| # 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 <ping@lfw.org>' |
| __credits__ = \ |
| 'GvR, ESR, Tim Peters, Thomas Wouters, Fred Drake, Skip Montanaro' |
| |
| import string, re |
| from codecs import BOM_UTF8, lookup |
| from lib2to3.pgen2.token import * |
| |
| 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.casefold() != y.casefold() |
| ) |
| |
| Whitespace = r'[ \f\t]*' |
| Comment = r'#[^\r\n]*' |
| Ignore = Whitespace + any(r'\\\r?\n' + Whitespace) + maybe(Comment) |
| Name = 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) |
| 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) |
| |
| tokenprog, pseudoprog, single3prog, double3prog = map( |
| re.compile, (Token, PseudoToken, Single3, 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, |
| **{f"{prefix}'''": single3prog for prefix in _strprefixes}, |
| **{f'{prefix}"""': double3prog for prefix in _strprefixes}, |
| **{prefix: None for prefix in _strprefixes}} |
| |
| triple_quoted = ( |
| {"'''", '"""'} | |
| {f"{prefix}'''" for prefix in _strprefixes} | |
| {f'{prefix}"""' for prefix in _strprefixes} |
| ) |
| single_quoted = ( |
| {"'", '"'} | |
| {f"{prefix}'" for prefix in _strprefixes} | |
| {f'{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) |
| |
| class Untokenizer: |
| |
| def __init__(self): |
| self.tokens = [] |
| self.prev_row = 1 |
| self.prev_col = 0 |
| |
| def add_whitespace(self, start): |
| 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): |
| 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, iterable): |
| 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(br'^[ \t\f]*(?:[#\r\n]|$)', re.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 untokenize(iterable): |
| """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 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 |
| physical line. |
| """ |
| lnum = parenlev = continued = 0 |
| 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 comments or blank lines |
| if line[pos] == '#': |
| 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) |
| else: |
| yield ((NL, COMMENT)[line[pos] == '#'], line[pos:], |
| (lnum, pos), (lnum, len(line)), line) |
| continue |
| |
| if column > indents[-1]: # count indents or dedents |
| indents.append(column) |
| yield (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] |
| |
| 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 string.digits 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 initial.isidentifier(): # 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 == 'def': |
| if (stashed |
| and stashed[0] == NAME |
| and stashed[1] == 'async'): |
| |
| 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 |
| 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) |