text: # -*- coding: utf-8 -*-
  """
  This tokenizer has been copied from the ``tokenize.py`` standard library
  tokenizer. The reason was simple: The standard library tokenizer fails
  if the indentation is not right. To make it possible to do error recovery the
      tokenizer needed to be rewritten.
  
  Basically this is a stripped down version of the standard library module, so
  you can read the documentation there. Additionally we included some speed and
  memory optimizations here.
  """
  from __future__ import absolute_import
  
  import sys
  import string
  import re
  from collections import namedtuple
  import itertools as _itertools
  from codecs import BOM_UTF8
  
  from parso.python.token import PythonTokenTypes
  from parso._compatibility import py_version
  from parso.utils import split_lines
  
  
  STRING = PythonTokenTypes.STRING
  NAME = PythonTokenTypes.NAME
  NUMBER = PythonTokenTypes.NUMBER
  OP = PythonTokenTypes.OP
  NEWLINE = PythonTokenTypes.NEWLINE
  INDENT = PythonTokenTypes.INDENT
  DEDENT = PythonTokenTypes.DEDENT
  ENDMARKER = PythonTokenTypes.ENDMARKER
  ERRORTOKEN = PythonTokenTypes.ERRORTOKEN
  ERROR_DEDENT = PythonTokenTypes.ERROR_DEDENT
  FSTRING_START = PythonTokenTypes.FSTRING_START
  FSTRING_STRING = PythonTokenTypes.FSTRING_STRING
  FSTRING_END = PythonTokenTypes.FSTRING_END
  
  TokenCollection = namedtuple(
      'TokenCollection',
      'pseudo_token single_quoted triple_quoted endpats whitespace '
      'fstring_pattern_map always_break_tokens',
  )
  
  BOM_UTF8_STRING = BOM_UTF8.decode('utf-8')
  
  _token_collection_cache = {}
  
  if py_version >= 30:
      # Python 3 has str.isidentifier() to check if a char is a valid identifier
      is_identifier = str.isidentifier
  else:
      namechars = string.ascii_letters + '_'
      is_identifier = lambda s: s in namechars
  
  
  def group(*choices, **kwargs):
      capture = kwargs.pop('capture', False)  # Python 2, arrghhhhh :(
      assert not kwargs
  
      start = '('
      if not capture:
          start += '?:'
      return start + '|'.join(choices) + ')'
  
  
  def maybe(*choices):
      return group(*choices) + '?'
  
  
  # Return the empty string, plus all of the valid string prefixes.
  def _all_string_prefixes(version_info, include_fstring=False, only_fstring=False):
      def different_case_versions(prefix):
          for s in _itertools.product(*[(c, c.upper()) for c in prefix]):
              yield ''.join(s)
      # The valid string prefixes. Only contain the lower case versions,
      #  and don't contain any permuations (include 'fr', but not
      #  'rf'). The various permutations will be generated.
      valid_string_prefixes = ['b', 'r', 'u']
      if version_info >= (3, 0):
          valid_string_prefixes.append('br')
  
      result = set([''])
      if version_info >= (3, 6) and include_fstring:
          f = ['f', 'fr']
          if only_fstring:
              valid_string_prefixes = f
              result = set()
          else:
              valid_string_prefixes += f
      elif only_fstring:
          return set()
  
      # if we add binary f-strings, add: ['fb', 'fbr']
      for prefix in valid_string_prefixes:
          for t in _itertools.permutations(prefix):
              # create a list with upper and lower versions of each
              #  character
              result.update(different_case_versions(t))
      if version_info <= (2, 7):
          # In Python 2 the order cannot just be random.
          result.update(different_case_versions('ur'))
          result.update(different_case_versions('br'))
      return result
  
  
  def _compile(expr):
      return re.compile(expr, re.UNICODE)
  
  
  def _get_token_collection(version_info):
      try:
          return _token_collection_cache[tuple(version_info)]
      except KeyError:
          _token_collection_cache[tuple(version_info)] = result = \
              _create_token_collection(version_info)
          return result
  
  
  fstring_string_single_line = _compile(r'(?:[^{}\r\n]+|\{\{|\}\})+')
  fstring_string_multi_line = _compile(r'(?:[^{}]+|\{\{|\}\})+')
  
  
  def _create_token_collection(version_info):
      # Note: we use unicode matching for names ("\w") but ascii matching for
      # number literals.
      Whitespace = r'[ \f\t]*'
      whitespace = _compile(Whitespace)
      Comment = r'#[^\r\n]*'
      Name = r'\w+'
  
      if version_info >= (3, 6):
          Hexnumber = r'0[xX](?:_?[0-9a-fA-F])+'
          Binnumber = r'0[bB](?:_?[01])+'
          Octnumber = r'0[oO](?:_?[0-7])+'
          Decnumber = r'(?:0(?:_?0)*|[1-9](?:_?[0-9])*)'
          Intnumber = group(Hexnumber, Binnumber, Octnumber, Decnumber)
          Exponent = r'[eE][-+]?[0-9](?:_?[0-9])*'
          Pointfloat = group(r'[0-9](?:_?[0-9])*\.(?:[0-9](?:_?[0-9])*)?',
                             r'\.[0-9](?:_?[0-9])*') + maybe(Exponent)
          Expfloat = r'[0-9](?:_?[0-9])*' + Exponent
          Floatnumber = group(Pointfloat, Expfloat)
          Imagnumber = group(r'[0-9](?:_?[0-9])*[jJ]', Floatnumber + r'[jJ]')
      else:
          Hexnumber = r'0[xX][0-9a-fA-F]+'
          Binnumber = r'0[bB][01]+'
          if version_info >= (3, 0):
              Octnumber = r'0[oO][0-7]+'
          else:
              Octnumber = '0[oO]?[0-7]+'
          Decnumber = r'(?:0+|[1-9][0-9]*)'
          Intnumber = group(Hexnumber, Binnumber, Octnumber, Decnumber)
          Exponent = r'[eE][-+]?[0-9]+'
          Pointfloat = group(r'[0-9]+\.[0-9]*', r'\.[0-9]+') + maybe(Exponent)
          Expfloat = r'[0-9]+' + Exponent
          Floatnumber = group(Pointfloat, Expfloat)
          Imagnumber = group(r'[0-9]+[jJ]', Floatnumber + r'[jJ]')
      Number = group(Imagnumber, Floatnumber, Intnumber)
  
      # Note that since _all_string_prefixes includes the empty string,
      #  StringPrefix can be the empty string (making it optional).
      possible_prefixes = _all_string_prefixes(version_info)
      StringPrefix = group(*possible_prefixes)
      StringPrefixWithF = group(*_all_string_prefixes(version_info, include_fstring=True))
      fstring_prefixes = _all_string_prefixes(version_info, include_fstring=True, only_fstring=True)
      FStringStart = group(*fstring_prefixes)
  
      # Tail end of ' string.
      Single = r"(?:\\.|[^'\\])*'"
      # Tail end of " string.
      Double = r'(?:\\.|[^"\\])*"'
      # Tail end of ''' string.
      Single3 = r"(?:\\.|'(?!'')|[^'\\])*'''"
      # Tail end of """ string.
      Double3 = r'(?:\\.|"(?!"")|[^"\\])*"""'
      Triple = group(StringPrefixWithF + "'''", StringPrefixWithF + '"""')
  
      # Because of leftmost-then-longest match semantics, be sure to put the
      # longest operators first (e.g., if = came before ==, == would get
      # recognized as two instances of =).
      Operator = group(r"\*\*=?", r">>=?", r"<<=?",
                       r"//=?", r"->",
                       r"[+\-*/%&@`|^!=<>]=?",
                       r"~")
  
      Bracket = '[][(){}]'
  
      special_args = [r'\r\n?', r'\n', r'[:;.,@]']
      if version_info >= (3, 0):
          special_args.insert(0, r'\.\.\.')
      Special = group(*special_args)
  
      Funny = group(Operator, Bracket, Special)
  
      # First (or only) line of ' or " string.
      ContStr = group(StringPrefix + r"'[^\r\n'\\]*(?:\\.[^\r\n'\\]*)*" +
                      group("'", r'\\(?:\r\n?|\n)'),
                      StringPrefix + r'"[^\r\n"\\]*(?:\\.[^\r\n"\\]*)*' +
                      group('"', r'\\(?:\r\n?|\n)'))
      pseudo_extra_pool = [Comment, Triple]
      all_quotes = '"', "'", '"""', "'''"
      if fstring_prefixes:
          pseudo_extra_pool.append(FStringStart + group(*all_quotes))
  
      PseudoExtras = group(r'\\(?:\r\n?|\n)|\Z', *pseudo_extra_pool)
      PseudoToken = group(Whitespace, capture=True) + \
          group(PseudoExtras, Number, Funny, ContStr, Name, capture=True)
  
      # For a given string prefix plus quotes, endpats maps it to a regex
      #  to match the remainder of that string. _prefix can be empty, for
      #  a normal single or triple quoted string (with no prefix).
      endpats = {}
      for _prefix in possible_prefixes:
          endpats[_prefix + "'"] = _compile(Single)
          endpats[_prefix + '"'] = _compile(Double)
          endpats[_prefix + "'''"] = _compile(Single3)
          endpats[_prefix + '"""'] = _compile(Double3)
  
      # A set of all of the single and triple quoted string prefixes,
      #  including the opening quotes.
      single_quoted = set()
      triple_quoted = set()
      fstring_pattern_map = {}
      for t in possible_prefixes:
          for quote in '"', "'":
              single_quoted.add(t + quote)
  
          for quote in '"""', "'''":
              triple_quoted.add(t + quote)
  
      for t in fstring_prefixes:
          for quote in all_quotes:
              fstring_pattern_map[t + quote] = quote
  
      ALWAYS_BREAK_TOKENS = (';', 'import', 'class', 'def', 'try', 'except',
                             'finally', 'while', 'with', 'return')
      pseudo_token_compiled = _compile(PseudoToken)
      return TokenCollection(
          pseudo_token_compiled, single_quoted, triple_quoted, endpats,
          whitespace, fstring_pattern_map, ALWAYS_BREAK_TOKENS
      )
  
  
  class Token(namedtuple('Token', ['type', 'string', 'start_pos', 'prefix'])):
      @property
      def end_pos(self):
          lines = split_lines(self.string)
          if len(lines) > 1:
              return self.start_pos[0] + len(lines) - 1, 0
          else:
              return self.start_pos[0], self.start_pos[1] + len(self.string)
  
  
  class PythonToken(Token):
      def __repr__(self):
          return ('TokenInfo(type=%s, string=%r, start_pos=%r, prefix=%r)' %
                  self._replace(type=self.type.name))
  
  
  class FStringNode(object):
      def __init__(self, quote):
          self.quote = quote
          self.parentheses_count = 0
          self.previous_lines = ''
          self.last_string_start_pos = None
          # In the syntax there can be multiple format_spec's nested:
          # {x:{y:3}}
          self.format_spec_count = 0
  
      def open_parentheses(self, character):
          self.parentheses_count += 1
  
      def close_parentheses(self, character):
          self.parentheses_count -= 1
          if self.parentheses_count == 0:
              # No parentheses means that the format spec is also finished.
              self.format_spec_count = 0
  
      def allow_multiline(self):
          return len(self.quote) == 3
  
      def is_in_expr(self):
          return (self.parentheses_count - self.format_spec_count) > 0
  
  
  def _close_fstring_if_necessary(fstring_stack, string, start_pos, additional_prefix):
      for fstring_stack_index, node in enumerate(fstring_stack):
          if string.startswith(node.quote):
              token = PythonToken(
                  FSTRING_END,
                  node.quote,
                  start_pos,
                  prefix=additional_prefix,
              )
              additional_prefix = ''
              assert not node.previous_lines
              del fstring_stack[fstring_stack_index:]
              return token, '', len(node.quote)
      return None, additional_prefix, 0
  
  
  def _find_fstring_string(endpats, fstring_stack, line, lnum, pos):
      tos = fstring_stack[-1]
      allow_multiline = tos.allow_multiline()
      if allow_multiline:
          match = fstring_string_multi_line.match(line, pos)
      else:
          match = fstring_string_single_line.match(line, pos)
      if match is None:
          return tos.previous_lines, pos
  
      if not tos.previous_lines:
          tos.last_string_start_pos = (lnum, pos)
  
      string = match.group(0)
      for fstring_stack_node in fstring_stack:
          end_match = endpats[fstring_stack_node.quote].match(string)
          if end_match is not None:
              string = end_match.group(0)[:-len(fstring_stack_node.quote)]
  
      new_pos = pos
      new_pos += len(string)
      if allow_multiline and (string.endswith('\n') or string.endswith('\r')):
          tos.previous_lines += string
          string = ''
      else:
          string = tos.previous_lines + string
  
      return string, new_pos
  
  
  def tokenize(code, version_info, start_pos=(1, 0)):
      """Generate tokens from a the source code (string)."""
      lines = split_lines(code, keepends=True)
      return tokenize_lines(lines, version_info, start_pos=start_pos)
  
  
  def _print_tokens(func):
      """
      A small helper function to help debug the tokenize_lines function.
      """
      def wrapper(*args, **kwargs):
          for token in func(*args, **kwargs):
              yield token
  
      return wrapper
  
  
  # @_print_tokens
  def tokenize_lines(lines, version_info, start_pos=(1, 0)):
      """
      A heavily modified Python standard library tokenizer.
  
      Additionally to the default information, yields also the prefix of each
      token. This idea comes from lib2to3. The prefix contains all information
      that is irrelevant for the parser like newlines in parentheses or comments.
      """
      def dedent_if_necessary(start):
          while start < indents[-1]:
              if start > indents[-2]:
                  yield PythonToken(ERROR_DEDENT, '', (lnum, 0), '')
                  break
              yield PythonToken(DEDENT, '', spos, '')
              indents.pop()
  
      pseudo_token, single_quoted, triple_quoted, endpats, whitespace, \
          fstring_pattern_map, always_break_tokens, = \
          _get_token_collection(version_info)
      paren_level = 0  # count parentheses
      indents = [0]
      max = 0
      numchars = '0123456789'
      contstr = ''
      contline = None
      # We start with a newline. This makes indent at the first position
      # possible. It's not valid Python, but still better than an INDENT in the
      # second line (and not in the first). This makes quite a few things in
      # Jedi's fast parser possible.
      new_line = True
      prefix = ''  # Should never be required, but here for safety
      additional_prefix = ''
      first = True
      lnum = start_pos[0] - 1
      fstring_stack = []
      for line in lines:  # loop over lines in stream
          lnum += 1
          pos = 0
          max = len(line)
          if first:
              if line.startswith(BOM_UTF8_STRING):
                  additional_prefix = BOM_UTF8_STRING
                  line = line[1:]
                  max = len(line)
  
              # Fake that the part before was already parsed.
              line = '^' * start_pos[1] + line
              pos = start_pos[1]
              max += start_pos[1]
  
              first = False
  
          if contstr:                                         # continued string
              endmatch = endprog.match(line)
              if endmatch:
                  pos = endmatch.end(0)
                  yield PythonToken(
                      STRING, contstr + line[:pos],
                      contstr_start, prefix)
                  contstr = ''
                  contline = None
              else:
                  contstr = contstr + line
                  contline = contline + line
                  continue
  
          while pos < max:
              if fstring_stack:
                  tos = fstring_stack[-1]
                  if not tos.is_in_expr():
                      string, pos = _find_fstring_string(endpats, fstring_stack, line, lnum, pos)
                      if string:
                          yield PythonToken(
                              FSTRING_STRING, string,
                              tos.last_string_start_pos,
                              # Never has a prefix because it can start anywhere and
                              # include whitespace.
                              prefix=''
                          )
                          tos.previous_lines = ''
                          continue
                      if pos == max:
                          break
  
                  rest = line[pos:]
                  fstring_end_token, additional_prefix, quote_length = _close_fstring_if_necessary(
                      fstring_stack,
                      rest,
                      (lnum, pos),
                      additional_prefix,
                  )
                  pos += quote_length
                  if fstring_end_token is not None:
                      yield fstring_end_token
                      continue
  
              pseudomatch = pseudo_token.match(line, pos)
              if not pseudomatch:                             # scan for tokens
                  match = whitespace.match(line, pos)
                  if pos == 0:
                      for t in dedent_if_necessary(match.end()):
                          yield t
                  pos = match.end()
                  new_line = False
                  yield PythonToken(
                      ERRORTOKEN, line[pos], (lnum, pos),
                      additional_prefix + match.group(0)
                  )
                  additional_prefix = ''
                  pos += 1
                  continue
  
              prefix = additional_prefix + pseudomatch.group(1)
              additional_prefix = ''
              start, pos = pseudomatch.span(2)
              spos = (lnum, start)
              token = pseudomatch.group(2)
              if token == '':
                  assert prefix
                  additional_prefix = prefix
                  # This means that we have a line with whitespace/comments at
                  # the end, which just results in an endmarker.
                  break
              initial = token[0]
  
              if new_line and initial not in '\r\n\\#':
                  new_line = False
                  if paren_level == 0 and not fstring_stack:
                      i = 0
                      indent_start = start
                      while line[i] == '\f':
                          i += 1
                          # TODO don't we need to change spos as well?
                          indent_start -= 1
                      if indent_start > indents[-1]:
                          yield PythonToken(INDENT, '', spos, '')
                          indents.append(indent_start)
                      for t in dedent_if_necessary(indent_start):
                          yield t
  
              if (initial in numchars or                      # ordinary number
                      (initial == '.' and token != '.' and token != '...')):
                  yield PythonToken(NUMBER, token, spos, prefix)
              elif initial in '\r\n':
                  if any(not f.allow_multiline() for f in fstring_stack):
                      # Would use fstring_stack.clear, but that's not available
                      # in Python 2.
                      fstring_stack[:] = []
  
                  if not new_line and paren_level == 0 and not fstring_stack:
                      yield PythonToken(NEWLINE, token, spos, prefix)
                  else:
                      additional_prefix = prefix + token
                  new_line = True
              elif initial == '#':  # Comments
                  assert not token.endswith("\n")
                  additional_prefix = prefix + token
              elif token in triple_quoted:
                  endprog = endpats[token]
                  endmatch = endprog.match(line, pos)
                  if endmatch:                                # all on one line
                      pos = endmatch.end(0)
                      token = line[start:pos]
                      yield PythonToken(STRING, token, spos, prefix)
                  else:
                      contstr_start = (lnum, start)           # multiple lines
                      contstr = line[start:]
                      contline = line
                      break
  
              # Check up to the first 3 chars of the token to see if
              #  they're in the single_quoted set. If so, they start
              #  a string.
              # We're using the first 3, because we're looking for
              #  "rb'" (for example) at the start of the token. If
              #  we switch to longer prefixes, this needs to be
              #  adjusted.
              # Note that initial == token[:1].
              # Also note that single quote checking must come after
              #  triple quote checking (above).
              elif initial in single_quoted or \
                      token[:2] in single_quoted or \
                      token[:3] in single_quoted:
                  if token[-1] in '\r\n':                       # continued string
                      # This means that a single quoted string ends with a
                      # backslash and is continued.
                      contstr_start = lnum, start
                      endprog = (endpats.get(initial) or endpats.get(token[1])
                                 or endpats.get(token[2]))
                      contstr = line[start:]
                      contline = line
                      break
                  else:                                       # ordinary string
                      yield PythonToken(STRING, token, spos, prefix)
              elif token in fstring_pattern_map:  # The start of an fstring.
                  fstring_stack.append(FStringNode(fstring_pattern_map[token]))
                  yield PythonToken(FSTRING_START, token, spos, prefix)
              elif is_identifier(initial):                      # ordinary name
                  if token in always_break_tokens:
                      fstring_stack[:] = []
                      paren_level = 0
                      # We only want to dedent if the token is on a new line.
                      if re.match(r'[ \f\t]*$', line[:start]):
                          while True:
                              indent = indents.pop()
                              if indent > start:
                                  yield PythonToken(DEDENT, '', spos, '')
                              else:
                                  indents.append(indent)
                                  break
                  yield PythonToken(NAME, token, spos, prefix)
              elif initial == '\\' and line[start:] in ('\\\n', '\\\r\n', '\\\r'):  # continued stmt
                  additional_prefix += prefix + line[start:]
                  break
              else:
                  if token in '([{':
                      if fstring_stack:
                          fstring_stack[-1].open_parentheses(token)
                      else:
                          paren_level += 1
                  elif token in ')]}':
                      if fstring_stack:
                          fstring_stack[-1].close_parentheses(token)
                      else:
                          if paren_level:
                              paren_level -= 1
                  elif token == ':' and fstring_stack \
                          and fstring_stack[-1].parentheses_count == 1:
                      fstring_stack[-1].format_spec_count += 1
  
                  yield PythonToken(OP, token, spos, prefix)
  
      if contstr:
          yield PythonToken(ERRORTOKEN, contstr, contstr_start, prefix)
          if contstr.endswith('\n') or contstr.endswith('\r'):
              new_line = True
  
      end_pos = lnum, max
      # As the last position we just take the maximally possible position. We
      # remove -1 for the last new line.
      for indent in indents[1:]:
          yield PythonToken(DEDENT, '', end_pos, '')
      yield PythonToken(ENDMARKER, '', end_pos, additional_prefix)
  
  
  if __name__ == "__main__":
      if len(sys.argv) >= 2:
          path = sys.argv[1]
          with open(path) as f:
              code = f.read()
      else:
          code = sys.stdin.read()
  
      from parso.utils import python_bytes_to_unicode, parse_version_string
  
      if isinstance(code, bytes):
          code = python_bytes_to_unicode(code)
  
      for token in tokenize(code, parse_version_string()):
          print(token)
  