Mini Shell
# -*- 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 re
import itertools as _itertools
from codecs import BOM_UTF8
from typing import NamedTuple, Tuple, Iterator, Iterable, List, Dict, \
Pattern, Set
from parso.python.token import PythonTokenTypes
from parso.utils import split_lines, PythonVersionInfo, parse_version_string
# Maximum code point of Unicode 6.0: 0x10ffff (1,114,111)
MAX_UNICODE = '\U0010ffff'
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
class TokenCollection(NamedTuple):
pseudo_token: Pattern
single_quoted: Set[str]
triple_quoted: Set[str]
endpats: Dict[str, Pattern]
whitespace: Pattern
fstring_pattern_map: Dict[str, str]
always_break_tokens: Tuple[str]
BOM_UTF8_STRING = BOM_UTF8.decode('utf-8')
_token_collection_cache: Dict[PythonVersionInfo, TokenCollection] = {}
def group(*choices, capture=False, **kwargs):
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(*, 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', 'br']
result = {''}
if 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))
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
unicode_character_name = r'[A-Za-z0-9\-]+(?: [A-Za-z0-9\-]+)*'
fstring_string_single_line = _compile(
r'(?:\{\{|\}\}|\\N\{' + unicode_character_name
+ r'\}|\\(?:\r\n?|\n)|\\[^\r\nN]|[^{}\r\n\\])+'
)
fstring_string_multi_line = _compile(
r'(?:\{\{|\}\}|\\N\{' + unicode_character_name + r'\}|\\[^N]|[^{}\\])+'
)
fstring_format_spec_single_line = _compile(r'(?:\\(?:\r\n?|\n)|[^{}\r\n])+')
fstring_format_spec_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 = '([A-Za-z_0-9\u0080-' + MAX_UNICODE + ']+)'
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]')
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()
StringPrefix = group(*possible_prefixes)
StringPrefixWithF = group(*_all_string_prefixes(include_fstring=True))
fstring_prefixes = _all_string_prefixes(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'\r\n?', r'\n', r'[;.,@]']
if version_info >= (3, 8):
special_args.insert(0, ":=?")
else:
special_args.insert(0, ":")
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', 'continue',
'break', 'del', 'pass', 'global', 'assert', 'nonlocal')
pseudo_token_compiled = _compile(PseudoToken)
return TokenCollection(
pseudo_token_compiled, single_quoted, triple_quoted, endpats,
whitespace, fstring_pattern_map, set(ALWAYS_BREAK_TOKENS)
)
class Token(NamedTuple):
type: PythonTokenTypes
string: str
start_pos: Tuple[int, int]
prefix: str
@property
def end_pos(self) -> Tuple[int, int]:
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:
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
def is_in_format_spec(self):
return not self.is_in_expr() and self.format_spec_count
def _close_fstring_if_necessary(fstring_stack, string, line_nr, column, additional_prefix):
for fstring_stack_index, node in enumerate(fstring_stack):
lstripped_string = string.lstrip()
len_lstrip = len(string) - len(lstripped_string)
if lstripped_string.startswith(node.quote):
token = PythonToken(
FSTRING_END,
node.quote,
(line_nr, column + len_lstrip),
prefix=additional_prefix+string[:len_lstrip],
)
additional_prefix = ''
assert not node.previous_lines
del fstring_stack[fstring_stack_index:]
return token, '', len(node.quote) + len_lstrip
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 tos.is_in_format_spec():
if allow_multiline:
regex = fstring_format_spec_multi_line
else:
regex = fstring_format_spec_single_line
else:
if allow_multiline:
regex = fstring_string_multi_line
else:
regex = fstring_string_single_line
match = regex.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)
# even if allow_multiline is False, we still need to check for trailing
# newlines, because a single-line f-string can contain line continuations
if 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: str, *, version_info: PythonVersionInfo, start_pos: Tuple[int, int] = (1, 0)
) -> Iterator[PythonToken]:
"""Generate tokens from a the source code (string)."""
lines = split_lines(code, keepends=True)
return tokenize_lines(lines, version_info=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):
print(token) # This print is intentional for debugging!
yield token
return wrapper
# @_print_tokens
def tokenize_lines(
lines: Iterable[str],
*,
version_info: PythonVersionInfo,
indents: List[int] = None,
start_pos: Tuple[int, int] = (1, 0),
is_first_token=True,
) -> Iterator[PythonToken]:
"""
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, start), '')
indents[-1] = start
break
indents.pop()
yield PythonToken(DEDENT, '', spos, '')
pseudo_token, single_quoted, triple_quoted, endpats, whitespace, \
fstring_pattern_map, always_break_tokens, = \
_get_token_collection(version_info)
paren_level = 0 # count parentheses
if indents is None:
indents = [0]
max_ = 0
numchars = '0123456789'
contstr = ''
contline: str
contstr_start: Tuple[int, int]
endprog: Pattern
# 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 = ''
lnum = start_pos[0] - 1
fstring_stack: List[FStringNode] = []
for line in lines: # loop over lines in stream
lnum += 1
pos = 0
max_ = len(line)
if is_first_token:
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]
is_first_token = False
if contstr: # continued string
endmatch = endprog.match(line) # noqa: F821
if endmatch:
pos = endmatch.end(0)
yield PythonToken(
STRING, contstr + line[:pos],
contstr_start, prefix) # noqa: F821
contstr = ''
contline = ''
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
# in an f-string, match until the end of the string
if fstring_stack:
string_line = line
for fstring_stack_node in fstring_stack:
quote = fstring_stack_node.quote
end_match = endpats[quote].match(line, pos)
if end_match is not None:
end_match_string = end_match.group(0)
if len(end_match_string) - len(quote) + pos < len(string_line):
string_line = line[:pos] + end_match_string[:-len(quote)]
pseudomatch = pseudo_token.match(string_line, pos)
else:
pseudomatch = pseudo_token.match(line, pos)
if pseudomatch:
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]
else:
match = whitespace.match(line, pos)
initial = line[match.end()]
start = match.end()
spos = (lnum, start)
if new_line and initial not in '\r\n#' and (initial != '\\' or pseudomatch is None):
new_line = False
if paren_level == 0 and not fstring_stack:
indent_start = start
if indent_start > indents[-1]:
yield PythonToken(INDENT, '', spos, '')
indents.append(indent_start)
yield from dedent_if_necessary(indent_start)
if not pseudomatch: # scan for tokens
match = whitespace.match(line, pos)
if new_line and paren_level == 0 and not fstring_stack:
yield from dedent_if_necessary(match.end())
pos = match.end()
new_line = False
yield PythonToken(
ERRORTOKEN, line[pos], (lnum, pos),
additional_prefix + match.group(0)
)
additional_prefix = ''
pos += 1
continue
if (initial in numchars # ordinary number
or (initial == '.' and token != '.' and token != '...')):
yield PythonToken(NUMBER, token, spos, prefix)
elif pseudomatch.group(3) is not None: # ordinary name
if token in always_break_tokens and (fstring_stack or paren_level):
fstring_stack[:] = []
paren_level = 0
# We only want to dedent if the token is on a new line.
m = re.match(r'[ \f\t]*$', line[:start])
if m is not None:
yield from dedent_if_necessary(m.end())
if token.isidentifier():
yield PythonToken(NAME, token, spos, prefix)
else:
yield from _split_illegal_unicode_name(token, spos, prefix)
elif initial in '\r\n':
if any(not f.allow_multiline() for f in fstring_stack):
fstring_stack.clear()
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") and not token.endswith("\r")
if fstring_stack and fstring_stack[-1].is_in_expr():
# `#` is not allowed in f-string expressions
yield PythonToken(ERRORTOKEN, initial, spos, prefix)
pos = start + 1
else:
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 = spos # 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 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.startswith(':') and fstring_stack \
and fstring_stack[-1].parentheses_count \
- fstring_stack[-1].format_spec_count == 1:
# `:` and `:=` both count
fstring_stack[-1].format_spec_count += 1
token = ':'
pos = start + 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
if fstring_stack:
tos = fstring_stack[-1]
if tos.previous_lines:
yield PythonToken(
FSTRING_STRING, tos.previous_lines,
tos.last_string_start_pos,
# Never has a prefix because it can start anywhere and
# include whitespace.
prefix=''
)
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:]:
indents.pop()
yield PythonToken(DEDENT, '', end_pos, '')
yield PythonToken(ENDMARKER, '', end_pos, additional_prefix)
def _split_illegal_unicode_name(token, start_pos, prefix):
def create_token():
return PythonToken(ERRORTOKEN if is_illegal else NAME, found, pos, prefix)
found = ''
is_illegal = False
pos = start_pos
for i, char in enumerate(token):
if is_illegal:
if char.isidentifier():
yield create_token()
found = char
is_illegal = False
prefix = ''
pos = start_pos[0], start_pos[1] + i
else:
found += char
else:
new_found = found + char
if new_found.isidentifier():
found = new_found
else:
if found:
yield create_token()
prefix = ''
pos = start_pos[0], start_pos[1] + i
found = char
is_illegal = True
if found:
yield create_token()
if __name__ == "__main__":
path = sys.argv[1]
with open(path) as f:
code = f.read()
for token in tokenize(code, version_info=parse_version_string('3.10')):
print(token)
Zerion Mini Shell 1.0