You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
425 lines
15 KiB
425 lines
15 KiB
2 years ago
|
import re
|
||
|
|
import sys
|
||
|
|
|
||
|
|
from webencodings import ascii_lower
|
||
|
|
|
||
|
|
from .ast import (
|
||
|
|
AtKeywordToken, Comment, CurlyBracketsBlock, DimensionToken, FunctionBlock,
|
||
|
|
HashToken, IdentToken, LiteralToken, NumberToken, ParenthesesBlock,
|
||
|
|
ParseError, PercentageToken, SquareBracketsBlock, StringToken,
|
||
|
|
UnicodeRangeToken, URLToken, WhitespaceToken)
|
||
|
|
from .serializer import serialize_string_value, serialize_url
|
||
|
|
|
||
|
|
_NUMBER_RE = re.compile(r'[-+]?([0-9]*\.)?[0-9]+([eE][+-]?[0-9]+)?')
|
||
|
|
_HEX_ESCAPE_RE = re.compile(r'([0-9A-Fa-f]{1,6})[ \n\t]?')
|
||
|
|
|
||
|
|
|
||
|
|
def parse_component_value_list(css, skip_comments=False):
|
||
|
|
"""Parse a list of component values.
|
||
|
|
|
||
|
|
:type css: :obj:`str`
|
||
|
|
:param css: A CSS string.
|
||
|
|
:type skip_comments: :obj:`bool`
|
||
|
|
:param skip_comments:
|
||
|
|
Ignore CSS comments.
|
||
|
|
The return values (and recursively its blocks and functions)
|
||
|
|
will not contain any :class:`~tinycss2.ast.Comment` object.
|
||
|
|
:returns: A list of :term:`component values`.
|
||
|
|
|
||
|
|
"""
|
||
|
|
css = (css.replace('\0', '\uFFFD')
|
||
|
|
# This turns out to be faster than a regexp:
|
||
|
|
.replace('\r\n', '\n').replace('\r', '\n').replace('\f', '\n'))
|
||
|
|
length = len(css)
|
||
|
|
token_start_pos = pos = 0 # Character index in the css source.
|
||
|
|
line = 1 # First line is line 1.
|
||
|
|
last_newline = -1
|
||
|
|
root = tokens = []
|
||
|
|
end_char = None # Pop the stack when encountering this character.
|
||
|
|
stack = [] # Stack of nested blocks: (tokens, end_char) tuples.
|
||
|
|
|
||
|
|
while pos < length:
|
||
|
|
newline = css.rfind('\n', token_start_pos, pos)
|
||
|
|
if newline != -1:
|
||
|
|
line += 1 + css.count('\n', token_start_pos, newline)
|
||
|
|
last_newline = newline
|
||
|
|
# First character in a line is in column 1.
|
||
|
|
column = pos - last_newline
|
||
|
|
token_start_pos = pos
|
||
|
|
c = css[pos]
|
||
|
|
|
||
|
|
if c in ' \n\t':
|
||
|
|
pos += 1
|
||
|
|
while css.startswith((' ', '\n', '\t'), pos):
|
||
|
|
pos += 1
|
||
|
|
value = css[token_start_pos:pos]
|
||
|
|
tokens.append(WhitespaceToken(line, column, value))
|
||
|
|
continue
|
||
|
|
elif (c in 'Uu' and pos + 2 < length and css[pos + 1] == '+' and
|
||
|
|
css[pos + 2] in '0123456789abcdefABCDEF?'):
|
||
|
|
start, end, pos = _consume_unicode_range(css, pos + 2)
|
||
|
|
tokens.append(UnicodeRangeToken(line, column, start, end))
|
||
|
|
continue
|
||
|
|
elif css.startswith('-->', pos): # Check before identifiers
|
||
|
|
tokens.append(LiteralToken(line, column, '-->'))
|
||
|
|
pos += 3
|
||
|
|
continue
|
||
|
|
elif _is_ident_start(css, pos):
|
||
|
|
value, pos = _consume_ident(css, pos)
|
||
|
|
if not css.startswith('(', pos): # Not a function
|
||
|
|
tokens.append(IdentToken(line, column, value))
|
||
|
|
continue
|
||
|
|
pos += 1 # Skip the '('
|
||
|
|
if ascii_lower(value) == 'url':
|
||
|
|
url_pos = pos
|
||
|
|
while css.startswith((' ', '\n', '\t'), url_pos):
|
||
|
|
url_pos += 1
|
||
|
|
if url_pos >= length or css[url_pos] not in ('"', "'"):
|
||
|
|
value, pos, error = _consume_url(css, pos)
|
||
|
|
if value is not None:
|
||
|
|
repr = 'url({})'.format(serialize_url(value))
|
||
|
|
if error is not None:
|
||
|
|
error_key = error[0]
|
||
|
|
if error_key == 'eof-in-string':
|
||
|
|
repr = repr[:-2]
|
||
|
|
else:
|
||
|
|
assert error_key == 'eof-in-url'
|
||
|
|
repr = repr[:-1]
|
||
|
|
tokens.append(URLToken(line, column, value, repr))
|
||
|
|
if error is not None:
|
||
|
|
tokens.append(ParseError(line, column, *error))
|
||
|
|
continue
|
||
|
|
arguments = []
|
||
|
|
tokens.append(FunctionBlock(line, column, value, arguments))
|
||
|
|
stack.append((tokens, end_char))
|
||
|
|
end_char = ')'
|
||
|
|
tokens = arguments
|
||
|
|
continue
|
||
|
|
|
||
|
|
match = _NUMBER_RE.match(css, pos)
|
||
|
|
if match:
|
||
|
|
pos = match.end()
|
||
|
|
repr_ = css[token_start_pos:pos]
|
||
|
|
value = float(repr_)
|
||
|
|
int_value = int(repr_) if not any(match.groups()) else None
|
||
|
|
if pos < length and _is_ident_start(css, pos):
|
||
|
|
unit, pos = _consume_ident(css, pos)
|
||
|
|
tokens.append(DimensionToken(
|
||
|
|
line, column, value, int_value, repr_, unit))
|
||
|
|
elif css.startswith('%', pos):
|
||
|
|
pos += 1
|
||
|
|
tokens.append(PercentageToken(
|
||
|
|
line, column, value, int_value, repr_))
|
||
|
|
else:
|
||
|
|
tokens.append(NumberToken(
|
||
|
|
line, column, value, int_value, repr_))
|
||
|
|
elif c == '@':
|
||
|
|
pos += 1
|
||
|
|
if pos < length and _is_ident_start(css, pos):
|
||
|
|
value, pos = _consume_ident(css, pos)
|
||
|
|
tokens.append(AtKeywordToken(line, column, value))
|
||
|
|
else:
|
||
|
|
tokens.append(LiteralToken(line, column, '@'))
|
||
|
|
elif c == '#':
|
||
|
|
pos += 1
|
||
|
|
if pos < length and (
|
||
|
|
css[pos] in '0123456789abcdefghijklmnopqrstuvwxyz'
|
||
|
|
'-_ABCDEFGHIJKLMNOPQRSTUVWXYZ' or
|
||
|
|
ord(css[pos]) > 0x7F or # Non-ASCII
|
||
|
|
# Valid escape:
|
||
|
|
(css[pos] == '\\' and not css.startswith('\\\n', pos))):
|
||
|
|
is_identifier = _is_ident_start(css, pos)
|
||
|
|
value, pos = _consume_ident(css, pos)
|
||
|
|
tokens.append(HashToken(line, column, value, is_identifier))
|
||
|
|
else:
|
||
|
|
tokens.append(LiteralToken(line, column, '#'))
|
||
|
|
elif c == '{':
|
||
|
|
content = []
|
||
|
|
tokens.append(CurlyBracketsBlock(line, column, content))
|
||
|
|
stack.append((tokens, end_char))
|
||
|
|
end_char = '}'
|
||
|
|
tokens = content
|
||
|
|
pos += 1
|
||
|
|
elif c == '[':
|
||
|
|
content = []
|
||
|
|
tokens.append(SquareBracketsBlock(line, column, content))
|
||
|
|
stack.append((tokens, end_char))
|
||
|
|
end_char = ']'
|
||
|
|
tokens = content
|
||
|
|
pos += 1
|
||
|
|
elif c == '(':
|
||
|
|
content = []
|
||
|
|
tokens.append(ParenthesesBlock(line, column, content))
|
||
|
|
stack.append((tokens, end_char))
|
||
|
|
end_char = ')'
|
||
|
|
tokens = content
|
||
|
|
pos += 1
|
||
|
|
elif c == end_char: # Matching }, ] or )
|
||
|
|
# The top-level end_char is None (never equal to a character),
|
||
|
|
# so we never get here if the stack is empty.
|
||
|
|
tokens, end_char = stack.pop()
|
||
|
|
pos += 1
|
||
|
|
elif c in '}])':
|
||
|
|
tokens.append(ParseError(line, column, c, 'Unmatched ' + c))
|
||
|
|
pos += 1
|
||
|
|
elif c in ('"', "'"):
|
||
|
|
value, pos, error = _consume_quoted_string(css, pos)
|
||
|
|
if value is not None:
|
||
|
|
repr = '"{}"'.format(serialize_string_value(value))
|
||
|
|
if error is not None:
|
||
|
|
repr = repr[:-1]
|
||
|
|
tokens.append(StringToken(line, column, value, repr))
|
||
|
|
if error is not None:
|
||
|
|
tokens.append(ParseError(line, column, *error))
|
||
|
|
elif css.startswith('/*', pos): # Comment
|
||
|
|
pos = css.find('*/', pos + 2)
|
||
|
|
if pos == -1:
|
||
|
|
if not skip_comments:
|
||
|
|
tokens.append(
|
||
|
|
Comment(line, column, css[token_start_pos + 2:]))
|
||
|
|
break
|
||
|
|
if not skip_comments:
|
||
|
|
tokens.append(
|
||
|
|
Comment(line, column, css[token_start_pos + 2:pos]))
|
||
|
|
pos += 2
|
||
|
|
elif css.startswith('<!--', pos):
|
||
|
|
tokens.append(LiteralToken(line, column, '<!--'))
|
||
|
|
pos += 4
|
||
|
|
elif css.startswith('||', pos):
|
||
|
|
tokens.append(LiteralToken(line, column, '||'))
|
||
|
|
pos += 2
|
||
|
|
elif c in '~|^$*':
|
||
|
|
pos += 1
|
||
|
|
if css.startswith('=', pos):
|
||
|
|
pos += 1
|
||
|
|
tokens.append(LiteralToken(line, column, c + '='))
|
||
|
|
else:
|
||
|
|
tokens.append(LiteralToken(line, column, c))
|
||
|
|
else:
|
||
|
|
tokens.append(LiteralToken(line, column, c))
|
||
|
|
pos += 1
|
||
|
|
return root
|
||
|
|
|
||
|
|
|
||
|
|
def _is_name_start(css, pos):
|
||
|
|
"""Return true if the given character is a name-start code point."""
|
||
|
|
# https://www.w3.org/TR/css-syntax-3/#name-start-code-point
|
||
|
|
c = css[pos]
|
||
|
|
return (
|
||
|
|
c in 'abcdefghijklmnopqrstuvwxyzABCDEFGHIJKLMNOPQRSTUVWXYZ_' or
|
||
|
|
ord(c) > 0x7F)
|
||
|
|
|
||
|
|
|
||
|
|
def _is_ident_start(css, pos):
|
||
|
|
"""Return True if the given position is the start of a CSS identifier."""
|
||
|
|
# https://drafts.csswg.org/css-syntax/#would-start-an-identifier
|
||
|
|
if _is_name_start(css, pos):
|
||
|
|
return True
|
||
|
|
elif css[pos] == '-':
|
||
|
|
pos += 1
|
||
|
|
return (
|
||
|
|
# Name-start code point or hyphen:
|
||
|
|
(pos < len(css) and (
|
||
|
|
_is_name_start(css, pos) or css[pos] == '-')) or
|
||
|
|
# Valid escape:
|
||
|
|
(css.startswith('\\', pos) and not css.startswith('\\\n', pos)))
|
||
|
|
elif css[pos] == '\\':
|
||
|
|
return not css.startswith('\\\n', pos)
|
||
|
|
return False
|
||
|
|
|
||
|
|
|
||
|
|
def _consume_ident(css, pos):
|
||
|
|
"""Return (unescaped_value, new_pos).
|
||
|
|
|
||
|
|
Assumes pos starts at a valid identifier. See :func:`_is_ident_start`.
|
||
|
|
|
||
|
|
"""
|
||
|
|
# http://dev.w3.org/csswg/css-syntax/#consume-a-name
|
||
|
|
chunks = []
|
||
|
|
length = len(css)
|
||
|
|
start_pos = pos
|
||
|
|
while pos < length:
|
||
|
|
c = css[pos]
|
||
|
|
if c in ('abcdefghijklmnopqrstuvwxyz-_0123456789'
|
||
|
|
'ABCDEFGHIJKLMNOPQRSTUVWXYZ') or ord(c) > 0x7F:
|
||
|
|
pos += 1
|
||
|
|
elif c == '\\' and not css.startswith('\\\n', pos):
|
||
|
|
# Valid escape
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
c, pos = _consume_escape(css, pos + 1)
|
||
|
|
chunks.append(c)
|
||
|
|
start_pos = pos
|
||
|
|
else:
|
||
|
|
break
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
return ''.join(chunks), pos
|
||
|
|
|
||
|
|
|
||
|
|
def _consume_quoted_string(css, pos):
|
||
|
|
"""Return (unescaped_value, new_pos)."""
|
||
|
|
# https://drafts.csswg.org/css-syntax/#consume-a-string-token
|
||
|
|
error = None
|
||
|
|
quote = css[pos]
|
||
|
|
assert quote in ('"', "'")
|
||
|
|
pos += 1
|
||
|
|
chunks = []
|
||
|
|
length = len(css)
|
||
|
|
start_pos = pos
|
||
|
|
while pos < length:
|
||
|
|
c = css[pos]
|
||
|
|
if c == quote:
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
pos += 1
|
||
|
|
break
|
||
|
|
elif c == '\\':
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
pos += 1
|
||
|
|
if pos < length:
|
||
|
|
if css[pos] == '\n': # Ignore escaped newlines
|
||
|
|
pos += 1
|
||
|
|
else:
|
||
|
|
c, pos = _consume_escape(css, pos)
|
||
|
|
chunks.append(c)
|
||
|
|
# else: Escaped EOF, do nothing
|
||
|
|
start_pos = pos
|
||
|
|
elif c == '\n': # Unescaped newline
|
||
|
|
return None, pos, ('bad-string', 'Bad string token')
|
||
|
|
else:
|
||
|
|
pos += 1
|
||
|
|
else:
|
||
|
|
error = ('eof-in-string', 'EOF in string')
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
return ''.join(chunks), pos, error
|
||
|
|
|
||
|
|
|
||
|
|
def _consume_escape(css, pos):
|
||
|
|
r"""Return (unescaped_char, new_pos).
|
||
|
|
|
||
|
|
Assumes a valid escape: pos is just after '\' and not followed by '\n'.
|
||
|
|
|
||
|
|
"""
|
||
|
|
# https://drafts.csswg.org/css-syntax/#consume-an-escaped-character
|
||
|
|
hex_match = _HEX_ESCAPE_RE.match(css, pos)
|
||
|
|
if hex_match:
|
||
|
|
codepoint = int(hex_match.group(1), 16)
|
||
|
|
return (
|
||
|
|
chr(codepoint) if 0 < codepoint <= sys.maxunicode else '\uFFFD',
|
||
|
|
hex_match.end())
|
||
|
|
elif pos < len(css):
|
||
|
|
return css[pos], pos + 1
|
||
|
|
else:
|
||
|
|
return '\uFFFD', pos
|
||
|
|
|
||
|
|
|
||
|
|
def _consume_url(css, pos):
|
||
|
|
"""Return (unescaped_url, new_pos)
|
||
|
|
|
||
|
|
The given pos is assumed to be just after the '(' of 'url('.
|
||
|
|
|
||
|
|
"""
|
||
|
|
error = None
|
||
|
|
length = len(css)
|
||
|
|
# https://drafts.csswg.org/css-syntax/#consume-a-url-token
|
||
|
|
# Skip whitespace
|
||
|
|
while css.startswith((' ', '\n', '\t'), pos):
|
||
|
|
pos += 1
|
||
|
|
if pos >= length: # EOF
|
||
|
|
return '', pos, ('eof-in-url', 'EOF in URL')
|
||
|
|
c = css[pos]
|
||
|
|
if c in ('"', "'"):
|
||
|
|
value, pos, error = _consume_quoted_string(css, pos)
|
||
|
|
elif c == ')':
|
||
|
|
return '', pos + 1, error
|
||
|
|
else:
|
||
|
|
chunks = []
|
||
|
|
start_pos = pos
|
||
|
|
while 1:
|
||
|
|
if pos >= length: # EOF
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
return ''.join(chunks), pos, ('eof-in-url', 'EOF in URL')
|
||
|
|
c = css[pos]
|
||
|
|
if c == ')':
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
pos += 1
|
||
|
|
return ''.join(chunks), pos, error
|
||
|
|
elif c in ' \n\t':
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
value = ''.join(chunks)
|
||
|
|
pos += 1
|
||
|
|
break
|
||
|
|
elif c == '\\' and not css.startswith('\\\n', pos):
|
||
|
|
# Valid escape
|
||
|
|
chunks.append(css[start_pos:pos])
|
||
|
|
c, pos = _consume_escape(css, pos + 1)
|
||
|
|
chunks.append(c)
|
||
|
|
start_pos = pos
|
||
|
|
elif (c in
|
||
|
|
'"\'('
|
||
|
|
# https://drafts.csswg.org/css-syntax/#non-printable-character
|
||
|
|
'\x00\x01\x02\x03\x04\x05\x06\x07\x08\x0b\x0e'
|
||
|
|
'\x0f\x10\x11\x12\x13\x14\x15\x16\x17\x18\x19'
|
||
|
|
'\x1a\x1b\x1c\x1d\x1e\x1f\x7f'):
|
||
|
|
value = None # Parse error
|
||
|
|
pos += 1
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
pos += 1
|
||
|
|
|
||
|
|
if value is not None:
|
||
|
|
while css.startswith((' ', '\n', '\t'), pos):
|
||
|
|
pos += 1
|
||
|
|
if pos < length:
|
||
|
|
if css[pos] == ')':
|
||
|
|
return value, pos + 1, error
|
||
|
|
else:
|
||
|
|
if error is None:
|
||
|
|
error = ('eof-in-url', 'EOF in URL')
|
||
|
|
return value, pos, error
|
||
|
|
|
||
|
|
# https://drafts.csswg.org/css-syntax/#consume-the-remnants-of-a-bad-url0
|
||
|
|
while pos < length:
|
||
|
|
if css.startswith('\\)', pos):
|
||
|
|
pos += 2
|
||
|
|
elif css[pos] == ')':
|
||
|
|
pos += 1
|
||
|
|
break
|
||
|
|
else:
|
||
|
|
pos += 1
|
||
|
|
return None, pos, ('bad-url', 'bad URL token')
|
||
|
|
|
||
|
|
|
||
|
|
def _consume_unicode_range(css, pos):
|
||
|
|
"""Return (range, new_pos)
|
||
|
|
|
||
|
|
The given pos is assume to be just after the '+' of 'U+' or 'u+'.
|
||
|
|
|
||
|
|
"""
|
||
|
|
# https://drafts.csswg.org/css-syntax/#consume-a-unicode-range-token
|
||
|
|
length = len(css)
|
||
|
|
start_pos = pos
|
||
|
|
max_pos = min(pos + 6, length)
|
||
|
|
while pos < max_pos and css[pos] in '0123456789abcdefABCDEF':
|
||
|
|
pos += 1
|
||
|
|
start = css[start_pos:pos]
|
||
|
|
|
||
|
|
start_pos = pos
|
||
|
|
# Same max_pos as before: total of hex digits and question marks <= 6
|
||
|
|
while pos < max_pos and css[pos] == '?':
|
||
|
|
pos += 1
|
||
|
|
question_marks = pos - start_pos
|
||
|
|
|
||
|
|
if question_marks:
|
||
|
|
end = start + 'F' * question_marks
|
||
|
|
start = start + '0' * question_marks
|
||
|
|
elif (pos + 1 < length and css[pos] == '-' and
|
||
|
|
css[pos + 1] in '0123456789abcdefABCDEF'):
|
||
|
|
pos += 1
|
||
|
|
start_pos = pos
|
||
|
|
max_pos = min(pos + 6, length)
|
||
|
|
while pos < max_pos and css[pos] in '0123456789abcdefABCDEF':
|
||
|
|
pos += 1
|
||
|
|
end = css[start_pos:pos]
|
||
|
|
else:
|
||
|
|
end = start
|
||
|
|
return int(start, 16), int(end, 16), pos
|