mirror of
https://github.com/python/cpython.git
synced 2024-11-27 03:45:08 +08:00
7d2c39752f
As argparse now detects by default when the code was run as a module.
This leads to using the actual executable name instead of simply "python"
to display in the usage message ("usage: python -m ...").
585 lines
21 KiB
Python
585 lines
21 KiB
Python
"""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
|
|
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. Additionally, all token lists start with an ENCODING token
|
|
which tells you which encoding was used to decode the bytes stream.
|
|
"""
|
|
|
|
__author__ = 'Ka-Ping Yee <ping@lfw.org>'
|
|
__credits__ = ('GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, '
|
|
'Skip Montanaro, Raymond Hettinger, Trent Nelson, '
|
|
'Michael Foord')
|
|
from builtins import open as _builtin_open
|
|
from codecs import lookup, BOM_UTF8
|
|
import collections
|
|
import functools
|
|
from io import TextIOWrapper
|
|
import itertools as _itertools
|
|
import re
|
|
import sys
|
|
from token import *
|
|
from token import EXACT_TOKEN_TYPES
|
|
import _tokenize
|
|
|
|
cookie_re = re.compile(r'^[ \t\f]*#.*?coding[:=][ \t]*([-\w.]+)', re.ASCII)
|
|
blank_re = re.compile(br'^[ \t\f]*(?:[#\r\n]|$)', re.ASCII)
|
|
|
|
import token
|
|
__all__ = token.__all__ + ["tokenize", "generate_tokens", "detect_encoding",
|
|
"untokenize", "TokenInfo", "open", "TokenError"]
|
|
del token
|
|
|
|
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)' %
|
|
self._replace(type=annotated_type))
|
|
|
|
@property
|
|
def exact_type(self):
|
|
if self.type == OP and self.string in EXACT_TOKEN_TYPES:
|
|
return EXACT_TOKEN_TYPES[self.string]
|
|
else:
|
|
return self.type
|
|
|
|
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(?:_?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)
|
|
|
|
# Return the empty string, plus all of the valid string prefixes.
|
|
def _all_string_prefixes():
|
|
# The valid string prefixes. Only contain the lower case versions,
|
|
# and don't contain any permutations (include 'fr', but not
|
|
# 'rf'). The various permutations will be generated.
|
|
_valid_string_prefixes = ['b', 'r', 'u', 'f', 'br', 'fr']
|
|
# if we add binary f-strings, add: ['fb', 'fbr']
|
|
result = {''}
|
|
for prefix in _valid_string_prefixes:
|
|
for t in _itertools.permutations(prefix):
|
|
# create a list with upper and lower versions of each
|
|
# character
|
|
for u in _itertools.product(*[(c, c.upper()) for c in t]):
|
|
result.add(''.join(u))
|
|
return result
|
|
|
|
@functools.lru_cache
|
|
def _compile(expr):
|
|
return re.compile(expr, re.UNICODE)
|
|
|
|
# Note that since _all_string_prefixes includes the empty string,
|
|
# StringPrefix can be the empty string (making it optional).
|
|
StringPrefix = group(*_all_string_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(StringPrefix + "'''", StringPrefix + '"""')
|
|
# Single-line ' or " string.
|
|
String = group(StringPrefix + r"'[^\n'\\]*(?:\\.[^\n'\\]*)*'",
|
|
StringPrefix + r'"[^\n"\\]*(?:\\.[^\n"\\]*)*"')
|
|
|
|
# Sorting in reverse order puts the long operators before their prefixes.
|
|
# Otherwise if = came before ==, == would get recognized as two instances
|
|
# of =.
|
|
Special = group(*map(re.escape, sorted(EXACT_TOKEN_TYPES, reverse=True)))
|
|
Funny = group(r'\r?\n', 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|\Z', Comment, Triple)
|
|
PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name)
|
|
|
|
# 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 _all_string_prefixes():
|
|
endpats[_prefix + "'"] = Single
|
|
endpats[_prefix + '"'] = Double
|
|
endpats[_prefix + "'''"] = Single3
|
|
endpats[_prefix + '"""'] = Double3
|
|
del _prefix
|
|
|
|
# A set of all of the single and triple quoted string prefixes,
|
|
# including the opening quotes.
|
|
single_quoted = set()
|
|
triple_quoted = set()
|
|
for t in _all_string_prefixes():
|
|
for u in (t + '"', t + "'"):
|
|
single_quoted.add(u)
|
|
for u in (t + '"""', t + "'''"):
|
|
triple_quoted.add(u)
|
|
del t, u
|
|
|
|
tabsize = 8
|
|
|
|
class TokenError(Exception): pass
|
|
|
|
|
|
class Untokenizer:
|
|
|
|
def __init__(self):
|
|
self.tokens = []
|
|
self.prev_row = 1
|
|
self.prev_col = 0
|
|
self.prev_type = None
|
|
self.encoding = None
|
|
|
|
def add_whitespace(self, start):
|
|
row, col = start
|
|
if row < self.prev_row or row == self.prev_row and col < self.prev_col:
|
|
raise ValueError("start ({},{}) precedes previous end ({},{})"
|
|
.format(row, col, self.prev_row, self.prev_col))
|
|
row_offset = row - self.prev_row
|
|
if row_offset:
|
|
self.tokens.append("\\\n" * row_offset)
|
|
self.prev_col = 0
|
|
col_offset = col - self.prev_col
|
|
if col_offset:
|
|
self.tokens.append(" " * col_offset)
|
|
|
|
def escape_brackets(self, token):
|
|
characters = []
|
|
consume_until_next_bracket = False
|
|
for character in token:
|
|
if character == "}":
|
|
if consume_until_next_bracket:
|
|
consume_until_next_bracket = False
|
|
else:
|
|
characters.append(character)
|
|
if character == "{":
|
|
n_backslashes = sum(
|
|
1 for char in _itertools.takewhile(
|
|
"\\".__eq__,
|
|
characters[-2::-1]
|
|
)
|
|
)
|
|
if n_backslashes % 2 == 0 or characters[-1] != "N":
|
|
characters.append(character)
|
|
else:
|
|
consume_until_next_bracket = True
|
|
characters.append(character)
|
|
return "".join(characters)
|
|
|
|
def untokenize(self, iterable):
|
|
it = iter(iterable)
|
|
indents = []
|
|
startline = False
|
|
for t in it:
|
|
if len(t) == 2:
|
|
self.compat(t, it)
|
|
break
|
|
tok_type, token, start, end, line = t
|
|
if tok_type == ENCODING:
|
|
self.encoding = token
|
|
continue
|
|
if tok_type == ENDMARKER:
|
|
break
|
|
if tok_type == INDENT:
|
|
indents.append(token)
|
|
continue
|
|
elif tok_type == DEDENT:
|
|
indents.pop()
|
|
self.prev_row, self.prev_col = end
|
|
continue
|
|
elif tok_type in (NEWLINE, NL):
|
|
startline = True
|
|
elif startline and indents:
|
|
indent = indents[-1]
|
|
if start[1] >= len(indent):
|
|
self.tokens.append(indent)
|
|
self.prev_col = len(indent)
|
|
startline = False
|
|
elif tok_type == FSTRING_MIDDLE:
|
|
if '{' in token or '}' in token:
|
|
token = self.escape_brackets(token)
|
|
last_line = token.splitlines()[-1]
|
|
end_line, end_col = end
|
|
extra_chars = last_line.count("{{") + last_line.count("}}")
|
|
end = (end_line, end_col + extra_chars)
|
|
elif tok_type in (STRING, FSTRING_START) and self.prev_type in (STRING, FSTRING_END):
|
|
self.tokens.append(" ")
|
|
|
|
self.add_whitespace(start)
|
|
self.tokens.append(token)
|
|
self.prev_row, self.prev_col = end
|
|
if tok_type in (NEWLINE, NL):
|
|
self.prev_row += 1
|
|
self.prev_col = 0
|
|
self.prev_type = tok_type
|
|
return "".join(self.tokens)
|
|
|
|
def compat(self, token, iterable):
|
|
indents = []
|
|
toks_append = self.tokens.append
|
|
startline = token[0] in (NEWLINE, NL)
|
|
prevstring = False
|
|
in_fstring = 0
|
|
|
|
for tok in _itertools.chain([token], iterable):
|
|
toknum, tokval = tok[:2]
|
|
if toknum == ENCODING:
|
|
self.encoding = tokval
|
|
continue
|
|
|
|
if toknum in (NAME, NUMBER):
|
|
tokval += ' '
|
|
|
|
# Insert a space between two consecutive strings
|
|
if toknum == STRING:
|
|
if prevstring:
|
|
tokval = ' ' + tokval
|
|
prevstring = True
|
|
else:
|
|
prevstring = False
|
|
|
|
if toknum == FSTRING_START:
|
|
in_fstring += 1
|
|
elif toknum == FSTRING_END:
|
|
in_fstring -= 1
|
|
if toknum == INDENT:
|
|
indents.append(tokval)
|
|
continue
|
|
elif toknum == DEDENT:
|
|
indents.pop()
|
|
continue
|
|
elif toknum in (NEWLINE, NL):
|
|
startline = True
|
|
elif startline and indents:
|
|
toks_append(indents[-1])
|
|
startline = False
|
|
elif toknum == FSTRING_MIDDLE:
|
|
tokval = self.escape_brackets(tokval)
|
|
|
|
# Insert a space between two consecutive brackets if we are in an f-string
|
|
if tokval in {"{", "}"} and self.tokens and self.tokens[-1] == tokval and in_fstring:
|
|
tokval = ' ' + tokval
|
|
|
|
# Insert a space between two consecutive f-strings
|
|
if toknum in (STRING, FSTRING_START) and self.prev_type in (STRING, FSTRING_END):
|
|
self.tokens.append(" ")
|
|
|
|
toks_append(tokval)
|
|
self.prev_type = toknum
|
|
|
|
|
|
def untokenize(iterable):
|
|
"""Transform tokens back into Python source code.
|
|
It returns a bytes object, encoded using the ENCODING
|
|
token, which is the first token sequence output by tokenize.
|
|
|
|
Each element returned by the iterable must be a token sequence
|
|
with at least two elements, a token number and token value. If
|
|
only two tokens are passed, the resulting output is poor.
|
|
|
|
Round-trip invariant for full input:
|
|
Untokenized source will match input source exactly
|
|
|
|
Round-trip invariant for limited input:
|
|
# Output bytes will tokenize back to the input
|
|
t1 = [tok[:2] for tok in tokenize(f.readline)]
|
|
newcode = untokenize(t1)
|
|
readline = BytesIO(newcode).readline
|
|
t2 = [tok[:2] for tok in tokenize(readline)]
|
|
assert t1 == t2
|
|
"""
|
|
ut = Untokenizer()
|
|
out = ut.untokenize(iterable)
|
|
if ut.encoding is not None:
|
|
out = out.encode(ut.encoding)
|
|
return out
|
|
|
|
|
|
def _get_normal_name(orig_enc):
|
|
"""Imitates get_normal_name in Parser/tokenizer/helpers.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.
|
|
"""
|
|
try:
|
|
filename = readline.__self__.name
|
|
except AttributeError:
|
|
filename = None
|
|
bom_found = False
|
|
encoding = None
|
|
default = 'utf-8'
|
|
def read_or_stop():
|
|
try:
|
|
return readline()
|
|
except StopIteration:
|
|
return b''
|
|
|
|
def find_cookie(line):
|
|
try:
|
|
# 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:
|
|
msg = "invalid or missing encoding declaration"
|
|
if filename is not None:
|
|
msg = '{} for {!r}'.format(msg, filename)
|
|
raise SyntaxError(msg)
|
|
|
|
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
|
|
if filename is None:
|
|
msg = "unknown encoding: " + encoding
|
|
else:
|
|
msg = "unknown encoding for {!r}: {}".format(filename,
|
|
encoding)
|
|
raise SyntaxError(msg)
|
|
|
|
if bom_found:
|
|
if encoding != 'utf-8':
|
|
# This behaviour mimics the Python interpreter
|
|
if filename is None:
|
|
msg = 'encoding problem: utf-8'
|
|
else:
|
|
msg = 'encoding problem for {!r}: utf-8'.format(filename)
|
|
raise SyntaxError(msg)
|
|
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 open(filename):
|
|
"""Open a file in read only mode using the encoding detected by
|
|
detect_encoding().
|
|
"""
|
|
buffer = _builtin_open(filename, 'rb')
|
|
try:
|
|
encoding, lines = detect_encoding(buffer.readline)
|
|
buffer.seek(0)
|
|
text = TextIOWrapper(buffer, encoding, line_buffering=True)
|
|
text.mode = 'r'
|
|
return text
|
|
except:
|
|
buffer.close()
|
|
raise
|
|
|
|
def tokenize(readline):
|
|
"""
|
|
The tokenize() 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 bytes. Alternatively, 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
|
|
physical line.
|
|
|
|
The first token sequence will always be an ENCODING token
|
|
which tells you which encoding was used to decode the bytes stream.
|
|
"""
|
|
encoding, consumed = detect_encoding(readline)
|
|
rl_gen = _itertools.chain(consumed, iter(readline, b""))
|
|
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), '')
|
|
yield from _generate_tokens_from_c_tokenizer(rl_gen.__next__, encoding, extra_tokens=True)
|
|
|
|
def generate_tokens(readline):
|
|
"""Tokenize a source reading Python code as unicode strings.
|
|
|
|
This has the same API as tokenize(), except that it expects the *readline*
|
|
callable to return str objects instead of bytes.
|
|
"""
|
|
return _generate_tokens_from_c_tokenizer(readline, extra_tokens=True)
|
|
|
|
def main():
|
|
import argparse
|
|
|
|
# Helper error handling routines
|
|
def perror(message):
|
|
sys.stderr.write(message)
|
|
sys.stderr.write('\n')
|
|
|
|
def error(message, filename=None, location=None):
|
|
if location:
|
|
args = (filename,) + location + (message,)
|
|
perror("%s:%d:%d: error: %s" % args)
|
|
elif filename:
|
|
perror("%s: error: %s" % (filename, message))
|
|
else:
|
|
perror("error: %s" % message)
|
|
sys.exit(1)
|
|
|
|
# Parse the arguments and options
|
|
parser = argparse.ArgumentParser()
|
|
parser.add_argument(dest='filename', nargs='?',
|
|
metavar='filename.py',
|
|
help='the file to tokenize; defaults to stdin')
|
|
parser.add_argument('-e', '--exact', dest='exact', action='store_true',
|
|
help='display token names using the exact type')
|
|
args = parser.parse_args()
|
|
|
|
try:
|
|
# Tokenize the input
|
|
if args.filename:
|
|
filename = args.filename
|
|
with _builtin_open(filename, 'rb') as f:
|
|
tokens = list(tokenize(f.readline))
|
|
else:
|
|
filename = "<stdin>"
|
|
tokens = _generate_tokens_from_c_tokenizer(
|
|
sys.stdin.readline, extra_tokens=True)
|
|
|
|
|
|
# Output the tokenization
|
|
for token in tokens:
|
|
token_type = token.type
|
|
if args.exact:
|
|
token_type = token.exact_type
|
|
token_range = "%d,%d-%d,%d:" % (token.start + token.end)
|
|
print("%-20s%-15s%-15r" %
|
|
(token_range, tok_name[token_type], token.string))
|
|
except IndentationError as err:
|
|
line, column = err.args[1][1:3]
|
|
error(err.args[0], filename, (line, column))
|
|
except TokenError as err:
|
|
line, column = err.args[1]
|
|
error(err.args[0], filename, (line, column))
|
|
except SyntaxError as err:
|
|
error(err, filename)
|
|
except OSError as err:
|
|
error(err)
|
|
except KeyboardInterrupt:
|
|
print("interrupted\n")
|
|
except Exception as err:
|
|
perror("unexpected error: %s" % err)
|
|
raise
|
|
|
|
def _transform_msg(msg):
|
|
"""Transform error messages from the C tokenizer into the Python tokenize
|
|
|
|
The C tokenizer is more picky than the Python one, so we need to massage
|
|
the error messages a bit for backwards compatibility.
|
|
"""
|
|
if "unterminated triple-quoted string literal" in msg:
|
|
return "EOF in multi-line string"
|
|
return msg
|
|
|
|
def _generate_tokens_from_c_tokenizer(source, encoding=None, extra_tokens=False):
|
|
"""Tokenize a source reading Python code as unicode strings using the internal C tokenizer"""
|
|
if encoding is None:
|
|
it = _tokenize.TokenizerIter(source, extra_tokens=extra_tokens)
|
|
else:
|
|
it = _tokenize.TokenizerIter(source, encoding=encoding, extra_tokens=extra_tokens)
|
|
try:
|
|
for info in it:
|
|
yield TokenInfo._make(info)
|
|
except SyntaxError as e:
|
|
if type(e) != SyntaxError:
|
|
raise e from None
|
|
msg = _transform_msg(e.msg)
|
|
raise TokenError(msg, (e.lineno, e.offset)) from None
|
|
|
|
|
|
if __name__ == "__main__":
|
|
main()
|