deb-python-csscompressor/csscompressor/__init__.py

564 lines
20 KiB
Python

##
# Portions Copyright (c) 2013 Sprymix Inc.
# Author of python port: Yury Selivanov - http://sprymix.com
#
# Author: Julien Lecomte - http://www.julienlecomte.net/
# Author: Isaac Schlueter - http://foohack.com/
# Author: Stoyan Stefanov - http://phpied.com/
# Contributor: Dan Beam - http://danbeam.org/
# Contributor: w.Tayyeb - http://tayyeb.info/
# Portions Copyright (c) 2011-2013 Yahoo! Inc. All rights reserved.
# LICENSE: BSD (revised)
##
__all__ = ('compress', 'compress_partitioned')
__version__ = '0.9.4'
import re
_url_re = re.compile(r'''(url)\s*\(\s*(['"]?)data\:''', re.I)
_calc_re = re.compile(r'(calc)\s*\(', re.I)
_hsl_re = re.compile(r'(hsl|hsla)\s*\(', re.I)
_ws_re = re.compile(r'\s+')
_str_re = re.compile(r'''("([^\\"]|\\.|\\)*")|('([^\\']|\\.|\\)*')''')
_yui_comment_re = re.compile(r'___YUICSSMIN_PRESERVE_CANDIDATE_COMMENT_(?P<num>\d+)___')
_ms_filter_re = re.compile(r'progid\:DXImageTransform\.Microsoft\.Alpha\(Opacity=', re.I)
_spaces1_re = re.compile(r'(^|\})(([^\{:])+:)+([^\{]*\{)')
_spaces2_re = re.compile(r'\s+([!{};:>+\(\)\],])')
_ie6special_re = re.compile(r':first-(line|letter)(\{|,)', re.I)
_charset1_re = re.compile(r'^(.*)(@charset)\s+("[^"]*";)', re.I)
_charset2_re = re.compile(r'^((\s*)(@charset)\s+([^;]+;\s*))+', re.I)
_dirs_re = re.compile(r'''@(font-face|import|
(?:-(?:atsc|khtml|moz|ms|o|wap|webkit)-)?
keyframe|media|page|namespace)''',
re.I | re.X)
_pseudo_re = re.compile(r''':(active|after|before|checked|disabled|empty|enabled|
first-(?:child|of-type)|focus|hover|last-(?:child|of-type)|
link|only-(?:child|of-type)|root|:selection|target|visited)''',
re.I | re.X)
_common_funcs_re = re.compile(r''':(lang|not|nth-child|nth-last-child|nth-last-of-type|
nth-of-type|(?:-(?:moz|webkit)-)?any)\(''', re.I | re.X)
_common_val_funcs_re = re.compile(r'''([:,\(\s]\s*)(attr|color-stop|from|rgba|to|url|
(?:-(?:atsc|khtml|moz|ms|o|wap|webkit)-)?
(?:calc|max|min|(?:repeating-)?
(?:linear|radial)-gradient)|-webkit-gradient)''',
re.I | re.X)
_space_and_re = re.compile(r'\band\(', re.I)
_space_after_re = re.compile(r'([!{}:;>+\(\[,])\s+')
_semi_re = re.compile(r';+}')
_zero_fmt_spec_re = re.compile(r'''(\s|:|\(|,)(?:0?\.)?0
(?:px|em|%|in|cm|mm|pc|pt|ex|deg|g?rad|k?hz)''',
re.I | re.X)
_zero_req_unit_re = re.compile(r'''(\s|:|\(|,)(?:0?\.)?0
(m?s)''', re.I | re.X)
_bg_pos_re = re.compile(r'''(background-position|webkit-mask-position|transform-origin|
webkit-transform-origin|moz-transform-origin|o-transform-origin|
ms-transform-origin):0(;|})''', re.I | re.X)
_quad_0_re = re.compile(r':0 0 0 0(;|})')
_trip_0_re = re.compile(r':0 0 0(;|})')
_coup_0_re = re.compile(r':0 0(;|})')
_point_float_re = re.compile(r'(:|\s)0+\.(\d+)')
_point_float_neg_re = re.compile(r'(:|\s)-0+\.(\d+)')
_point_float_pos_re = re.compile(r'(:|\s)\+(\d+)+\.(\d+)')
_border_re = re.compile(r'''(border|border-top|border-right|border-bottom|
border-left|outline|background):none(;|})''', re.I | re.X)
_o_px_ratio_re = re.compile(r'\(([\-A-Za-z]+):([0-9]+)\/([0-9]+)\)')
_empty_rules_re = re.compile(r'[^\}\{/;]+\{\}')
_many_semi_re = re.compile(';;+')
_rgb_re = re.compile(r'rgb\s*\(\s*([0-9,\s]+)\s*\)')
_hex_color_re = re.compile(r'''(\=\s*?["']?)?
\#([0-9a-fA-F])([0-9a-fA-F])
([0-9a-fA-F])([0-9a-fA-F])
([0-9a-fA-F])([0-9a-fA-F])
(\}|[^0-9a-fA-F{][^{]*?\})''', re.X)
_ie_matrix_re = re.compile(r'\s*filter:\s*progid:DXImageTransform\.Microsoft\.Matrix\(([^\)]+)\);')
_colors_map = {
'f00': 'red',
'000080': 'navy',
'808080': 'gray',
'808000': 'olive',
'800080': 'purple',
'c0c0c0': 'silver',
'008080': 'teal',
'ffa500': 'orange',
'800000': 'maroon'
}
_colors_re = re.compile(r'(:|\s)' + '(\\#(' + '|'.join(_colors_map.keys()) + '))' + r'(;|})', re.I)
def _preserve_call_tokens(css, regexp, preserved_tokens, remove_ws=False):
max_idx = len(css) - 1
append_idx = 0
sb = []
for match in regexp.finditer(css):
name = match.group(1)
start_idx = match.start(0) + len(name) + 1 # "len" of "url("
term = match.group(2) if match.lastindex > 1 else None
if not term:
term = ')'
found_term = False
end_idx = match.end(0) - 1
while not found_term and (end_idx + 1) <= max_idx:
end_idx = css.find(term, end_idx + 1)
if end_idx > 0:
if css[end_idx - 1] != '\\':
found_term = True
if term != ')':
end_idx = css.find(')', end_idx)
else:
raise ValueError('malformed css')
sb.append(css[append_idx:match.start(0)])
assert found_term
token = css[start_idx:end_idx]
if remove_ws:
token = _ws_re.sub('', token)
preserver = ('{0}(___YUICSSMIN_PRESERVED_TOKEN_{1}___)'
.format(name, len(preserved_tokens)))
preserved_tokens.append(token)
sb.append(preserver)
append_idx = end_idx + 1
sb.append(css[append_idx:])
return ''.join(sb)
def _compress_rgb_calls(css):
# Shorten colors from rgb(51,102,153) to #336699
# This makes it more likely that it'll get further compressed in the next step.
def _replace(match):
rgb_colors = match.group(1).split(',')
result = '#'
for comp in rgb_colors:
comp = int(comp)
if comp < 16:
result += '0'
if comp > 255:
comp = 255
result += hex(comp)[2:].lower()
return result
return _rgb_re.sub(_replace, css)
def _compress_hex_colors(css):
# Shorten colors from #AABBCC to #ABC. Note that we want to make sure
# the color is not preceded by either ", " or =. Indeed, the property
# filter: chroma(color="#FFFFFF");
# would become
# filter: chroma(color="#FFF");
# which makes the filter break in IE.
# We also want to make sure we're only compressing #AABBCC patterns inside { },
# not id selectors ( #FAABAC {} )
# We also want to avoid compressing invalid values (e.g. #AABBCCD to #ABCD)
buf = []
index = 0
while True:
match = _hex_color_re.search(css, index)
if not match:
break
buf.append(css[index:match.start(0)])
if match.group(1):
# Restore, as is. Compression will break filters
buf.append(match.group(1) + ('#' + match.group(2) + match.group(3) + match.group(4) +
match.group(5) + match.group(6) + match.group(7)))
else:
if (match.group(2).lower() == match.group(3).lower() and
match.group(4).lower() == match.group(5).lower() and
match.group(6).lower() == match.group(7).lower()):
buf.append('#' + (match.group(2) + match.group(4) + match.group(6)).lower())
else:
buf.append('#' + (match.group(2) + match.group(3) + match.group(4) +
match.group(5) + match.group(6) + match.group(7)).lower())
index = match.end(7)
buf.append(css[index:])
return ''.join(buf)
def _compress(css, max_linelen=0, preserve_exclamation_comments=True):
start_idx = end_idx = 0
total_len = len(css)
preserved_tokens = []
css = _preserve_call_tokens(css, _url_re, preserved_tokens, remove_ws=True)
css = _preserve_call_tokens(css, _calc_re, preserved_tokens, remove_ws=False)
css = _preserve_call_tokens(css, _hsl_re, preserved_tokens, remove_ws=True)
# Collect all comments blocks...
comments = []
while True:
start_idx = css.find('/*', start_idx)
if start_idx < 0:
break
suffix = ''
end_idx = css.find('*/', start_idx + 2)
if end_idx < 0:
end_idx = total_len
suffix = '*/'
token = css[start_idx + 2:end_idx]
comments.append(token)
css = (css[:start_idx + 2] +
'___YUICSSMIN_PRESERVE_CANDIDATE_COMMENT_{0}___'.format(len(comments)-1) +
css[end_idx:] + suffix)
start_idx += 2
# preserve strings so their content doesn't get accidentally minified
def _replace(match):
token = match.group(0)
quote = token[0]
token = token[1:-1]
# maybe the string contains a comment-like substring?
# one, maybe more? put'em back then
if '___YUICSSMIN_PRESERVE_CANDIDATE_COMMENT_' in token:
token = _yui_comment_re.sub(lambda match: comments[int(match.group('num'))], token)
token = _ms_filter_re.sub('alpha(opacity=', token)
preserved_tokens.append(token)
return (quote +
'___YUICSSMIN_PRESERVED_TOKEN_{0}___'.format(len(preserved_tokens)-1) +
quote)
css = _str_re.sub(_replace, css)
# strings are safe, now wrestle the comments
comments_iter = iter(comments)
for i, token in enumerate(comments_iter):
placeholder = "___YUICSSMIN_PRESERVE_CANDIDATE_COMMENT_{0}___".format(i)
# ! in the first position of the comment means preserve
# so push to the preserved tokens while stripping the !
if preserve_exclamation_comments and token.startswith('!'):
preserved_tokens.append(token)
css = css.replace(placeholder, '___YUICSSMIN_PRESERVED_TOKEN_{0}___'.
format(len(preserved_tokens)-1))
continue
# \ in the last position looks like hack for Mac/IE5
# shorten that to /*\*/ and the next one to /**/
if token.endswith('\\'):
preserved_tokens.append('\\')
css = css.replace(placeholder,
'___YUICSSMIN_PRESERVED_TOKEN_{0}___'.format(len(preserved_tokens)-1))
# attn: advancing the loop
next(comments_iter)
preserved_tokens.append('')
css = css.replace('___YUICSSMIN_PRESERVE_CANDIDATE_COMMENT_{0}___'.format(i+1),
'___YUICSSMIN_PRESERVED_TOKEN_{0}___'.format(len(preserved_tokens)-1))
continue
# keep empty comments after child selectors (IE7 hack)
# e.g. html >/**/ body
if not token:
start_idx = css.find(placeholder)
if start_idx > 2:
if css[start_idx-3] == '>':
preserved_tokens.append('')
css = css.replace(placeholder,
'___YUICSSMIN_PRESERVED_TOKEN_{0}___'.
format(len(preserved_tokens)-1))
# in all other cases kill the comment
css = css.replace('/*{0}*/'.format(placeholder), '')
# Normalize all whitespace strings to single spaces. Easier to work with that way.
css = _ws_re.sub(' ', css)
def _replace(match):
token = match.group(1)
preserved_tokens.append(token);
return ('filter:progid:DXImageTransform.Microsoft.Matrix(' +
'___YUICSSMIN_PRESERVED_TOKEN_{0}___);'.format(len(preserved_tokens)-1))
css = _ie_matrix_re.sub(_replace, css)
# remove + sign where it is before a float +0.1 +2.34
css = _point_float_pos_re.sub(r'\1\2.\3', css)
# Remove the spaces before the things that should not have spaces before them.
# But, be careful not to turn "p :link {...}" into "p:link{...}"
# Swap out any pseudo-class colons with the token, and then swap back.
css = _spaces1_re.sub(lambda match: match.group(0) \
.replace(':', '___YUICSSMIN_PSEUDOCLASSCOLON___'), css)
css = _spaces2_re.sub(lambda match: match.group(1), css)
# Restore spaces for !important
css = css.replace('!important', ' !important');
# bring back the colon
css = css.replace('___YUICSSMIN_PSEUDOCLASSCOLON___', ':')
# retain space for special IE6 cases
css = _ie6special_re.sub(
lambda match: ':first-{0} {1}'.format(match.group(1).lower(), match.group(2)),
css)
# no space after the end of a preserved comment
css = css.replace('*/ ', '*/')
# If there are multiple @charset directives, push them to the top of the file.
css = _charset1_re.sub(lambda match: match.group(2).lower() + \
' ' + match.group(3) + match.group(1),
css)
# When all @charset are at the top, remove the second and after (as they are completely ignored)
css = _charset2_re.sub(lambda match: match.group(2) + \
match.group(3).lower() + ' ' + match.group(4),
css)
# lowercase some popular @directives (@charset is done right above)
css = _dirs_re.sub(lambda match: '@' + match.group(1).lower(), css)
# lowercase some more common pseudo-elements
css = _pseudo_re.sub(lambda match: ':' + match.group(1).lower(), css)
# lowercase some more common functions
css = _common_funcs_re.sub(lambda match: ':' + match.group(1).lower() + '(', css)
# lower case some common function that can be values
# NOTE: rgb() isn't useful as we replace with #hex later, as well as and()
# is already done for us right after this
css = _common_val_funcs_re.sub(lambda match: match.group(1) + match.group(2).lower(), css)
# Put the space back in some cases, to support stuff like
# @media screen and (-webkit-min-device-pixel-ratio:0){
css = _space_and_re.sub('and (', css)
# Remove the spaces after the things that should not have spaces after them.
css = _space_after_re.sub(r'\1', css)
# remove unnecessary semicolons
css = _semi_re.sub('}', css)
# Replace 0(px,em,%) with 0.
css = _zero_fmt_spec_re.sub(lambda match: match.group(1) + '0', css)
# Replace 0.0(m,ms) or .0(m,ms) with 0(m,ms)
css = _zero_req_unit_re.sub(lambda match: match.group(1) + '0' + match.group(2), css)
# Replace 0 0 0 0; with 0.
css = _quad_0_re.sub(r':0\1', css)
css = _trip_0_re.sub(r':0\1', css)
css = _coup_0_re.sub(r':0\1', css)
# Replace background-position:0; with background-position:0 0;
# same for transform-origin
css = _bg_pos_re.sub(lambda match: match.group(1).lower() + ':0 0' + match.group(2), css)
# Replace 0.6 to .6, but only when preceded by : or a white-space
css = _point_float_re.sub(r'\1.\2', css)
# Replace -0.6 to -.6, but only when preceded by : or a white-space
css = _point_float_neg_re.sub(r'\1-.\2', css)
css = _compress_rgb_calls(css)
css = _compress_hex_colors(css)
# Replace #f00 -> red; other short color keywords
css = _colors_re.sub(lambda match: match.group(1) + _colors_map[match.group(3).lower()] +
match.group(4),
css)
# border: none -> border:0
css = _border_re.sub(lambda match: match.group(1).lower() + ':0' + match.group(2), css)
# shorter opacity IE filter
css = _ms_filter_re.sub('alpha(opacity=', css)
# Find a fraction that is used for Opera's -o-device-pixel-ratio query
# Add token to add the "\" back in later
css = _o_px_ratio_re.sub(r'\1:\2___YUI_QUERY_FRACTION___\3', css)
# Remove empty rules.
css = _empty_rules_re.sub('', css)
# Add "\" back to fix Opera -o-device-pixel-ratio query
css = css.replace('___YUI_QUERY_FRACTION___', '/')
if max_linelen and len(css) > max_linelen:
buf = []
start_pos = 0
while True:
buf.append(css[start_pos:start_pos + max_linelen])
start_pos += max_linelen
while start_pos < len(css):
if css[start_pos] == '}':
buf.append('}\n')
start_pos += 1
break
else:
buf.append(css[start_pos])
start_pos += 1
if start_pos >= len(css):
break
css = ''.join(buf)
# Replace multiple semi-colons in a row by a single one
# See SF bug #1980989
css = _many_semi_re.sub(';', css)
return css, preserved_tokens
def _apply_preserved(css, preserved_tokens):
# restore preserved comments and strings
for i, token in reversed(tuple(enumerate(preserved_tokens))):
css = css.replace('___YUICSSMIN_PRESERVED_TOKEN_{0}___'.format(i), token)
css = css.strip()
return css
def compress(css, max_linelen=0, preserve_exclamation_comments=True):
"""Compress given CSS stylesheet.
Parameters:
- css : str
An str with CSS rules.
- max_linelen : int = 0
Some source control tools don't like it when files containing lines longer
than, say 8000 characters, are checked in. This option is used in
that case to split long lines after a specific column.
- preserve_exclamation_comments : boolean = True
Some stylesheets contain /*! ... */ comment block which used for copyright
notices or else. By default compress dont remove them like other comment
blocks. It will lead to bigger file size. but once you decide to remove
them just set this parameter to False.
Returns a ``str`` object with compressed CSS.
"""
css, preserved_tokens = _compress(css, max_linelen=max_linelen, preserve_exclamation_comments=preserve_exclamation_comments)
css = _apply_preserved(css, preserved_tokens)
return css
def compress_partitioned(css,
max_linelen=0,
max_rules_per_file=4000,
preserve_exclamation_comments=True):
"""Compress given CSS stylesheet into a set of files.
Parameters:
- max_linelen : int = 0
Has the same meaning as for "compress()" function.
- max_rules_per_file : int = 0
Internet Explorers <= 9 have an artificial max number of rules per CSS
file (4096; http://blogs.msdn.com/b/ieinternals/archive/2011/05/14/10164546.aspx)
When ``max_rules_per_file`` is a positive number, the function *always* returns
a list of ``str`` objects, each limited to contain less than the passed number
of rules.
- preserve_exclamation_comments : boolean = True
Has the same meaning as for "compress()" function.
Always returns a ``list`` of ``str`` objects with compressed CSS.
"""
assert max_rules_per_file > 0
css, preserved_tokens = _compress(css, max_linelen=max_linelen, preserve_exclamation_comments=preserve_exclamation_comments)
css = css.strip()
bufs = []
buf = []
rules = 0
while css:
if rules >= max_rules_per_file:
bufs.append(''.join(buf))
rules = 0
buf = []
nested = 0
while True:
op_idx = css.find('{')
cl_idx = css.find('}')
if cl_idx < 0:
raise ValueError('malformed CSS: non-balanced curly-braces')
if op_idx < 0 or cl_idx < op_idx: # ... } ... { ...
nested -= 1
if nested < 0:
raise ValueError('malformed CSS: non-balanced curly-braces')
buf.append(css[:cl_idx+1])
css = css[cl_idx+1:]
if not nested: # closing rules
break
else: # ... { ... } ...
nested += 1
rule_line = css[:op_idx+1]
buf.append(rule_line)
css = css[op_idx+1:]
rules += rule_line.count(',') + 1
bufs.append(''.join(buf))
bufs = [_apply_preserved(buf, preserved_tokens) for buf in bufs]
return bufs