widelands-dev team mailing list archive

[GunChleoc <fios@xxxxxxxxxxxxxxxxxxx>]

GunChleoc has proposed merging lp:~widelands-dev/widelands/clang-tidy into lp:widelands.

Commit message:
Added a utils script to run clang-tidy.

Requested reviews:
  Widelands Developers (widelands-dev)
Related bugs:
  Bug #1731034 in widelands: "Use clang-tidy to clean up the codebase"
  https://bugs.launchpad.net/widelands/+bug/1731034

For more details, see:
https://code.launchpad.net/~widelands-dev/widelands/clang-tidy/+merge/333407

I downloaded a script to run clang-tidy and added some documentation to it on how I run it.
-- 
Your team Widelands Developers is requested to review the proposed merge of lp:~widelands-dev/widelands/clang-tidy into lp:widelands.

=== added file 'utils/run-clang-tidy.py'
--- utils/run-clang-tidy.py	1970-01-01 00:00:00 +0000
+++ utils/run-clang-tidy.py	2017-11-08 20:00:32 +0000
@@ -0,0 +1,342 @@
+#!/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
+#
+#===------------------------------------------------------------------------===#
+#
+# Downloaded from https://github.com/llvm-mirror/clang-tools-extra/blob/master/clang-tidy/tool/run-clang-tidy.py
+# Version 38b98640c3820151aa4aba16c5b7797ec8c8b3e7
+#
+#===------------------------------------------------------------------------===#
+# HOW TO RUN THIS TOOL
+#
+# 1. Install the needed libraries. On Ubuntu, this is:
+#
+#       sudo apt-get install clang clang-tidy python-yaml
+#
+# 2. Run compile.sh to create the build directory. You can abort this pretty quick.
+#
+# 3. Run the following commands:
+#
+#        cd build
+#        cmake -DCMAKE_EXPORT_COMPILE_COMMANDS=ON ..
+#
+#    This will give you a file 'build/compile_commands.json'
+#
+# 4. In 'build/compile_commands.json', do replace-all with an empty string
+#    for the following switvhed that would clutter the result with warnings:
+#
+#        -Wlogical-op
+#        -Wsync-nand
+#        -Wtrampolines
+#        -fext-numeric-literals
+#
+# 5. Run the tool from the 'build' directory with:
+#
+#        python ../utils/run-clang-tidy.py -checks=*,-llvm-*,-cppcoreguidelines-pro-type-vararg,-cppcoreguidelines-pro-type-const-cast,-readability-named-parameter > ../clang-tidy.log
+#
+#    Results will then be in 'clang-tidy.log'
+#
+# 6. You can pick with warnings you want with the checks parameter.
+#
+# 7. Documentation is available at:
+#
+#        https://www.kdab.com/clang-tidy-part-1-modernize-source-code-using-c11c14/
+#
+#        http://clang.llvm.org/extra/clang-tidy/
+#
+#===------------------------------------------------------------------------===#
+#
+
+"""
+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()