found = False
     file_added = False
     for line in lines:
       cpp_line = line.strip().endswith('.cpp')
       if (not file_added) and (cpp_line or cpp_found):
         cpp_found = True
         if (line.strip() > cpp_file) or (not cpp_line):
           f.write('  ' + cpp_file + '\n')
           file_added = True
       f.write(line)

   return True


 # Adds a header for the new check.
 def write_header(module_path, module, namespace, check_name, check_name_camel):
   check_name_dashes = module + '-' + check_name
   filename = os.path.join(module_path, check_name_camel) + '.h'
   print('Creating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     header_guard = ('LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_' + module.upper() + '_'
                     + check_name_camel.upper() + '_H')
     f.write('//===--- ')
     f.write(os.path.basename(filename))
     f.write(' - clang-tidy ')
     f.write('-' * max(0, 42 - len(os.path.basename(filename))))
     f.write('*- C++ -*-===//')
     f.write("""
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #ifndef %(header_guard)s
 #define %(header_guard)s

 #include "../ClangTidyCheck.h"

 namespace clang {
 namespace tidy {
 namespace %(namespace)s {

 /// FIXME: Write a short description.
 ///
 /// For the user-facing documentation see:
 /// http://clang.llvm.org/extra/clang-tidy/checks/%(check_name_dashes)s.html
 class %(check_name)s : public ClangTidyCheck {
 public:
   %(check_name)s(StringRef Name, ClangTidyContext *Context)
       : ClangTidyCheck(Name, Context) {}
   void registerMatchers(ast_matchers::MatchFinder *Finder) override;
   void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
 };

 } // namespace %(namespace)s
 } // namespace tidy
 } // namespace clang

 #endif // %(header_guard)s
 """ % {'header_guard': header_guard,
        'check_name': check_name_camel,
        'check_name_dashes': check_name_dashes,
        'module': module,
        'namespace': namespace})


 # Adds the implementation of the new check.
 def write_implementation(module_path, module, namespace, check_name_camel):
   filename = os.path.join(module_path, check_name_camel) + '.cpp'
   print('Creating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     f.write('//===--- ')
     f.write(os.path.basename(filename))
     f.write(' - clang-tidy ')
     f.write('-' * max(0, 51 - len(os.path.basename(filename))))
     f.write('-===//')
     f.write("""
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//

 #include "%(check_name)s.h"
 #include "clang/AST/ASTContext.h"
 #include "clang/ASTMatchers/ASTMatchFinder.h"

 using namespace clang::ast_matchers;

 namespace clang {
 namespace tidy {
 namespace %(namespace)s {

 void %(check_name)s::registerMatchers(MatchFinder *Finder) {
   // FIXME: Add matchers.
   Finder->addMatcher(functionDecl().bind("x"), this);
 }

 void %(check_name)s::check(const MatchFinder::MatchResult &Result) {
   // FIXME: Add callback implementation.
   const auto *MatchedDecl = Result.Nodes.getNodeAs<FunctionDecl>("x");
   if (!MatchedDecl->getIdentifier() || MatchedDecl->getName().startswith("awesome_"))
     return;
   diag(MatchedDecl->getLocation(), "function %%0 is insufficiently awesome")
       << MatchedDecl;
   diag(MatchedDecl->getLocation(), "insert 'awesome'", DiagnosticIDs::Note)
       << FixItHint::CreateInsertion(MatchedDecl->getLocation(), "awesome_");
 }

 } // namespace %(namespace)s
 } // namespace tidy
 } // namespace clang
 """ % {'check_name': check_name_camel,
        'module': module,
        'namespace': namespace})


 # Modifies the module to include the new check.
 def adapt_module(module_path, module, check_name, check_name_camel):
   modulecpp = list(filter(
       lambda p: p.lower() == module.lower() + 'tidymodule.cpp',
       os.listdir(module_path)))[0]
   filename = os.path.join(module_path, modulecpp)
   with io.open(filename, 'r', encoding='utf8') as f:
     lines = f.readlines()

   print('Updating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     header_added = False
     header_found = False
     check_added = False
     check_fq_name = module + '-' + check_name
     check_decl = ('    CheckFactories.registerCheck<' + check_name_camel +
                   '>(\n        "' + check_fq_name + '");\n')

     lines = iter(lines)
     try:
       while True:
         line = next(lines)
         if not header_added:
           match = re.search('#include "(.*)"', line)
           if match:
             header_found = True
             if match.group(1) > check_name_camel:
               header_added = True
               f.write('#include "' + check_name_camel + '.h"\n')
           elif header_found:
             header_added = True
             f.write('#include "' + check_name_camel + '.h"\n')

         if not check_added:
           if line.strip() == '}':
             check_added = True
             f.write(check_decl)
           else:
             match = re.search('registerCheck<(.*)> *\( *(?:"([^"]*)")?', line)
             prev_line = None
             if match:
               current_check_name = match.group(2)
               if current_check_name is None:
                 # If we didn't find the check name on this line, look on the
                 # next one.
                 prev_line = line
                 line = next(lines)
                 match = re.search(' *"([^"]*)"', line)
                 if match:
                   current_check_name = match.group(1)
               if current_check_name > check_fq_name:
                 check_added = True
                 f.write(check_decl)
               if prev_line:
                 f.write(prev_line)
         f.write(line)
     except StopIteration:
       pass


 # Adds a release notes entry.
 def add_release_notes(module_path, module, check_name):
   check_name_dashes = module + '-' + check_name
   filename = os.path.normpath(os.path.join(module_path,
                                            '../../docs/ReleaseNotes.rst'))
   with io.open(filename, 'r', encoding='utf8') as f:
     lines = f.readlines()

   lineMatcher = re.compile('New checks')
   nextSectionMatcher = re.compile('New check aliases')
   checkMatcher = re.compile('- New :doc:`(.*)')

   print('Updating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     note_added = False
     header_found = False
     add_note_here = False

     for line in lines:
       if not note_added:
         match = lineMatcher.match(line)
         match_next = nextSectionMatcher.match(line)
         match_check = checkMatcher.match(line)
         if match_check:
           last_check = match_check.group(1)
           if last_check > check_name_dashes:
             add_note_here = True

         if match_next:
           add_note_here = True

         if match:
           header_found = True
           f.write(line)
           continue

         if line.startswith('^^^^'):
           f.write(line)
           continue

         if header_found and add_note_here:
           if not line.startswith('^^^^'):
             f.write("""- New :doc:`%s
   <clang-tidy/checks/%s>` check.

   FIXME: add release notes.

 """ % (check_name_dashes, check_name_dashes))
             note_added = True

       f.write(line)


 # Adds a test for the check.
 def write_test(module_path, module, check_name, test_extension):
   check_name_dashes = module + '-' + check_name
   filename = os.path.normpath(os.path.join(module_path, '../../test/clang-tidy/checkers',
                                            check_name_dashes + '.' + test_extension))
   print('Creating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     f.write("""// RUN: %%check_clang_tidy %%s %(check_name_dashes)s %%t

 // FIXME: Add something that triggers the check here.
 void f();
 // CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function 'f' is insufficiently awesome [%(check_name_dashes)s]

 // FIXME: Verify the applied fix.
 //   * Make the CHECK patterns specific enough and try to make verified lines
 //     unique to avoid incorrect matches.
 //   * Use {{}} for regular expressions.
 // CHECK-FIXES: {{^}}void awesome_f();{{$}}

 // FIXME: Add something that doesn't trigger the check here.
 void awesome_f2();
 """ % {'check_name_dashes': check_name_dashes})


 def get_actual_filename(dirname, filename):
   if not os.path.isdir(dirname):
     return ""
   name = os.path.join(dirname, filename)
   if (os.path.isfile(name)):
     return name
   caselessname = filename.lower()
   for file in os.listdir(dirname):
     if (file.lower() == caselessname):
       return os.path.join(dirname, file)
   return ""


 # Recreates the list of checks in the docs/clang-tidy/checks directory.
 def update_checks_list(clang_tidy_path):
   docs_dir = os.path.join(clang_tidy_path, '../docs/clang-tidy/checks')
   filename = os.path.normpath(os.path.join(docs_dir, 'list.rst'))
   # Read the content of the current list.rst file
   with io.open(filename, 'r', encoding='utf8') as f:
     lines = f.readlines()
   # Get all existing docs
   doc_files = list(filter(lambda s: s.endswith('.rst') and s != 'list.rst',
                      os.listdir(docs_dir)))
   doc_files.sort()

   def has_auto_fix(check_name):
     dirname, _, check_name = check_name.partition("-")

     checker_code = get_actual_filename(os.path.join(clang_tidy_path, dirname),
                                        get_camel_name(check_name) + '.cpp')

     if not os.path.isfile(checker_code):
       return ""

     with io.open(checker_code, encoding='utf8') as f:
       code = f.read()
       if 'FixItHint' in code or "ReplacementText" in code or "fixit" in code:
         # Some simple heuristics to figure out if a checker has an autofix or not.
         return ' "Yes"'
     return ""

   def process_doc(doc_file):
     check_name = doc_file.replace('.rst', '')

     with io.open(os.path.join(docs_dir, doc_file), 'r', encoding='utf8') as doc:
       content = doc.read()
       match = re.search('.*:orphan:.*', content)

       if match:
         # Orphan page, don't list it.
         return '', ''

       match = re.search('.*:http-equiv=refresh: \d+;URL=(.*).html.*',
                         content)
       # Is it a redirect?
       return check_name, match

   def format_link(doc_file):
     check_name, match = process_doc(doc_file)
     if not match and check_name:
       return '   `%(check)s <%(check)s.html>`_,%(autofix)s\n' % {
         'check': check_name,
         'autofix': has_auto_fix(check_name)
       }
     else:
       return ''

   def format_link_alias(doc_file):
     check_name, match = process_doc(doc_file)
     if match and check_name:
       if match.group(1) == 'https://clang.llvm.org/docs/analyzer/checkers':
         title_redirect = 'Clang Static Analyzer'
       else:
         title_redirect = match.group(1)
       # The checker is just a redirect.
       return '   `%(check)s <%(check)s.html>`_, `%(title)s <%(target)s.html>`_,%(autofix)s\n' % {
         'check': check_name,
         'target': match.group(1),
         'title': title_redirect,
         'autofix': has_auto_fix(match.group(1))
       }
     return ''

   checks = map(format_link, doc_files)
   checks_alias = map(format_link_alias, doc_files)

   print('Updating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     for line in lines:
       f.write(line)
       if line.strip() == ".. csv-table::":
         # We dump the checkers
         f.write('   :header: "Name", "Offers fixes"\n\n')
         f.writelines(checks)
         # and the aliases
         f.write('\n\n')
         f.write('.. csv-table:: Aliases..\n')
         f.write('   :header: "Name", "Redirect", "Offers fixes"\n\n')
         f.writelines(checks_alias)
         break


 # Adds a documentation for the check.
 def write_docs(module_path, module, check_name):
   check_name_dashes = module + '-' + check_name
   filename = os.path.normpath(os.path.join(
       module_path, '../../docs/clang-tidy/checks/', check_name_dashes + '.rst'))
   print('Creating %s...' % filename)
   with io.open(filename, 'w', encoding='utf8') as f:
     f.write(""".. title:: clang-tidy - %(check_name_dashes)s

 %(check_name_dashes)s
 %(underline)s

 FIXME: Describe what patterns does the check detect and why. Give examples.
 """ % {'check_name_dashes': check_name_dashes,
        'underline': '=' * len(check_name_dashes)})


 def get_camel_name(check_name):
   return ''.join(map(lambda elem: elem.capitalize(),
                      check_name.split('-'))) + 'Check'


 def main():
   language_to_extension = {
       'c': 'c',
       'c++': 'cpp',
       'objc': 'm',
       'objc++': 'mm',
   }
   parser = argparse.ArgumentParser()
   parser.add_argument(
       '--update-docs',
       action='store_true',
       help='just update the list of documentation files, then exit')
   parser.add_argument(
       '--language',
       help='language to use for new check (defaults to c++)',
       choices=language_to_extension.keys(),
       default='c++',
       metavar='LANG')
   parser.add_argument(
       'module',
       nargs='?',
       help='module directory under which to place the new tidy check (e.g., misc)')
   parser.add_argument(
       'check',
       nargs='?',
       help='name of new tidy check to add (e.g. foo-do-the-stuff)')
   args = parser.parse_args()

   if args.update_docs:
     update_checks_list(os.path.dirname(sys.argv[0]))
     return

   if not args.module or not args.check:
     print('Module and check must be specified.')
     parser.print_usage()
     return

   module = args.module
   check_name = args.check
   check_name_camel = get_camel_name(check_name)
   if check_name.startswith(module):
     print('Check name "%s" must not start with the module "%s". Exiting.' % (
         check_name, module))
     return
   clang_tidy_path = os.path.dirname(sys.argv[0])
   module_path = os.path.join(clang_tidy_path, module)

   if not adapt_cmake(module_path, check_name_camel):
     return

   # Map module names to namespace names that don't conflict with widely used top-level namespaces.
   if module == 'llvm':
     namespace = module + '_check'
   else:
     namespace = module

   write_header(module_path, module, namespace, check_name, check_name_camel)
   write_implementation(module_path, module, namespace, check_name_camel)
   adapt_module(module_path, module, check_name, check_name_camel)
   add_release_notes(module_path, module, check_name)
   test_extension = language_to_extension.get(args.language)
   write_test(module_path, module, check_name, test_extension)
   write_docs(module_path, module, check_name)
   update_checks_list(clang_tidy_path)
   print('Done. Now it\'s your turn!')


 if __name__ == '__main__':
   main()
	#!/usr/bin/env python
	#
	#===- add_new_check.py - clang-tidy check generator ---------- python ---===#
	#
	# Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	# See https://llvm.org/LICENSE.txt for license information.
	# SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	#
	#===-----------------------------------------------------------------------===#

	from __future__ import print_function
	from __future__ import unicode_literals

	import argparse
	import io
	import os
	import re
	import sys

	# Adapts the module's CMakelist file. Returns 'True' if it could add a new
	# entry and 'False' if the entry already existed.
	def adapt_cmake(module_path, check_name_camel):
	filename = os.path.join(module_path, 'CMakeLists.txt')

	# The documentation files are encoded using UTF-8, however on Windows the
	# default encoding might be different (e.g. CP-1252). To make sure UTF-8 is
	# always used, use `io.open(filename, mode, encoding='utf8')` for reading and
	# writing files here and elsewhere.
	with io.open(filename, 'r', encoding='utf8') as f:
	lines = f.readlines()

	cpp_file = check_name_camel + '.cpp'

	# Figure out whether this check already exists.
	for line in lines:
	if line.strip() == cpp_file:
	return False

	print('Updating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	cpp_found = False
	file_added = False
	for line in lines:
	cpp_line = line.strip().endswith('.cpp')
	if (not file_added) and (cpp_line or cpp_found):
	cpp_found = True
	if (line.strip() > cpp_file) or (not cpp_line):
	f.write(' ' + cpp_file + '\n')
	file_added = True
	f.write(line)

	return True


	# Adds a header for the new check.
	def write_header(module_path, module, namespace, check_name, check_name_camel):
	check_name_dashes = module + '-' + check_name
	filename = os.path.join(module_path, check_name_camel) + '.h'
	print('Creating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	header_guard = ('LLVM_CLANG_TOOLS_EXTRA_CLANG_TIDY_' + module.upper() + '_'
	+ check_name_camel.upper() + '_H')
	f.write('//===--- ')
	f.write(os.path.basename(filename))
	f.write(' - clang-tidy ')
	f.write('-' * max(0, 42 - len(os.path.basename(filename))))
	f.write('- C++ --===//')
	f.write("""
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//

	#ifndef %(header_guard)s
	#define %(header_guard)s

	#include "../ClangTidyCheck.h"

	namespace clang {
	namespace tidy {
	namespace %(namespace)s {

	/// FIXME: Write a short description.
	///
	/// For the user-facing documentation see:
	/// http://clang.llvm.org/extra/clang-tidy/checks/%(check_name_dashes)s.html
	class %(check_name)s : public ClangTidyCheck {
	public:
	%(check_name)s(StringRef Name, ClangTidyContext *Context)
	: ClangTidyCheck(Name, Context) {}
	void registerMatchers(ast_matchers::MatchFinder *Finder) override;
	void check(const ast_matchers::MatchFinder::MatchResult &Result) override;
	};

	} // namespace %(namespace)s
	} // namespace tidy
	} // namespace clang

	#endif // %(header_guard)s
	""" % {'header_guard': header_guard,
	'check_name': check_name_camel,
	'check_name_dashes': check_name_dashes,
	'module': module,
	'namespace': namespace})


	# Adds the implementation of the new check.
	def write_implementation(module_path, module, namespace, check_name_camel):
	filename = os.path.join(module_path, check_name_camel) + '.cpp'
	print('Creating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	f.write('//===--- ')
	f.write(os.path.basename(filename))
	f.write(' - clang-tidy ')
	f.write('-' * max(0, 51 - len(os.path.basename(filename))))
	f.write('-===//')
	f.write("""
	//
	// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
	// See https://llvm.org/LICENSE.txt for license information.
	// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
	//
	//===----------------------------------------------------------------------===//

	#include "%(check_name)s.h"
	#include "clang/AST/ASTContext.h"
	#include "clang/ASTMatchers/ASTMatchFinder.h"

	using namespace clang::ast_matchers;

	namespace clang {
	namespace tidy {
	namespace %(namespace)s {

	void %(check_name)s::registerMatchers(MatchFinder *Finder) {
	// FIXME: Add matchers.
	Finder->addMatcher(functionDecl().bind("x"), this);
	}

	void %(check_name)s::check(const MatchFinder::MatchResult &Result) {
	// FIXME: Add callback implementation.
	const auto *MatchedDecl = Result.Nodes.getNodeAs<FunctionDecl>("x");
	if (!MatchedDecl->getIdentifier() \|\| MatchedDecl->getName().startswith("awesome_"))
	return;
	diag(MatchedDecl->getLocation(), "function %%0 is insufficiently awesome")
	<< MatchedDecl;
	diag(MatchedDecl->getLocation(), "insert 'awesome'", DiagnosticIDs::Note)
	<< FixItHint::CreateInsertion(MatchedDecl->getLocation(), "awesome_");
	}

	} // namespace %(namespace)s
	} // namespace tidy
	} // namespace clang
	""" % {'check_name': check_name_camel,
	'module': module,
	'namespace': namespace})


	# Modifies the module to include the new check.
	def adapt_module(module_path, module, check_name, check_name_camel):
	modulecpp = list(filter(
	lambda p: p.lower() == module.lower() + 'tidymodule.cpp',
	os.listdir(module_path)))[0]
	filename = os.path.join(module_path, modulecpp)
	with io.open(filename, 'r', encoding='utf8') as f:
	lines = f.readlines()

	print('Updating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	header_added = False
	header_found = False
	check_added = False
	check_fq_name = module + '-' + check_name
	check_decl = (' CheckFactories.registerCheck<' + check_name_camel +
	'>(\n "' + check_fq_name + '");\n')

	lines = iter(lines)
	try:
	while True:
	line = next(lines)
	if not header_added:
	match = re.search('#include "(.*)"', line)
	if match:
	header_found = True
	if match.group(1) > check_name_camel:
	header_added = True
	f.write('#include "' + check_name_camel + '.h"\n')
	elif header_found:
	header_added = True
	f.write('#include "' + check_name_camel + '.h"\n')

	if not check_added:
	if line.strip() == '}':
	check_added = True
	f.write(check_decl)
	else:
	match = re.search('registerCheck<(.)> \( (?:"([^"])")?', line)
	prev_line = None
	if match:
	current_check_name = match.group(2)
	if current_check_name is None:
	# If we didn't find the check name on this line, look on the
	# next one.
	prev_line = line
	line = next(lines)
	match = re.search(' "([^"])"', line)
	if match:
	current_check_name = match.group(1)
	if current_check_name > check_fq_name:
	check_added = True
	f.write(check_decl)
	if prev_line:
	f.write(prev_line)
	f.write(line)
	except StopIteration:
	pass


	# Adds a release notes entry.
	def add_release_notes(module_path, module, check_name):
	check_name_dashes = module + '-' + check_name
	filename = os.path.normpath(os.path.join(module_path,
	'../../docs/ReleaseNotes.rst'))
	with io.open(filename, 'r', encoding='utf8') as f:
	lines = f.readlines()

	lineMatcher = re.compile('New checks')
	nextSectionMatcher = re.compile('New check aliases')
	checkMatcher = re.compile('- New :doc:`(.*)')

	print('Updating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	note_added = False
	header_found = False
	add_note_here = False

	for line in lines:
	if not note_added:
	match = lineMatcher.match(line)
	match_next = nextSectionMatcher.match(line)
	match_check = checkMatcher.match(line)
	if match_check:
	last_check = match_check.group(1)
	if last_check > check_name_dashes:
	add_note_here = True

	if match_next:
	add_note_here = True

	if match:
	header_found = True
	f.write(line)
	continue

	if line.startswith('^^^^'):
	f.write(line)
	continue

	if header_found and add_note_here:
	if not line.startswith('^^^^'):
	f.write("""- New :doc:`%s
	<clang-tidy/checks/%s>` check.

	FIXME: add release notes.

	""" % (check_name_dashes, check_name_dashes))
	note_added = True

	f.write(line)


	# Adds a test for the check.
	def write_test(module_path, module, check_name, test_extension):
	check_name_dashes = module + '-' + check_name
	filename = os.path.normpath(os.path.join(module_path, '../../test/clang-tidy/checkers',
	check_name_dashes + '.' + test_extension))
	print('Creating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	f.write("""// RUN: %%check_clang_tidy %%s %(check_name_dashes)s %%t

	// FIXME: Add something that triggers the check here.
	void f();
	// CHECK-MESSAGES: :[[@LINE-1]]:6: warning: function 'f' is insufficiently awesome [%(check_name_dashes)s]

	// FIXME: Verify the applied fix.
	// * Make the CHECK patterns specific enough and try to make verified lines
	// unique to avoid incorrect matches.
	// * Use {{}} for regular expressions.
	// CHECK-FIXES: {{^}}void awesome_f();{{$}}

	// FIXME: Add something that doesn't trigger the check here.
	void awesome_f2();
	""" % {'check_name_dashes': check_name_dashes})


	def get_actual_filename(dirname, filename):
	if not os.path.isdir(dirname):
	return ""
	name = os.path.join(dirname, filename)
	if (os.path.isfile(name)):
	return name
	caselessname = filename.lower()
	for file in os.listdir(dirname):
	if (file.lower() == caselessname):
	return os.path.join(dirname, file)
	return ""


	# Recreates the list of checks in the docs/clang-tidy/checks directory.
	def update_checks_list(clang_tidy_path):
	docs_dir = os.path.join(clang_tidy_path, '../docs/clang-tidy/checks')
	filename = os.path.normpath(os.path.join(docs_dir, 'list.rst'))
	# Read the content of the current list.rst file
	with io.open(filename, 'r', encoding='utf8') as f:
	lines = f.readlines()
	# Get all existing docs
	doc_files = list(filter(lambda s: s.endswith('.rst') and s != 'list.rst',
	os.listdir(docs_dir)))
	doc_files.sort()

	def has_auto_fix(check_name):
	dirname, _, check_name = check_name.partition("-")

	checker_code = get_actual_filename(os.path.join(clang_tidy_path, dirname),
	get_camel_name(check_name) + '.cpp')

	if not os.path.isfile(checker_code):
	return ""

	with io.open(checker_code, encoding='utf8') as f:
	code = f.read()
	if 'FixItHint' in code or "ReplacementText" in code or "fixit" in code:
	# Some simple heuristics to figure out if a checker has an autofix or not.
	return ' "Yes"'
	return ""

	def process_doc(doc_file):
	check_name = doc_file.replace('.rst', '')

	with io.open(os.path.join(docs_dir, doc_file), 'r', encoding='utf8') as doc:
	content = doc.read()
	match = re.search('.:orphan:.', content)

	if match:
	# Orphan page, don't list it.
	return '', ''

	match = re.search('.:http-equiv=refresh: \d+;URL=(.).html.*',
	content)
	# Is it a redirect?
	return check_name, match

	def format_link(doc_file):
	check_name, match = process_doc(doc_file)
	if not match and check_name:
	return ' `%(check)s <%(check)s.html>`_,%(autofix)s\n' % {
	'check': check_name,
	'autofix': has_auto_fix(check_name)
	}
	else:
	return ''

	def format_link_alias(doc_file):
	check_name, match = process_doc(doc_file)
	if match and check_name:
	if match.group(1) == 'https://clang.llvm.org/docs/analyzer/checkers':
	title_redirect = 'Clang Static Analyzer'
	else:
	title_redirect = match.group(1)
	# The checker is just a redirect.
	return ' `%(check)s <%(check)s.html>`_, `%(title)s <%(target)s.html>`_,%(autofix)s\n' % {
	'check': check_name,
	'target': match.group(1),
	'title': title_redirect,
	'autofix': has_auto_fix(match.group(1))
	}
	return ''

	checks = map(format_link, doc_files)
	checks_alias = map(format_link_alias, doc_files)

	print('Updating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	for line in lines:
	f.write(line)
	if line.strip() == ".. csv-table::":
	# We dump the checkers
	f.write(' :header: "Name", "Offers fixes"\n\n')
	f.writelines(checks)
	# and the aliases
	f.write('\n\n')
	f.write('.. csv-table:: Aliases..\n')
	f.write(' :header: "Name", "Redirect", "Offers fixes"\n\n')
	f.writelines(checks_alias)
	break


	# Adds a documentation for the check.
	def write_docs(module_path, module, check_name):
	check_name_dashes = module + '-' + check_name
	filename = os.path.normpath(os.path.join(
	module_path, '../../docs/clang-tidy/checks/', check_name_dashes + '.rst'))
	print('Creating %s...' % filename)
	with io.open(filename, 'w', encoding='utf8') as f:
	f.write(""".. title:: clang-tidy - %(check_name_dashes)s

	%(check_name_dashes)s
	%(underline)s

	FIXME: Describe what patterns does the check detect and why. Give examples.
	""" % {'check_name_dashes': check_name_dashes,
	'underline': '=' * len(check_name_dashes)})


	def get_camel_name(check_name):
	return ''.join(map(lambda elem: elem.capitalize(),
	check_name.split('-'))) + 'Check'


	def main():
	language_to_extension = {
	'c': 'c',
	'c++': 'cpp',
	'objc': 'm',
	'objc++': 'mm',
	}
	parser = argparse.ArgumentParser()
	parser.add_argument(
	'--update-docs',
	action='store_true',
	help='just update the list of documentation files, then exit')
	parser.add_argument(
	'--language',
	help='language to use for new check (defaults to c++)',
	choices=language_to_extension.keys(),
	default='c++',
	metavar='LANG')
	parser.add_argument(
	'module',
	nargs='?',
	help='module directory under which to place the new tidy check (e.g., misc)')
	parser.add_argument(
	'check',
	nargs='?',
	help='name of new tidy check to add (e.g. foo-do-the-stuff)')
	args = parser.parse_args()

	if args.update_docs:
	update_checks_list(os.path.dirname(sys.argv[0]))
	return

	if not args.module or not args.check:
	print('Module and check must be specified.')
	parser.print_usage()
	return

	module = args.module
	check_name = args.check
	check_name_camel = get_camel_name(check_name)
	if check_name.startswith(module):
	print('Check name "%s" must not start with the module "%s". Exiting.' % (
	check_name, module))
	return
	clang_tidy_path = os.path.dirname(sys.argv[0])
	module_path = os.path.join(clang_tidy_path, module)

	if not adapt_cmake(module_path, check_name_camel):
	return

	# Map module names to namespace names that don't conflict with widely used top-level namespaces.
	if module == 'llvm':
	namespace = module + '_check'
	else:
	namespace = module

	write_header(module_path, module, namespace, check_name, check_name_camel)
	write_implementation(module_path, module, namespace, check_name_camel)
	adapt_module(module_path, module, check_name, check_name_camel)
	add_release_notes(module_path, module, check_name)
	test_extension = language_to_extension.get(args.language)
	write_test(module_path, module, check_name, test_extension)
	write_docs(module_path, module, check_name)
	update_checks_list(clang_tidy_path)
	print('Done. Now it\'s your turn!')


	if __name__ == '__main__':
	main()