def IsRValueAllowed()

in build-support/cpplint.py [0:0]

• 32 lines of code
• 17 McCabe index (conditional complexity)

def IsRValueAllowed(clean_lines, linenum, typenames):
  """Check if RValue reference is allowed on a particular line.

  Args:
    clean_lines: A CleansedLines instance containing the file.
    linenum: The number of the line to check.
    typenames: set of type names from template-argument-list.
  Returns:
    True if line is within the region where RValue references are allowed.
  """
  # Allow region marked by PUSH/POP macros
  for i in xrange(linenum, 0, -1):
    line = clean_lines.elided[i]
    if Match(r'GOOGLE_ALLOW_RVALUE_REFERENCES_(?:PUSH|POP)', line):
      if not line.endswith('PUSH'):
        return False
      for j in xrange(linenum, clean_lines.NumLines(), 1):
        line = clean_lines.elided[j]
        if Match(r'GOOGLE_ALLOW_RVALUE_REFERENCES_(?:PUSH|POP)', line):
          return line.endswith('POP')

  # Allow operator=
  line = clean_lines.elided[linenum]
  if Search(r'\boperator\s*=\s*\(', line):
    return IsDeletedOrDefault(clean_lines, linenum)

  # Allow constructors
  match = Match(r'\s*(?:[\w<>]+::)*([\w<>]+)\s*::\s*([\w<>]+)\s*\(', line)
  if match and match.group(1) == match.group(2):
    return IsDeletedOrDefault(clean_lines, linenum)
  if Search(r'\b(?:explicit|inline)\s+[\w<>]+\s*\(', line):
    return IsDeletedOrDefault(clean_lines, linenum)

  if Match(r'\s*[\w<>]+\s*\(', line):
    previous_line = 'ReturnType'
    if linenum > 0:
      previous_line = clean_lines.elided[linenum - 1]
    if Match(r'^\s*$', previous_line) or Search(r'[{}:;]\s*$', previous_line):
      return IsDeletedOrDefault(clean_lines, linenum)

  # Reject types not mentioned in template-argument-list
  while line:
    match = Match(r'^.*?(\w+)\s*&&(.*)$', line)
    if not match:
      break
    if match.group(1) not in typenames:
      return False
    line = match.group(2)

  # All RValue types that were in template-argument-list should have
  # been removed by now.  Those were allowed, assuming that they will
  # be forwarded.
  #
  # If there are no remaining RValue types left (i.e. types that were
  # not found in template-argument-list), flag those as not allowed.
  return line.find('&&') < 0