Rename tools-webrtc -> tools_webrtc

tools-webrtc/vim/webrtc.ycm_extra_conf.py

-# Copyright (c) 2017 The WebRTC project authors. All Rights Reserved.
-#
-# Use of this source code is governed by a BSD-style license
-# that can be found in the LICENSE file in the root of the source
-# tree. An additional intellectual property rights grant can be found
-# in the file PATENTS.  All contributing project authors may
-# be found in the AUTHORS file in the root of the source tree.
-
-# Autocompletion config for YouCompleteMe in WebRTC. This is just copied from
-# tools/vim in chromium with very minor modifications.
-#
-# USAGE:
-#
-#   1. Install YCM [https://github.com/Valloric/YouCompleteMe]
-#          (Googlers should check out [go/ycm])
-#
-#   2. Create a symbolic link to this file called .ycm_extra_conf.py in the
-#      directory above your WebRTC checkout (i.e. next to your .gclient file).
-#
-#          cd src
-#          ln -rs tools-webrtc/vim/webrtc.ycm_extra_conf.py \
-#          ../.ycm_extra_conf.py
-#
-#   3. (optional) Whitelist the .ycm_extra_conf.py from step #2 by adding the
-#      following to your .vimrc:
-#
-#          let g:ycm_extra_conf_globlist=['<path to .ycm_extra_conf.py>']
-#
-#      You can also add other .ycm_extra_conf.py files you want to use to this
-#      list to prevent excessive prompting each time you visit a directory
-#      covered by a config file.
-#
-#   4. Profit
-#
-#
-# Usage notes:
-#
-#   * You must use ninja & clang to build WebRTC.
-#
-#   * You must have run "gn gen" and built WebRTC recently.
-#
-#
-# Hacking notes:
-#
-#   * The purpose of this script is to construct an accurate enough command line
-#     for YCM to pass to clang so it can build and extract the symbols.
-#
-#   * Right now, we only pull the -I and -D flags. That seems to be sufficient
-#     for everything I've used it for.
-#
-#   * That whole ninja & clang thing? We could support other configs if someone
-#     were willing to write the correct commands and a parser.
-#
-#   * This has only been tested on gPrecise.
-
-
-import os
-import os.path
-import shlex
-import subprocess
-import sys
-
-# Flags from YCM's default config.
-_DEFAULT_FLAGS = [
-  '-DUSE_CLANG_COMPLETER',
-  '-std=c++11',
-  '-x',
-  'c++',
-]
-
-_HEADER_ALTERNATES = ('.cc', '.cpp', '.c', '.mm', '.m')
-
-_EXTENSION_FLAGS = {
-  '.m': ['-x', 'objective-c'],
-  '.mm': ['-x', 'objective-c++'],
-}
-
-def PathExists(*args):
-  return os.path.exists(os.path.join(*args))
-
-
-def FindWebrtcSrcFromFilename(filename):
-  """Searches for the root of the WebRTC checkout.
-
-  Simply checks parent directories until it finds .gclient and src/.
-
-  Args:
-    filename: (String) Path to source file being edited.
-
-  Returns:
-    (String) Path of 'src/', or None if unable to find.
-  """
-  curdir = os.path.normpath(os.path.dirname(filename))
-  while not (os.path.basename(curdir) == 'src'
-             and PathExists(curdir, 'DEPS')
-             and (PathExists(curdir, '..', '.gclient')
-                  or PathExists(curdir, '.git'))):
-    nextdir = os.path.normpath(os.path.join(curdir, '..'))
-    if nextdir == curdir:
-      return None
-    curdir = nextdir
-  return curdir
-
-
-def GetDefaultSourceFile(webrtc_root, filename):
-  """Returns the default source file to use as an alternative to |filename|.
-
-  Compile flags used to build the default source file is assumed to be a
-  close-enough approximation for building |filename|.
-
-  Args:
-    webrtc_root: (String) Absolute path to the root of WebRTC checkout.
-    filename: (String) Absolute path to the source file.
-
-  Returns:
-    (String) Absolute path to substitute source file.
-  """
-  if 'test.' in filename:
-    return os.path.join(webrtc_root, 'base', 'logging_unittest.cc')
-  return os.path.join(webrtc_root, 'base', 'logging.cc')
-
-
-def GetNinjaBuildOutputsForSourceFile(out_dir, filename):
-  """Returns a list of build outputs for filename.
-
-  The list is generated by invoking 'ninja -t query' tool to retrieve a list of
-  inputs and outputs of |filename|. This list is then filtered to only include
-  .o and .obj outputs.
-
-  Args:
-    out_dir: (String) Absolute path to ninja build output directory.
-    filename: (String) Absolute path to source file.
-
-  Returns:
-    (List of Strings) List of target names. Will return [] if |filename| doesn't
-        yield any .o or .obj outputs.
-  """
-  # Ninja needs the path to the source file relative to the output build
-  # directory.
-  rel_filename = os.path.relpath(filename, out_dir)
-
-  p = subprocess.Popen(['ninja', '-C', out_dir, '-t', 'query', rel_filename],
-                       stdout=subprocess.PIPE, stderr=subprocess.STDOUT,
-                       universal_newlines=True)
-  stdout, _ = p.communicate()
-  if p.returncode != 0:
-    return []
-
-  # The output looks like:
-  #   ../../relative/path/to/source.cc:
-  #     outputs:
-  #       obj/reative/path/to/target.source.o
-  #       obj/some/other/target2.source.o
-  #       another/target.txt
-  #
-  outputs_text = stdout.partition('\n  outputs:\n')[2]
-  output_lines = [line.strip() for line in outputs_text.split('\n')]
-  return [target for target in output_lines
-          if target and (target.endswith('.o') or target.endswith('.obj'))]
-
-
-def GetClangCommandLineForNinjaOutput(out_dir, build_target):
-  """Returns the Clang command line for building |build_target|
-
-  Asks ninja for the list of commands used to build |filename| and returns the
-  final Clang invocation.
-
-  Args:
-    out_dir: (String) Absolute path to ninja build output directory.
-    build_target: (String) A build target understood by ninja
-
-  Returns:
-    (String or None) Clang command line or None if a Clang command line couldn't
-        be determined.
-  """
-  p = subprocess.Popen(['ninja', '-v', '-C', out_dir,
-                        '-t', 'commands', build_target],
-                       stdout=subprocess.PIPE, universal_newlines=True)
-  stdout, _ = p.communicate()
-  if p.returncode != 0:
-    return None
-
-  # Ninja will return multiple build steps for all dependencies up to
-  # |build_target|. The build step we want is the last Clang invocation, which
-  # is expected to be the one that outputs |build_target|.
-  for line in reversed(stdout.split('\n')):
-    if 'clang' in line:
-      return line
-  return None
-
-
-def GetClangCommandLineFromNinjaForSource(out_dir, filename):
-  """Returns a Clang command line used to build |filename|.
-
-  The same source file could be built multiple times using different tool
-  chains. In such cases, this command returns the first Clang invocation. We
-  currently don't prefer one toolchain over another. Hopefully the tool chain
-  corresponding to the Clang command line is compatible with the Clang build
-  used by YCM.
-
-  Args:
-    out_dir: (String) Absolute path to WebRTC checkout.
-    filename: (String) Absolute path to source file.
-
-  Returns:
-    (String or None): Command line for Clang invocation using |filename| as a
-        source. Returns None if no such command line could be found.
-  """
-  build_targets = GetNinjaBuildOutputsForSourceFile(out_dir, filename)
-  for build_target in build_targets:
-    command_line = GetClangCommandLineForNinjaOutput(out_dir, build_target)
-    if command_line:
-      return command_line
-  return None
-
-
-def GetClangOptionsFromCommandLine(clang_commandline, out_dir,
-                                   additional_flags):
-  """Extracts relevant command line options from |clang_commandline|
-
-  Args:
-    clang_commandline: (String) Full Clang invocation.
-    out_dir: (String) Absolute path to ninja build directory. Relative paths in
-        the command line are relative to |out_dir|.
-    additional_flags: (List of String) Additional flags to return.
-
-  Returns:
-    (List of Strings) The list of command line flags for this source file. Can
-    be empty.
-  """
-  clang_flags = [] + additional_flags
-
-  # Parse flags that are important for YCM's purposes.
-  clang_tokens = shlex.split(clang_commandline)
-  for flag_index, flag in enumerate(clang_tokens):
-    if flag.startswith('-I'):
-      # Relative paths need to be resolved, because they're relative to the
-      # output dir, not the source.
-      if flag[2] == '/':
-        clang_flags.append(flag)
-      else:
-        abs_path = os.path.normpath(os.path.join(out_dir, flag[2:]))
-        clang_flags.append('-I' + abs_path)
-    elif flag.startswith('-std'):
-      clang_flags.append(flag)
-    elif flag.startswith('-') and flag[1] in 'DWFfmO':
-      if flag == '-Wno-deprecated-register' or flag == '-Wno-header-guard':
-        # These flags causes libclang (3.3) to crash. Remove it until things
-        # are fixed.
-        continue
-      clang_flags.append(flag)
-    elif flag == '-isysroot':
-      # On Mac -isysroot <path> is used to find the system headers.
-      # Copy over both flags.
-      if flag_index + 1 < len(clang_tokens):
-        clang_flags.append(flag)
-        clang_flags.append(clang_tokens[flag_index + 1])
-    elif flag.startswith('--sysroot='):
-      # On Linux we use a sysroot image.
-      sysroot_path = flag.lstrip('--sysroot=')
-      if sysroot_path.startswith('/'):
-        clang_flags.append(flag)
-      else:
-        abs_path = os.path.normpath(os.path.join(out_dir, sysroot_path))
-        clang_flags.append('--sysroot=' + abs_path)
-  return clang_flags
-
-
-def GetClangOptionsFromNinjaForFilename(webrtc_root, filename):
-  """Returns the Clang command line options needed for building |filename|.
-
-  Command line options are based on the command used by ninja for building
-  |filename|. If |filename| is a .h file, uses its companion .cc or .cpp file.
-  If a suitable companion file can't be located or if ninja doesn't know about
-  |filename|, then uses default source files in WebRTC for determining the
-  commandline.
-
-  Args:
-    webrtc_root: (String) Path to src/.
-    filename: (String) Absolute path to source file being edited.
-
-  Returns:
-    (List of Strings) The list of command line flags for this source file. Can
-    be empty.
-  """
-  if not webrtc_root:
-    return []
-
-  # Generally, everyone benefits from including WebRTC's src/, because all of
-  # WebRTC's includes are relative to that.
-  additional_flags = ['-I' + os.path.join(webrtc_root)]
-
-  # Version of Clang used to compile WebRTC can be newer then version of
-  # libclang that YCM uses for completion. So it's possible that YCM's libclang
-  # doesn't know about some used warning options, which causes compilation
-  # warnings (and errors, because of '-Werror');
-  additional_flags.append('-Wno-unknown-warning-option')
-
-  sys.path.append(os.path.join(webrtc_root, 'tools', 'vim'))
-  from ninja_output import GetNinjaOutputDirectory
-  out_dir = GetNinjaOutputDirectory(webrtc_root)
-
-  basename, extension = os.path.splitext(filename)
-  if extension == '.h':
-    candidates = [basename + ext for ext in _HEADER_ALTERNATES]
-  else:
-    candidates = [filename]
-
-  clang_line = None
-  buildable_extension = extension
-  for candidate in candidates:
-    clang_line = GetClangCommandLineFromNinjaForSource(out_dir, candidate)
-    if clang_line:
-      buildable_extension = os.path.splitext(candidate)[1]
-      break
-
-  additional_flags += _EXTENSION_FLAGS.get(buildable_extension, [])
-
-  if not clang_line:
-    # If ninja didn't know about filename or it's companion files, then try a
-    # default build target. It is possible that the file is new, or build.ninja
-    # is stale.
-    clang_line = GetClangCommandLineFromNinjaForSource(
-        out_dir, GetDefaultSourceFile(webrtc_root, filename))
-
-  if not clang_line:
-    return additional_flags
-
-  return GetClangOptionsFromCommandLine(clang_line, out_dir, additional_flags)
-
-
-def FlagsForFile(filename):
-  """This is the main entry point for YCM. Its interface is fixed.
-
-  Args:
-    filename: (String) Path to source file being edited.
-
-  Returns:
-    (Dictionary)
-      'flags': (List of Strings) Command line flags.
-      'do_cache': (Boolean) True if the result should be cached.
-  """
-  abs_filename = os.path.abspath(filename)
-  webrtc_root = FindWebrtcSrcFromFilename(abs_filename)
-  clang_flags = GetClangOptionsFromNinjaForFilename(webrtc_root, abs_filename)
-
-  # If clang_flags could not be determined, then assume that was due to a
-  # transient failure. Preventing YCM from caching the flags allows us to try to
-  # determine the flags again.
-  should_cache_flags_for_file = bool(clang_flags)
-
-  final_flags = _DEFAULT_FLAGS + clang_flags
-
-  return {
-    'flags': final_flags,
-    'do_cache': should_cache_flags_for_file
-  }