Function _CheckUnwantedDependencies

deps/v8/PRESUBMIT.py:165–282

Runs checkdeps on #include statements added in this change. Breaking - rules is an error, breaking ! rules is a warning.

(input_api, output_api)

def _CheckUnwantedDependencies(input_api, output_api):
  """Runs checkdeps on #include statements added in this
  change. Breaking - rules is an error, breaking ! rules is a
  warning.
  """
  # We need to wait until we have an input_api object and use this
  # roundabout construct to import checkdeps because this file is
  # eval-ed and thus doesn't have __file__.
  original_sys_path = sys.path
  try:
    root = input_api.PresubmitLocalPath()
    if not os.path.exists(os.path.join(root, 'buildtools')):
      root = os.path.dirname(root)
      if not os.path.exists(os.path.join(root, 'buildtools')):
        raise RuntimeError(
            "Failed to find //buildtools directory for checkdeps")
    sys.path = sys.path + [
        input_api.os_path.join(root, 'buildtools', 'checkdeps')
    ]
    import checkdeps
    from cpp_checker import CppChecker
    from rules import Rule
  finally:
    # Restore sys.path to what it was before.
    sys.path = original_sys_path

  def _FilesImpactedByDepsChange(files):
    all_files = [f.AbsoluteLocalPath() for f in files]
    deps_files = [p for p in all_files if IsDepsFile(p)]
    impacted_files = union([_CollectImpactedFiles(path) for path in deps_files])
    impacted_file_objs = [ImpactedFile(path) for path in impacted_files]
    return impacted_file_objs

  def IsDepsFile(p):
    return os.path.isfile(p) and os.path.basename(p) == 'DEPS'

  def union(list_of_lists):
    """Ensure no duplicates"""
    return set(sum(list_of_lists, []))

  def _CollectImpactedFiles(deps_file):
    # TODO(liviurau): Do not walk paths twice. Then we have no duplicates.
    # Higher level DEPS changes may dominate lower level DEPS changes.
    # TODO(liviurau): Check if DEPS changed in the right way.
    # 'include_rules' impact c++ files but 'vars' or 'deps' do not.
    # Maybe we just eval both old and new DEPS content and check
    # if the list are the same.
    result = []
    parent_dir = os.path.dirname(deps_file)
    for relative_f in input_api.change.AllFiles(parent_dir):
      abs_f = os.path.join(parent_dir, relative_f)
      if CppChecker.IsCppFile(abs_f):
        result.append(abs_f)
    return result

  class ImpactedFile(object):
    """Duck type version of AffectedFile needed to check files under directories
    where a DEPS file changed. Extend the interface along the line of