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tokenize.py
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tokenize.py
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# Copyright (c) 2001, 2002, 2003, 2004, 2005, 2006 Python Software Foundation.
# All rights reserved.
# mypy: allow-untyped-defs, allow-untyped-calls
"""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."""
import builtins
import sys
from typing import Callable, Final, Iterable, Iterator, Optional, Pattern, Union
from blib2to3.pgen2.grammar import Grammar
from blib2to3.pgen2.token import (
ASYNC,
AWAIT,
COMMENT,
DEDENT,
ENDMARKER,
ERRORTOKEN,
FSTRING_END,
FSTRING_MIDDLE,
FSTRING_START,
INDENT,
LBRACE,
NAME,
NEWLINE,
NL,
NUMBER,
OP,
RBRACE,
STRING,
tok_name,
)
__author__ = "Ka-Ping Yee <ping@lfw.org>"
__credits__ = "GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, Skip Montanaro"
import re
from codecs import BOM_UTF8, lookup
from . import token
__all__ = [x for x in dir(token) if x[0] != "_"] + [
"tokenize",
"generate_tokens",
"untokenize",
]
del token
def group(*choices: str) -> str:
return "(" + "|".join(choices) + ")"
def any(*choices: str) -> str:
return group(*choices) + "*"
def maybe(*choices: str) -> str:
return group(*choices) + "?"
def _combinations(*l: str) -> set[str]:
return {x + y for x in l for y in l + ("",) if x.casefold() != y.casefold()}
Whitespace = r"[ \f\t]*"
Comment = r"#[^\r\n]*"
Ignore = Whitespace + any(r"\\\r?\n" + Whitespace) + maybe(Comment)
Name = ( # this is invalid but it's fine because Name comes after Number in all groups
r"[^\s#\(\)\[\]\{\}+\-*/!@$%^&=|;:'\",\.<>/?`~\\]+"
)
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"(?:[uUrRbB]|[rR][bB]|[bBuU][rR])?"
_fstringlitprefix = r"(?:rF|FR|Fr|fr|RF|F|rf|f|Rf|fR)"
Triple = group(
_litprefix + "'''",
_litprefix + '"""',
_fstringlitprefix + '"""',
_fstringlitprefix + "'''",
)
# beginning of a single quoted f-string. must not end with `{{` or `\N{`
SingleLbrace = r"(?:\\N{|{{|\\'|[^\n'{])*(?<!\\N)({)(?!{)"
DoubleLbrace = r'(?:\\N{|{{|\\"|[^\n"{])*(?<!\\N)({)(?!{)'
# beginning of a triple quoted f-string. must not end with `{{` or `\N{`
Single3Lbrace = r"(?:\\N{|{{|\\'|'(?!'')|[^'{])*(?<!\\N){(?!{)"
Double3Lbrace = r'(?:\\N{|{{|\\"|"(?!"")|[^"{])*(?<!\\N){(?!{)'
# ! format specifier inside an fstring brace, ensure it's not a `!=` token
Bang = Whitespace + group("!") + r"(?!=)"
bang = re.compile(Bang)
Colon = Whitespace + group(":")
colon = re.compile(Colon)
FstringMiddleAfterColon = group(Whitespace + r".*?") + group("{", "}")
fstring_middle_after_colon = re.compile(FstringMiddleAfterColon)
# 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)
_string_middle_single = r"(?:[^\n'\\]|\\.)*"
_string_middle_double = r'(?:[^\n"\\]|\\.)*'
# FSTRING_MIDDLE and LBRACE, must not end with a `{{` or `\N{`
_fstring_middle_single = SingleLbrace
_fstring_middle_double = DoubleLbrace
# First (or only) line of ' or " string.
ContStr = group(
_litprefix + "'" + _string_middle_single + group("'", r"\\\r?\n"),
_litprefix + '"' + _string_middle_double + group('"', r"\\\r?\n"),
group(_fstringlitprefix + "'") + _fstring_middle_single,
group(_fstringlitprefix + '"') + _fstring_middle_double,
group(_fstringlitprefix + "'") + _string_middle_single + group("'", r"\\\r?\n"),
group(_fstringlitprefix + '"') + _string_middle_double + group('"', r"\\\r?\n"),
)
PseudoExtras = group(r"\\\r?\n", Comment, Triple)
PseudoToken = Whitespace + group(PseudoExtras, Number, Funny, ContStr, Name)
pseudoprog: Final = re.compile(PseudoToken, re.UNICODE)
singleprog = re.compile(Single)
singleprog_plus_lbrace = re.compile(group(SingleLbrace, Single))
doubleprog = re.compile(Double)
doubleprog_plus_lbrace = re.compile(group(DoubleLbrace, Double))
single3prog = re.compile(Single3)
single3prog_plus_lbrace = re.compile(group(Single3Lbrace, Single3))
double3prog = re.compile(Double3)
double3prog_plus_lbrace = re.compile(group(Double3Lbrace, Double3))
_strprefixes = _combinations("r", "R", "b", "B") | {"u", "U", "ur", "uR", "Ur", "UR"}
_fstring_prefixes = _combinations("r", "R", "f", "F") - {"r", "R"}
endprogs: Final = {
"'": singleprog,
'"': doubleprog,
"'''": single3prog,
'"""': double3prog,
**{f"{prefix}'": singleprog for prefix in _strprefixes},
**{f'{prefix}"': doubleprog for prefix in _strprefixes},
**{f"{prefix}'": singleprog_plus_lbrace for prefix in _fstring_prefixes},
**{f'{prefix}"': doubleprog_plus_lbrace for prefix in _fstring_prefixes},
**{f"{prefix}'''": single3prog for prefix in _strprefixes},
**{f'{prefix}"""': double3prog for prefix in _strprefixes},
**{f"{prefix}'''": single3prog_plus_lbrace for prefix in _fstring_prefixes},
**{f'{prefix}"""': double3prog_plus_lbrace for prefix in _fstring_prefixes},
}
triple_quoted: Final = (
{"'''", '"""'}
| {f"{prefix}'''" for prefix in _strprefixes | _fstring_prefixes}
| {f'{prefix}"""' for prefix in _strprefixes | _fstring_prefixes}
)
single_quoted: Final = (
{"'", '"'}
| {f"{prefix}'" for prefix in _strprefixes | _fstring_prefixes}
| {f'{prefix}"' for prefix in _strprefixes | _fstring_prefixes}
)
fstring_prefix: Final = (
{f"{prefix}'" for prefix in _fstring_prefixes}
| {f'{prefix}"' for prefix in _fstring_prefixes}
| {f"{prefix}'''" for prefix in _fstring_prefixes}
| {f'{prefix}"""' for prefix in _fstring_prefixes}
)
tabsize = 8
class TokenError(Exception):
pass
class StopTokenizing(Exception):
pass
Coord = tuple[int, int]
def printtoken(
type: int, token: str, srow_col: Coord, erow_col: Coord, line: str
) -> None: # for testing
(srow, scol) = srow_col
(erow, ecol) = erow_col
print(
"%d,%d-%d,%d:\t%s\t%s" % (srow, scol, erow, ecol, tok_name[type], repr(token))
)
TokenEater = Callable[[int, str, Coord, Coord, str], None]
def tokenize(readline: Callable[[], str], tokeneater: TokenEater = printtoken) -> None:
"""
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: Callable[[], str], tokeneater: TokenEater) -> None:
for token_info in generate_tokens(readline):
tokeneater(*token_info)
GoodTokenInfo = tuple[int, str, Coord, Coord, str]
TokenInfo = Union[tuple[int, str], GoodTokenInfo]
class Untokenizer:
tokens: list[str]
prev_row: int
prev_col: int
def __init__(self) -> None:
self.tokens = []
self.prev_row = 1
self.prev_col = 0
def add_whitespace(self, start: Coord) -> None:
row, col = start
assert row <= self.prev_row
col_offset = col - self.prev_col
if col_offset:
self.tokens.append(" " * col_offset)
def untokenize(self, iterable: Iterable[TokenInfo]) -> str:
for t in iterable:
if len(t) == 2:
self.compat(t, iterable)
break
tok_type, token, start, end, line = t
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
return "".join(self.tokens)
def compat(self, token: tuple[int, str], iterable: Iterable[TokenInfo]) -> None:
startline = False
indents = []
toks_append = self.tokens.append
toknum, tokval = token
if toknum in (NAME, NUMBER):
tokval += " "
if toknum in (NEWLINE, NL):
startline = True
for tok in iterable:
toknum, tokval = tok[:2]
if toknum in (NAME, NUMBER, ASYNC, AWAIT):
tokval += " "
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
toks_append(tokval)
cookie_re = re.compile(r"^[ \t\f]*#.*?coding[:=][ \t]*([-\w.]+)", re.ASCII)
blank_re = re.compile(rb"^[ \t\f]*(?:[#\r\n]|$)", re.ASCII)
def _get_normal_name(orig_enc: str) -> str:
"""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: Callable[[], bytes]) -> tuple[str, list[bytes]]:
"""
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() -> bytes:
try:
return readline()
except StopIteration:
return b""
def find_cookie(line: bytes) -> Optional[str]:
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 untokenize(iterable: Iterable[TokenInfo]) -> str:
"""Transform tokens back into Python source code.
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 text will tokenize the back to the input
t1 = [tok[:2] for tok in generate_tokens(f.readline)]
newcode = untokenize(t1)
readline = iter(newcode.splitlines(1)).next
t2 = [tok[:2] for tokin generate_tokens(readline)]
assert t1 == t2
"""
ut = Untokenizer()
return ut.untokenize(iterable)
def is_fstring_start(token: str) -> bool:
return builtins.any(token.startswith(prefix) for prefix in fstring_prefix)
def _split_fstring_start_and_middle(token: str) -> tuple[str, str]:
for prefix in fstring_prefix:
_, prefix, rest = token.partition(prefix)
if prefix != "":
return prefix, rest
raise ValueError(f"Token {token!r} is not a valid f-string start")
STATE_NOT_FSTRING: Final = 0 # not in an f-string
STATE_MIDDLE: Final = 1 # in the string portion of an f-string (outside braces)
STATE_IN_BRACES: Final = 2 # between braces in an f-string
# in the format specifier (between the colon and the closing brace)
STATE_IN_COLON: Final = 3
class FStringState:
"""Keeps track of state around f-strings.
The tokenizer should call the appropriate method on this class when
it transitions to a different part of an f-string. This is needed
because the tokenization depends on knowing where exactly we are in
the f-string.
For example, consider the following f-string:
f"a{1:b{2}c}d"
The following is the tokenization of this string and the states
tracked by this class:
1,0-1,2: FSTRING_START 'f"' # [STATE_NOT_FSTRING, STATE_MIDDLE]
1,2-1,3: FSTRING_MIDDLE 'a'
1,3-1,4: LBRACE '{' # [STATE_NOT_FSTRING, STATE_IN_BRACES]
1,4-1,5: NUMBER '1'
1,5-1,6: OP ':' # [STATE_NOT_FSTRING, STATE_IN_COLON]
1,6-1,7: FSTRING_MIDDLE 'b'
1,7-1,8: LBRACE '{' # [STATE_NOT_FSTRING, STATE_IN_COLON, STATE_IN_BRACES]
1,8-1,9: NUMBER '2'
1,9-1,10: RBRACE '}' # [STATE_NOT_FSTRING, STATE_IN_COLON]
1,10-1,11: FSTRING_MIDDLE 'c'
1,11-1,12: RBRACE '}' # [STATE_NOT_FSTRING, STATE_MIDDLE]
1,12-1,13: FSTRING_MIDDLE 'd'
1,13-1,14: FSTRING_END '"' # [STATE_NOT_FSTRING]
1,14-1,15: NEWLINE '\n'
2,0-2,0: ENDMARKER ''
Notice that the nested braces in the format specifier are represented
by adding a STATE_IN_BRACES entry to the state stack. The stack is
also used if there are nested f-strings.
"""
def __init__(self) -> None:
self.stack: list[int] = [STATE_NOT_FSTRING]
def is_in_fstring_expression(self) -> bool:
return self.stack[-1] not in (STATE_MIDDLE, STATE_NOT_FSTRING)
def current(self) -> int:
return self.stack[-1]
def enter_fstring(self) -> None:
self.stack.append(STATE_MIDDLE)
def leave_fstring(self) -> None:
state = self.stack.pop()
assert state == STATE_MIDDLE
def consume_lbrace(self) -> None:
current_state = self.stack[-1]
if current_state == STATE_MIDDLE:
self.stack[-1] = STATE_IN_BRACES
elif current_state == STATE_IN_COLON:
self.stack.append(STATE_IN_BRACES)
else:
assert False, current_state
def consume_rbrace(self) -> None:
current_state = self.stack[-1]
assert current_state in (STATE_IN_BRACES, STATE_IN_COLON)
if len(self.stack) > 1 and self.stack[-2] == STATE_IN_COLON:
self.stack.pop()
else:
self.stack[-1] = STATE_MIDDLE
def consume_colon(self) -> None:
assert self.stack[-1] == STATE_IN_BRACES, self.stack
self.stack[-1] = STATE_IN_COLON
def generate_tokens(
readline: Callable[[], str], grammar: Optional[Grammar] = None
) -> Iterator[GoodTokenInfo]:
"""
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
parenlev_stack: list[int] = []
fstring_state = FStringState()
formatspec = ""
numchars: Final[str] = "0123456789"
contstr, needcont = "", 0
contline: Optional[str] = None
indents = [0]
# If we know we're parsing 3.7+, we can unconditionally parse `async` and
# `await` as keywords.
async_keywords = False if grammar is None else grammar.async_keywords
# 'stashed' and 'async_*' are used for async/await parsing
stashed: Optional[GoodTokenInfo] = None
async_def = False
async_def_indent = 0
async_def_nl = False
strstart: tuple[int, int]
endprog_stack: list[Pattern[str]] = []
formatspec_start: tuple[int, int]
while 1: # loop over lines in stream
try:
line = readline()
except StopIteration:
line = ""
lnum += 1
# skip lines that are just indent characters ending with a slash
# to avoid storing that line's indent information.
if not contstr and line.rstrip("\n").strip(" \t\f") == "\\":
continue
pos, max = 0, len(line)
if contstr: # continued string
assert contline is not None
if not line:
raise TokenError("EOF in multi-line string", strstart)
endprog = endprog_stack[-1]
endmatch = endprog.match(line)
if endmatch:
end = endmatch.end(0)
token = contstr + line[:end]
spos = strstart
epos = (lnum, end)
tokenline = contline + line
if fstring_state.current() in (
STATE_NOT_FSTRING,
STATE_IN_BRACES,
) and not is_fstring_start(token):
yield (STRING, token, spos, epos, tokenline)
endprog_stack.pop()
parenlev = parenlev_stack.pop()
else:
if is_fstring_start(token):
fstring_start, token = _split_fstring_start_and_middle(token)
fstring_start_epos = (spos[0], spos[1] + len(fstring_start))
yield (
FSTRING_START,
fstring_start,
spos,
fstring_start_epos,
tokenline,
)
fstring_state.enter_fstring()
# increase spos to the end of the fstring start
spos = fstring_start_epos
if token.endswith("{"):
fstring_middle, lbrace = token[:-1], token[-1]
fstring_middle_epos = lbrace_spos = (lnum, end - 1)
yield (
FSTRING_MIDDLE,
fstring_middle,
spos,
fstring_middle_epos,
line,
)
yield (LBRACE, lbrace, lbrace_spos, epos, line)
fstring_state.consume_lbrace()
else:
if token.endswith(('"""', "'''")):
fstring_middle, fstring_end = token[:-3], token[-3:]
fstring_middle_epos = end_spos = (lnum, end - 3)
else:
fstring_middle, fstring_end = token[:-1], token[-1]
fstring_middle_epos = end_spos = (lnum, end - 1)
yield (
FSTRING_MIDDLE,
fstring_middle,
spos,
fstring_middle_epos,
line,
)
yield (
FSTRING_END,
fstring_end,
end_spos,
epos,
line,
)
fstring_state.leave_fstring()
endprog_stack.pop()
parenlev = parenlev_stack.pop()
pos = end
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
# new statement
elif (
parenlev == 0
and not continued
and not fstring_state.is_in_fstring_expression()
):
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
else:
break
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, nl_pos),
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:
if fstring_state.current() == STATE_MIDDLE:
endprog = endprog_stack[-1]
endmatch = endprog.match(line, pos)
if endmatch: # all on one line
start, end = endmatch.span(0)
token = line[start:end]
if token.endswith(('"""', "'''")):
middle_token, end_token = token[:-3], token[-3:]
middle_epos = end_spos = (lnum, end - 3)
else:
middle_token, end_token = token[:-1], token[-1]
middle_epos = end_spos = (lnum, end - 1)
# TODO: unsure if this can be safely removed
if stashed:
yield stashed
stashed = None
yield (
FSTRING_MIDDLE,
middle_token,
(lnum, pos),
middle_epos,
line,
)
if not token.endswith("{"):
yield (
FSTRING_END,
end_token,
end_spos,
(lnum, end),
line,
)
fstring_state.leave_fstring()
endprog_stack.pop()
parenlev = parenlev_stack.pop()
else:
yield (LBRACE, "{", (lnum, end - 1), (lnum, end), line)
fstring_state.consume_lbrace()
pos = end
continue
else: # multiple lines
strstart = (lnum, end)
contstr = line[end:]
contline = line
break
if fstring_state.current() == STATE_IN_COLON:
match = fstring_middle_after_colon.match(line, pos)
if match is None:
formatspec += line[pos:]
pos = max
continue
start, end = match.span(1)
token = line[start:end]
formatspec += token
brace_start, brace_end = match.span(2)
brace_or_nl = line[brace_start:brace_end]
if brace_or_nl == "\n":
pos = brace_end
yield (FSTRING_MIDDLE, formatspec, formatspec_start, (lnum, end), line)
formatspec = ""
if brace_or_nl == "{":
yield (LBRACE, "{", (lnum, brace_start), (lnum, brace_end), line)
fstring_state.consume_lbrace()
end = brace_end
elif brace_or_nl == "}":
yield (RBRACE, "}", (lnum, brace_start), (lnum, brace_end), line)
fstring_state.consume_rbrace()
end = brace_end
formatspec_start = (lnum, brace_end)
pos = end
continue
if fstring_state.current() == STATE_IN_BRACES and parenlev == 0:
match = bang.match(line, pos)
if match:
start, end = match.span(1)
yield (OP, "!", (lnum, start), (lnum, end), line)
pos = end
continue
match = colon.match(line, pos)
if match:
start, end = match.span(1)
yield (OP, ":", (lnum, start), (lnum, end), line)
fstring_state.consume_colon()
formatspec_start = (lnum, end)
pos = end
continue
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 or fstring_state.is_in_fstring_expression():
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]
endprog_stack.append(endprog)
parenlev_stack.append(parenlev)
parenlev = 0
if is_fstring_start(token):
yield (FSTRING_START, token, spos, epos, line)
fstring_state.enter_fstring()
endmatch = endprog.match(line, pos)
if endmatch: # all on one line
if stashed:
yield stashed
stashed = None
if not is_fstring_start(token):
pos = endmatch.end(0)
token = line[start:pos]
epos = (lnum, pos)
yield (STRING, token, spos, epos, line)
endprog_stack.pop()
parenlev = parenlev_stack.pop()
else:
end = endmatch.end(0)
token = line[pos:end]
spos, epos = (lnum, pos), (lnum, end)
if not token.endswith("{"):
fstring_middle, fstring_end = token[:-3], token[-3:]
fstring_middle_epos = fstring_end_spos = (lnum, end - 3)
yield (
FSTRING_MIDDLE,
fstring_middle,
spos,
fstring_middle_epos,
line,
)
yield (
FSTRING_END,
fstring_end,
fstring_end_spos,
epos,
line,
)
fstring_state.leave_fstring()
endprog_stack.pop()
parenlev = parenlev_stack.pop()
else:
fstring_middle, lbrace = token[:-1], token[-1]
fstring_middle_epos = lbrace_spos = (lnum, end - 1)
yield (
FSTRING_MIDDLE,
fstring_middle,
spos,
fstring_middle_epos,
line,
)
yield (LBRACE, lbrace, lbrace_spos, epos, line)
fstring_state.consume_lbrace()
pos = end
else:
# multiple lines
if is_fstring_start(token):
strstart = (lnum, pos)
contstr = line[pos:]
else:
strstart = (lnum, start)
contstr = line[start:]
contline = line
break
elif (
initial in single_quoted
or token[:2] in single_quoted
or token[:3] in single_quoted
):
maybe_endprog = (
endprogs.get(initial)
or endprogs.get(token[:2])
or endprogs.get(token[:3])
)
assert maybe_endprog is not None, f"endprog not found for {token}"
endprog = maybe_endprog
if token[-1] == "\n": # continued string
endprog_stack.append(endprog)
parenlev_stack.append(parenlev)
parenlev = 0
strstart = (lnum, start)
contstr, needcont = line[start:], 1
contline = line
break
else: # ordinary string
if stashed:
yield stashed
stashed = None
if not is_fstring_start(token):
yield (STRING, token, spos, epos, line)
else:
if pseudomatch[20] is not None:
fstring_start = pseudomatch[20]
offset = pseudomatch.end(20) - pseudomatch.start(1)
elif pseudomatch[22] is not None:
fstring_start = pseudomatch[22]
offset = pseudomatch.end(22) - pseudomatch.start(1)
elif pseudomatch[24] is not None:
fstring_start = pseudomatch[24]
offset = pseudomatch.end(24) - pseudomatch.start(1)
else:
fstring_start = pseudomatch[26]
offset = pseudomatch.end(26) - pseudomatch.start(1)
start_epos = (lnum, start + offset)