cq/scripts/slave/step/compdb_gen_step.py

"""
  Build step class for generating compilation database from build directory,
  it is useful for analysis tools that require actual compilation command,
  e.g. clang-tidy and iwyu
"""

from __future__ import absolute_import
import logging
import os

from helpers import commit_message_utils
from helpers import diff_utils
from helpers import git_utils
from slave import base_step

BUILD_SCRIPT_PROJECT = 'chromecast/internal'
BUILD_SCRIPT_REL_PATH = 'build/build_chromecast.py'


class CompdbGenStep(base_step.BaseStep):
  """Build step class for generating compilation database"""

  def __init__(self, build_dir, **kwargs):
    """Creates a CompdbGenStep instance.

    Args:
      build_dir: The relative path that contains the build. (relative to
        chromium/src project path)
      **kwargs: Any additional args to pass to BaseStep.
    """
    base_step.BaseStep.__init__(self, name='compdb_gen', **kwargs)
    self._build_dir = build_dir

  def run(self):
    """ Use gn to generate compilation database

    Returns:
      True iff success.
    """

    # Make sure build directory exists before using it to generate
    # compilation database. (because the next call to exec_subprocess_chain
    # can fail silently if the first command files)
    returncode, _, _ = self.exec_subprocess(
        ['ls', self._build_dir], cwd=self.get_project_path('chromium/src'))

    if returncode != 0:
      logging.info(
          'Build directory does not exist. May need to update the build_dir '
          'argument passed into this step.')
      return False

    compdb_gen_command = ([
        'ninja', '-C', self._build_dir, '-t', 'compdb', 'cxx', 'cc'
    ], {
        'cwd': self.get_project_path('chromium/src')
    })

    write_to_file = (['cp', '/dev/stdin', 'compile_commands.json'], {
        'cwd': self.get_project_path('chromium/src')
    })

    _, _, _ = self.exec_subprocess_chain([compdb_gen_command, write_to_file])

    # Remove rbe specific parameters from compilation database, which
    # present before the path of clang++ compiler. This is not required but
    # can reduce unnecessary warnings output by clang_tidy/iwyu
    # pylint: disable=line-too-long
    patch_rbe_command = [
        'sed', '-i',
        's|"command":.*\.\./\.\./third_party/llvm-build/Release+Asserts/bin/clang++'
        ' |"command": '
        '"../../third_party/llvm-build/Release+Asserts/bin/clang++ |g',
        'compile_commands.json'
    ]

    _, _, _ = self.exec_subprocess(
        patch_rbe_command, cwd=self.get_project_path('chromium/src'))

    # Do the same for clang
    # pylint: disable=line-too-long
    patch_rbe_command = [
        'sed', '-i',
        's|"command":.*\.\./\.\./third_party/llvm-build/Release+Asserts/bin/clang'
        ' |"command": "../../third_party/llvm-build/Release+Asserts/bin/clang '
        '|g', 'compile_commands.json'
    ]

    _, _, _ = self.exec_subprocess(
        patch_rbe_command, cwd=self.get_project_path('chromium/src'))

    return True