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remove sys_version for Python 3...
remove sys_version for Python 3 since we're now committed to using Python3, I decided to go through and clean up the code base to remove paths which depend on sys_version checks for Python3

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"""Patched version of standard library tokenize, to deal with various bugs.
Based on Python 3.2 code.
- Gareth Rees' patch for Python issue #12691 (untokenizing)
- Except we don't encode the output of untokenize
- Python 2 compatible syntax, so that it can be byte-compiled at installation
- Newlines in comments and blank lines should be either NL or NEWLINE, depending
on whether they are in a multi-line statement. Filed as Python issue #17061.
- Export generate_tokens & TokenError
- u and rb literals are allowed under Python 3.3 and above.
Tokenization help for Python programs.
tokenize(readline) is a generator that breaks a stream of bytes into
Python tokens. It decodes the bytes according to PEP-0263 for
determining source file encoding.
It accepts a readline-like method which is called repeatedly to get the
next line of input (or b"" for EOF). It generates 5-tuples with these
the token type (see token.py)
the token (a string)
the starting (row, column) indices of the token (a 2-tuple of ints)
the ending (row, column) indices of the token (a 2-tuple of ints)
the original line (string)
It is designed to match the working of the Python tokenizer exactly, except
that it produces COMMENT tokens for comments and gives type OP for all
operators. Additionally, all token lists start with an ENCODING token
which tells you which encoding was used to decode the bytes stream.
from __future__ import absolute_import
__author__ = 'Ka-Ping Yee <ping@lfw.org>'
__credits__ = ('GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, '
'Skip Montanaro, Raymond Hettinger, Trent Nelson, '
'Michael Foord')
import builtins
import re
import sys
from token import *
from codecs import lookup, BOM_UTF8
import collections
from io import TextIOWrapper
cookie_re = re.compile("coding[:=]\s*([-\w.]+)")
import token
__all__ = token.__all__ + ["COMMENT", "tokenize", "detect_encoding",
"NL", "untokenize", "ENCODING", "TokenInfo"]
del token
__all__ += ["generate_tokens", "TokenError"]
tok_name[COMMENT] = 'COMMENT'
tok_name[NL] = 'NL'
class TokenInfo(collections.namedtuple('TokenInfo', 'type string start end line')):
def __repr__(self):
annotated_type = '%d (%s)' % (self.type, tok_name[self.type])
return ('TokenInfo(type=%s, string=%r, start=%r, end=%r, line=%r)' %
def group(*choices): return '(' + '|'.join(choices) + ')'
def any(*choices): return group(*choices) + '*'
def maybe(*choices): return group(*choices) + '?'
# Note: we use unicode matching for names ("\w") but ascii matching for
# number literals.
Whitespace = r'[ \f\t]*'
Comment = r'#[^\r\n]*'
Ignore = Whitespace + any(r'\\\r?\n' + Whitespace) + maybe(Comment)
Name = r'\w+'
Hexnumber = r'0[xX][0-9a-fA-F]+'
Binnumber = r'0[bB][01]+'
Octnumber = r'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)
if sys.version_info.minor >= 3:
StringPrefix = r'(?:[bB][rR]?|[rR][bB]?|[uU])?'
StringPrefix = r'(?:[bB]?[rR]?)?'
# 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(StringPrefix + "'''", StringPrefix + '"""')
# Single-line ' or " string.
String = group(StringPrefix + r"'[^\n'\\]*(?:\\.[^\n'\\]*)*'",
StringPrefix + r'"[^\n"\\]*(?:\\.[^\n"\\]*)*"')
# 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"->",
Bracket = '[][(){}]'
Special = group(r'\r?\n', r'\.\.\.', r'[:;.,@]')
Funny = group(Operator, Bracket, Special)
PlainToken = group(Number, Funny, String, Name)
Token = Ignore + PlainToken
# First (or only) line of ' or " string.
ContStr = group(StringPrefix + r"'[^\n'\\]*(?:\\.[^\n'\\]*)*" +
group("'", r'\\\r?\n'),
StringPrefix + r'"[^\n"\\]*(?:\\.[^\n"\\]*)*' +
group('"', r'\\\r?\n'))
PseudoExtras = group(r'\\\r?\n', Comment, Triple)
PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name)
def _compile(expr):
return re.compile(expr, re.UNICODE)
tokenprog, pseudoprog, single3prog, double3prog = map(
_compile, (Token, PseudoToken, Single3, Double3))
endprogs = {"'": _compile(Single), '"': _compile(Double),
"'''": single3prog, '"""': double3prog,
"r'''": single3prog, 'r"""': double3prog,
"b'''": single3prog, 'b"""': double3prog,
"R'''": single3prog, 'R"""': double3prog,
"B'''": single3prog, 'B"""': double3prog,
"br'''": single3prog, 'br"""': double3prog,
"bR'''": single3prog, 'bR"""': double3prog,
"Br'''": single3prog, 'Br"""': double3prog,
"BR'''": single3prog, 'BR"""': double3prog,
'r': None, 'R': None, 'b': None, 'B': None}
triple_quoted = {}
for t in ("'''", '"""',
"r'''", 'r"""', "R'''", 'R"""',
"b'''", 'b"""', "B'''", 'B"""',
"br'''", 'br"""', "Br'''", 'Br"""',
"bR'''", 'bR"""', "BR'''", 'BR"""'):
triple_quoted[t] = t
single_quoted = {}
for t in ("'", '"',
"r'", 'r"', "R'", 'R"',
"b'", 'b"', "B'", 'B"',
"br'", 'br"', "Br'", 'Br"',
"bR'", 'bR"', "BR'", 'BR"' ):
single_quoted[t] = t
if sys.version_info.minor >= 3:
# Python 3.3
for _prefix in ['rb', 'rB', 'Rb', 'RB', 'u', 'U']:
_t2 = _prefix+'"""'
endprogs[_t2] = double3prog
triple_quoted[_t2] = _t2
_t1 = _prefix + "'''"
endprogs[_t1] = single3prog
triple_quoted[_t1] = _t1
single_quoted[_prefix+'"'] = _prefix+'"'
single_quoted[_prefix+"'"] = _prefix+"'"
del _prefix, _t2, _t1
endprogs['u'] = None
endprogs['U'] = None
del _compile
tabsize = 8
class TokenError(Exception): pass
class StopTokenizing(Exception): pass
class Untokenizer:
def __init__(self):
self.tokens = []
self.prev_row = 1
self.prev_col = 0
self.encoding = 'utf-8'
def add_whitespace(self, tok_type, start):
row, col = start
assert row >= self.prev_row
col_offset = col - self.prev_col
if col_offset > 0:
self.tokens.append(" " * col_offset)
elif row > self.prev_row and tok_type not in (NEWLINE, NL, ENDMARKER):
# Line was backslash-continued.
self.tokens.append(" ")
def untokenize(self, tokens):
iterable = iter(tokens)
for t in iterable:
if len(t) == 2:
self.compat(t, iterable)
tok_type, token, start, end = t[:4]
if tok_type == ENCODING:
self.encoding = token
self.add_whitespace(tok_type, start)
self.prev_row, self.prev_col = end
if tok_type in (NEWLINE, NL):
self.prev_row += 1
self.prev_col = 0
return "".join(self.tokens)
def compat(self, token, iterable):
# This import is here to avoid problems when the itertools
# module is not built yet and tokenize is imported.
from itertools import chain
startline = False
prevstring = False
indents = []
toks_append = self.tokens.append
for tok in chain([token], iterable):
toknum, tokval = tok[:2]
if toknum == ENCODING:
self.encoding = tokval
if toknum in (NAME, NUMBER):
tokval += ' '
# Insert a space between two consecutive strings
if toknum == STRING:
if prevstring:
tokval = ' ' + tokval
prevstring = True
prevstring = False
if toknum == INDENT:
elif toknum == DEDENT:
elif toknum in (NEWLINE, NL):
startline = True
elif startline and indents:
startline = False
def untokenize(tokens):
Convert ``tokens`` (an iterable) back into Python source code. Return
a bytes object, encoded using the encoding specified by the last
ENCODING token in ``tokens``, or UTF-8 if no ENCODING token is found.
The result is guaranteed to tokenize back to match the input so that
the conversion is lossless and round-trips are assured. The
guarantee applies only to the token type and token string as the
spacing between tokens (column positions) may change.
:func:`untokenize` has two modes. If the input tokens are sequences
of length 2 (``type``, ``string``) then spaces are added as necessary to
preserve the round-trip property.
If the input tokens are sequences of length 4 or more (``type``,
``string``, ``start``, ``end``), as returned by :func:`tokenize`, then
spaces are added so that each token appears in the result at the
position indicated by ``start`` and ``end``, if possible.
return Untokenizer().untokenize(tokens)
def _get_normal_name(orig_enc):
"""Imitates get_normal_name in tokenizer.c."""
# Only care about the first 12 characters.
enc = orig_enc[:12].lower().replace("_", "-")
if enc == "utf-8" or enc.startswith("utf-8-"):
return "utf-8"
if enc in ("latin-1", "iso-8859-1", "iso-latin-1") or \
enc.startswith(("latin-1-", "iso-8859-1-", "iso-latin-1-")):
return "iso-8859-1"
return orig_enc
def detect_encoding(readline):
The detect_encoding() function is used to detect the encoding that should
be used to decode a Python source file. It requires one argment, readline,
in the same way as the tokenize() generator.
It will call readline a maximum of twice, and return the encoding used
(as a string) and a list of any lines (left as bytes) it has read in.
It detects the encoding from the presence of a utf-8 bom or an encoding
cookie as specified in pep-0263. If both a bom and a cookie are present,
but disagree, a SyntaxError will be raised. If the encoding cookie is an
invalid charset, raise a SyntaxError. Note that if a utf-8 bom is found,
'utf-8-sig' is returned.
If no encoding is specified, then the default of 'utf-8' will be returned.
bom_found = False
encoding = None
default = 'utf-8'
def read_or_stop():
return readline()
except StopIteration:
return b''
def find_cookie(line):
# Decode as UTF-8. Either the line is an encoding declaration,
# in which case it should be pure ASCII, or it must be UTF-8
# per default encoding.
line_string = line.decode('utf-8')
except UnicodeDecodeError:
raise SyntaxError("invalid or missing encoding declaration")
matches = cookie_re.findall(line_string)
if not matches:
return None
encoding = _get_normal_name(matches[0])
codec = lookup(encoding)
except LookupError:
# This behaviour mimics the Python interpreter
raise SyntaxError("unknown encoding: " + encoding)
if bom_found:
if encoding != 'utf-8':
# This behaviour mimics the Python interpreter
raise SyntaxError('encoding problem: utf-8')
encoding += '-sig'
return encoding
first = read_or_stop()
if first.startswith(BOM_UTF8):
bom_found = True
first = first[3:]
default = 'utf-8-sig'
if not first:
return default, []
encoding = find_cookie(first)
if encoding:
return encoding, [first]
second = read_or_stop()
if not second:
return default, [first]
encoding = find_cookie(second)
if encoding:
return encoding, [first, second]
return default, [first, second]
def open(filename):
"""Open a file in read only mode using the encoding detected by
buffer = builtins.open(filename, 'rb')
encoding, lines = detect_encoding(buffer.readline)
text = TextIOWrapper(buffer, encoding, line_buffering=True)
text.mode = 'r'
return text
def tokenize(readline):
The tokenize() generator requires one argment, readline, which
must be a callable object which provides the same interface as the
readline() method of built-in file objects. Each call to the function
should return one line of input as bytes. Alternately, readline
can be a callable function terminating with StopIteration:
readline = open(myfile, 'rb').__next__ # Example of alternate readline
The generator produces 5-tuples with these members: the token type; the
token string; a 2-tuple (srow, scol) of ints specifying the row and
column where the token begins in the source; a 2-tuple (erow, ecol) of
ints specifying the row and column where the token ends in the source;
and the line on which the token was found. The line passed is the
logical line; continuation lines are included.
The first token sequence will always be an ENCODING token
which tells you which encoding was used to decode the bytes stream.
# This import is here to avoid problems when the itertools module is not
# built yet and tokenize is imported.
from itertools import chain, repeat
encoding, consumed = detect_encoding(readline)
rl_gen = iter(readline, b"")
empty = repeat(b"")
return _tokenize(chain(consumed, rl_gen, empty).__next__, encoding)
def _tokenize(readline, encoding):
lnum = parenlev = continued = 0
numchars = '0123456789'
contstr, needcont = '', 0
contline = None
indents = [0]
if encoding is not None:
if encoding == "utf-8-sig":
# BOM will already have been stripped.
encoding = "utf-8"
yield TokenInfo(ENCODING, encoding, (0, 0), (0, 0), '')
while True: # loop over lines in stream
line = readline()
except StopIteration:
line = b''
if encoding is not None:
line = line.decode(encoding)
lnum += 1
pos, max = 0, len(line)
if contstr: # continued string
if not line:
raise TokenError("EOF in multi-line string", strstart)
endmatch = endprog.match(line)
if endmatch:
pos = end = endmatch.end(0)
yield TokenInfo(STRING, contstr + line[:end],
strstart, (lnum, end), contline + line)
contstr, needcont = '', 0
contline = None
elif needcont and line[-2:] != '\\\n' and line[-3:] != '\\\r\n':
yield TokenInfo(ERRORTOKEN, contstr + line,
strstart, (lnum, len(line)), contline)
contstr = ''
contline = None
contstr = contstr + line
contline = contline + line
elif parenlev == 0 and not continued: # new statement
if not line: break
column = 0
while pos < max: # measure leading whitespace
if line[pos] == ' ':
column += 1
elif line[pos] == '\t':
column = (column//tabsize + 1)*tabsize
elif line[pos] == '\f':
column = 0
pos += 1
if pos == max:
if line[pos] in '#\r\n': # skip comments or blank lines
if line[pos] == '#':
comment_token = line[pos:].rstrip('\r\n')
nl_pos = pos + len(comment_token)
yield TokenInfo(COMMENT, comment_token,
(lnum, pos), (lnum, pos + len(comment_token)), line)
yield TokenInfo(NEWLINE, line[nl_pos:],
(lnum, nl_pos), (lnum, len(line)), line)
yield TokenInfo(NEWLINE, line[pos:],
(lnum, pos), (lnum, len(line)), line)
if column > indents[-1]: # count indents or dedents
yield TokenInfo(INDENT, line[:pos], (lnum, 0), (lnum, pos), line)
while column < indents[-1]:
if column not in indents:
raise IndentationError(
"unindent does not match any outer indentation level",
("<tokenize>", lnum, pos, line))
indents = indents[:-1]
yield TokenInfo(DEDENT, '', (lnum, pos), (lnum, pos), line)
else: # continued statement
if not line:
raise TokenError("EOF in multi-line statement", (lnum, 0))
continued = 0
while pos < max:
pseudomatch = pseudoprog.match(line, pos)
if pseudomatch: # scan for tokens
start, end = pseudomatch.span(1)
spos, epos, pos = (lnum, start), (lnum, end), end
token, initial = line[start:end], line[start]
if (initial in numchars or # ordinary number
(initial == '.' and token != '.' and token != '...')):
yield TokenInfo(NUMBER, token, spos, epos, line)
elif initial in '\r\n':
yield TokenInfo(NL if parenlev > 0 else NEWLINE,
token, spos, epos, line)
elif initial == '#':
assert not token.endswith("\n")
yield TokenInfo(COMMENT, token, spos, epos, line)
elif token in triple_quoted:
endprog = endprogs[token]
endmatch = endprog.match(line, pos)
if endmatch: # all on one line
pos = endmatch.end(0)
token = line[start:pos]
yield TokenInfo(STRING, token, spos, (lnum, pos), line)
strstart = (lnum, start) # multiple lines
contstr = line[start:]
contline = line
elif initial in single_quoted or \
token[:2] in single_quoted or \
token[:3] in single_quoted:
if token[-1] == '\n': # continued string
strstart = (lnum, start)
endprog = (endprogs[initial] or endprogs[token[1]] or
contstr, needcont = line[start:], 1
contline = line
else: # ordinary string
yield TokenInfo(STRING, token, spos, epos, line)
elif initial.isidentifier(): # ordinary name
yield TokenInfo(NAME, token, spos, epos, line)
elif initial == '\\': # continued stmt
continued = 1
if initial in '([{':
parenlev += 1
elif initial in ')]}':
parenlev -= 1
yield TokenInfo(OP, token, spos, epos, line)
yield TokenInfo(ERRORTOKEN, line[pos],
(lnum, pos), (lnum, pos+1), line)
pos += 1
for indent in indents[1:]: # pop remaining indent levels
yield TokenInfo(DEDENT, '', (lnum, 0), (lnum, 0), '')
yield TokenInfo(ENDMARKER, '', (lnum, 0), (lnum, 0), '')
# An undocumented, backwards compatible, API for all the places in the standard
# library that expect to be able to use tokenize with strings
def generate_tokens(readline):
return _tokenize(readline, None)
if __name__ == "__main__":
# Quick sanity check
s = b'''def parseline(self, line):
"""Parse the line into a command name and a string containing
the arguments. Returns a tuple containing (command, args, line).
'command' and 'args' may be None if the line couldn't be parsed.
line = line.strip()
if not line:
return None, None, line
elif line[0] == '?':
line = 'help ' + line[1:]
elif line[0] == '!':
if hasattr(self, 'do_shell'):
line = 'shell ' + line[1:]
return None, None, line
i, n = 0, len(line)
while i < n and line[i] in self.identchars: i = i+1
cmd, arg = line[:i], line[i:].strip()
return cmd, arg, line
for tok in tokenize(iter(s.splitlines()).__next__):