def _GetToplevelReorderSpans()

in build-support/iwyu/fix_includes.py [0:0]

• 39 lines of code
• 21 McCabe index (conditional complexity)

def _GetToplevelReorderSpans(file_lines):
  """Returns a sorted list of all reorder_spans not inside an #ifdef/namespace.

  This routine looks at all the reorder_spans in file_lines, ignores
  reorder spans inside #ifdefs and namespaces -- except for the 'header
  guard' ifdef that encapsulates an entire .h file -- and returns the
  rest in sorted order.

  Arguments:
    file_lines: an array of LineInfo objects with .type and
       .reorder_span filled in.

  Returns:
    A list of [start_line, end_line) reorder_spans.
  """
  in_ifdef = [False] * len(file_lines)   # lines inside an #if
  ifdef_depth = 0
  for line_number in range(len(file_lines)):
    line_info = file_lines[line_number]
    if line_info.deleted:
      continue
    if line_info.type == _IF_RE:  # does not cover the header-guard ifdef
      ifdef_depth += 1
    elif line_info.type == _ENDIF_RE:
      ifdef_depth -= 1
    if ifdef_depth > 0:
      in_ifdef[line_number] = True

  # Figuring out whether a } ends a namespace or some other languague
  # construct is hard, so as soon as we see any 'contentful' line
  # inside a namespace, we assume the entire rest of the file is in
  # the namespace.
  in_namespace = [False] * len(file_lines)
  namespace_depth = 0
  for line_number in range(len(file_lines)):
    line_info = file_lines[line_number]
    if line_info.deleted:
      continue
    if line_info.type == _NAMESPACE_START_RE:
      # The 'max' is because the namespace-re may be a macro.
      namespace_depth += max(line_info.line.count('{'), 1)
    elif line_info.type == _NAMESPACE_END_RE:
      namespace_depth -= max(line_info.line.count('}'), 1)
    if namespace_depth > 0:
      in_namespace[line_number] = True
      if line_info.type is None:
        for i in range(line_number, len(file_lines)):  # rest of file
          in_namespace[i] = True
        break

  reorder_spans = [fl.reorder_span for fl in file_lines if fl.reorder_span]
  reorder_spans = sorted(set(reorder_spans))
  good_reorder_spans = []
  for reorder_span in reorder_spans:
    for line_number in range(*reorder_span):
      if in_ifdef[line_number] or in_namespace[line_number]:
        break
    else:   # for/else
      good_reorder_spans.append(reorder_span)    # never in ifdef or namespace

  return good_reorder_spans