# Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006 Python Software Foundation.

# All rights reserved.

"""Tokenization help for Python programs.

generate_tokens(readline) is a generator that breaks a stream of

text into Python tokens. It accepts a readline-like method which is called

repeatedly to get the next line of input (or "" for EOF). It generates

5-tuples with these members:

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

Older entry points

tokenize_loop(readline, tokeneater)

tokenize(readline, tokeneater=printtoken)

are the same, except instead of generating tokens, tokeneater is a callback

function to which the 5 fields described above are passed as 5 arguments,

each time a new token is found."""

__author__ = 'Ka-Ping Yee <[email protected]>'

__credits__ = \

'GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, Skip Montanaro'

import re

from codecs import BOM_UTF8, lookup

from blib2to3.pgen2.token import *

import sys

from . import token

__all__ = [x for x in dir(token) if x[0] != '_'] + ["tokenize",

"generate_tokens", "untokenize"]

del token

try:

bytes

except NameError:

# Support bytes type in Python <= 2.5, so 2to3 turns itself into

# valid Python 3 code.

bytes = str

def group(*choices): return '(' + '|'.join(choices) + ')'

def any(*choices): return group(*choices) + '*'

def maybe(*choices): return group(*choices) + '?'

def _combinations(*l):

return set(

x + y for x in l for y in l + ("",) if x.lower() != y.lower()

)

Whitespace = r'[ \f\t]*'

Comment = r'#[^\r\n]*'

Ignore = Whitespace + any(r'\\\r?\n' + Whitespace) + maybe(Comment)

Name = r'\w+' # this is invalid but it's fine because Name comes after Number in all groups

DollarName = r'\$\w+'

Binnumber = r'0[bB]_?[01]+(?:_[01]+)*'

Hexnumber = r'0[xX]_?[\da-fA-F]+(?:_[\da-fA-F]+)*[lL]?'

Octnumber = r'0[oO]?_?[0-7]+(?:_[0-7]+)*[lL]?'

Decnumber = group(r'[1-9]\d*(?:_\d+)*[lL]?', '0[lL]?')

Intnumber = group(Binnumber, Hexnumber, Octnumber, Decnumber)

Exponent = r'[eE][-+]?\d+(?:_\d+)*'

Pointfloat = group(r'\d+(?:_\d+)*\.(?:\d+(?:_\d+)*)?', r'\.\d+(?:_\d+)*') + maybe(Exponent)

Expfloat = r'\d+(?:_\d+)*' + Exponent

Floatnumber = group(Pointfloat, Expfloat)

Imagnumber = group(r'\d+(?:_\d+)*[jJ]', Floatnumber + r'[jJ]')

Number = group(Imagnumber, Floatnumber, Intnumber)

# Tail end of ' string.

Single = r"[^'\\]*(?:\\.[^'\\]*)*'"

# Tail end of " string.

Double = r'[^"\\]*(?:\\.[^"\\]*)*"'

# Tail end of ''' string.

Single3 = r"[^'\\]*(?:(?:\\.|'(?!''))[^'\\]*)*'''"

# Tail end of """ string.

Double3 = r'[^"\\]*(?:(?:\\.|"(?!""))[^"\\]*)*"""'

_litprefix = r"(?:[uUrRbBfF]|[rR][fFbB]|[fFbBuU][rR])?"

Triple = group(_litprefix + "'''", _litprefix + '"""')

# Single-line ' or " string.

String = group(_litprefix + r"'[^\n'\\]*(?:\\.[^\n'\\]*)*'",

_litprefix + 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"//=?", r"->",

r"[+\-*/%&@|^=<>]=?",

r"~")

Bracket = '[][(){}]'

Special = group(r'\r?\n', r'[:;.,`@]')

Funny = group(Operator, Bracket, Special)

PlainToken = group(Number, Funny, String, Name, DollarName)

Token = Ignore + PlainToken

# First (or only) line of ' or " string.

ContStr = group(_litprefix + r"'[^\n'\\]*(?:\\.[^\n'\\]*)*" +

group("'", r'\\\r?\n'),

_litprefix + r'"[^\n"\\]*(?:\\.[^\n"\\]*)*' +

group('"', r'\\\r?\n'))

PseudoExtras = group(r'\\\r?\n', Comment, Triple)

PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name, DollarName)

tokenprog = re.compile(Token, re.UNICODE)

pseudoprog = re.compile(PseudoToken, re.UNICODE)

single3prog = re.compile(Single3)

double3prog = re.compile(Double3)

_strprefixes = (

_combinations('r', 'R', 'f', 'F') |

_combinations('r', 'R', 'b', 'B') |

{'u', 'U', 'ur', 'uR', 'Ur', 'UR'}

)

endprogs = {"'": re.compile(Single), '"': re.compile(Double),

"'''": single3prog, '"""': double3prog,

}

endprogs.update({prefix+"'''": single3prog for prefix in _strprefixes})

endprogs.update({prefix+'"""': double3prog for prefix in _strprefixes})

endprogs.update({prefix: None for prefix in _strprefixes})

triple_quoted = (

{"'''", '"""'} |

{prefix+"'''" for prefix in _strprefixes} |

{prefix+'"""' for prefix in _strprefixes}

)

single_quoted = (

{"'", '"'} |

{prefix+"'" for prefix in _strprefixes} |

{prefix+'"' for prefix in _strprefixes}

)

tabsize = 8

class TokenError(Exception): pass

class StopTokenizing(Exception): pass

def printtoken(type, token, xxx_todo_changeme, xxx_todo_changeme1, line): # for testing

(srow, scol) = xxx_todo_changeme

(erow, ecol) = xxx_todo_changeme1

print("%d,%d-%d,%d:\t%s\t%s" % \

(srow, scol, erow, ecol, tok_name[type], repr(token)))

def tokenize(readline, tokeneater=printtoken):

"""

The tokenize() function accepts two parameters: one representing the

input stream, and one providing an output mechanism for tokenize().

The first parameter, readline, 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 a string.

The second parameter, tokeneater, must also be a callable object. It is

called once for each token, with five arguments, corresponding to the

tuples generated by generate_tokens().

"""

try:

tokenize_loop(readline, tokeneater)

except StopTokenizing:

pass

# backwards compatible interface

def tokenize_loop(readline, tokeneater):

for token_info in generate_tokens(readline):

tokeneater(*token_info)

if sys.version_info > (3,):

isidentifier = str.isidentifier

else:

IDENTIFIER_RE = re.compile(r"^[^\d\W]\w*$", re.UNICODE)

def isidentifier(s):

return bool(IDENTIFIER_RE.match(s))

ASCII = re.ASCII if sys.version_info > (3,) else 0

cookie_re = re.compile(r'^[ \t\f]*#.*?coding[:=][ \t]*([-\w.]+)', ASCII)

blank_re = re.compile(br'^[ \t\f]*(?:[#\r\n]|$)', ASCII)

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 argument, 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():

try:

return readline()

except StopIteration:

return bytes()

def find_cookie(line):

try:

line_string = line.decode('ascii')

except UnicodeDecodeError:

return None

match = cookie_re.match(line_string)

if not match:

return None

encoding = _get_normal_name(match.group(1))

try:

codec = lookup(encoding)

except LookupError:

# This behaviour mimics the Python interpreter

raise SyntaxError("unknown encoding: " + encoding)

if bom_found:

if codec.name != '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]

if not blank_re.match(first):

return default, [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 generate_tokens(readline):

"""

The generate_tokens() generator requires one argument, 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 a string. Alternately, readline

can be a callable function terminating with StopIteration:

readline = open(myfile).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.

"""

lnum = parenlev = continued = 0

numchars = '0123456789'

contstr, needcont = '', 0

contline = None

indents = [0]

# 'stashed' and 'async_*' are used for async/await parsing

stashed = None

async_def = False

async_def_indent = 0

async_def_nl = False

while 1: # loop over lines in stream

try:

line = readline()

except StopIteration:

line = ''

lnum = 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 (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 (ERRORTOKEN, contstr + line,

strstart, (lnum, len(line)), contline)

contstr = ''

contline = None

continue

else:

contstr = contstr + line

contline = contline + line

continue

elif parenlev == 0 and not continued: # new statement

if not line: break

column = 0

while pos < max: # measure leading whitespace

if line[pos] == ' ': column = column + 1

elif line[pos] == '\t': column = (column//tabsize + 1)*tabsize

elif line[pos] == '\f': column = 0

else: break

pos = pos + 1

if pos == max: break

if stashed:

yield stashed

stashed = None

if line[pos] in '\r\n': # skip blank lines

yield (NL, line[pos:], (lnum, pos), (lnum, len(line)), line)

continue

if line[pos] == '#': # skip comments

comment_token = line[pos:].rstrip('\r\n')

nl_pos = pos + len(comment_token)

yield (COMMENT, comment_token,

(lnum, pos), (lnum, pos + len(comment_token)), line)

yield (NL, line[nl_pos:],

(lnum, nl_pos), (lnum, len(line)), line)

continue

if column > indents[-1]: # count indents

indents.append(column)

yield (INDENT, line[:pos], (lnum, 0), (lnum, pos), line)

while column < indents[-1]: # count dedents

if column not in indents:

raise IndentationError(

"unindent does not match any outer indentation level",

("<tokenize>", lnum, pos, line))

indents = indents[:-1]

if async_def and async_def_indent >= indents[-1]:

async_def = False

async_def_nl = False

async_def_indent = 0

yield (DEDENT, '', (lnum, pos), (lnum, pos), line)

if async_def and async_def_nl and async_def_indent >= indents[-1]:

async_def = False

async_def_nl = False

async_def_indent = 0

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 \

(initial == '.' and token != '.'): # ordinary number

yield (NUMBER, token, spos, epos, line)

elif initial in '\r\n':

newline = NEWLINE

if parenlev > 0:

newline = NL

elif async_def:

async_def_nl = True

if stashed:

yield stashed

stashed = None

yield (newline, token, spos, epos, line)

elif initial == '#':

assert not token.endswith("\n")

if stashed:

yield stashed

stashed = None

yield (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]

if stashed:

yield stashed

stashed = None

yield (STRING, token, spos, (lnum, pos), line)

else:

strstart = (lnum, start) # multiple lines

contstr = line[start:]

contline = line

break

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

endprogs[token[2]])

contstr, needcont = line[start:], 1

contline = line

break

else: # ordinary string

if stashed:

yield stashed

stashed = None

yield (STRING, token, spos, epos, line)

elif isidentifier(initial): # ordinary name

if token in ('async', 'await'):

if async_def:

yield (ASYNC if token == 'async' else AWAIT,

token, spos, epos, line)

continue

tok = (NAME, token, spos, epos, line)

if token == 'async' and not stashed:

stashed = tok

continue

if token in ('def', 'for'):

if (stashed

and stashed[0] == NAME

and stashed[1] == 'async'):

if token == 'def':

async_def = True

async_def_indent = indents[-1]

yield (ASYNC, stashed[1],

stashed[2], stashed[3],

stashed[4])

stashed = None

if stashed:

yield stashed

stashed = None

yield tok

elif initial == '\\': # continued stmt

# This yield is new; needed for better idempotency:

if stashed:

yield stashed

stashed = None

yield (NL, token, spos, (lnum, pos), line)

continued = 1

elif initial == '$':

if stashed:

yield stashed

stashed = None

yield (DOLLARNAME, token, spos, epos, line)

else:

if initial in '([{': parenlev = parenlev + 1

elif initial in ')]}': parenlev = parenlev - 1

if stashed:

yield stashed

stashed = None

yield (OP, token, spos, epos, line)

else:

yield (ERRORTOKEN, line[pos],

(lnum, pos), (lnum, pos+1), line)

pos = pos + 1

if stashed:

yield stashed

stashed = None

for indent in indents[1:]: # pop remaining indent levels

yield (DEDENT, '', (lnum, 0), (lnum, 0), '')

yield (ENDMARKER, '', (lnum, 0), (lnum, 0), '')

if __name__ == '__main__': # testing

import sys

if len(sys.argv) > 1: tokenize(open(sys.argv[1]).readline)

else: tokenize(sys.stdin.readline)