1
2
3 r"""
4 ==============
5 CSS Minifier
6 ==============
7
8 CSS Minifier.
9
10 The minifier is based on the semantics of the `YUI compressor`_\\, which
11 itself is based on `the rule list by Isaac Schlueter`_\\.
12
13 :Copyright:
14
15 Copyright 2011 - 2014
16 Andr\xe9 Malo or his licensors, as applicable
17
18 :License:
19
20 Licensed under the Apache License, Version 2.0 (the "License");
21 you may not use this file except in compliance with the License.
22 You may obtain a copy of the License at
23
24 http://www.apache.org/licenses/LICENSE-2.0
25
26 Unless required by applicable law or agreed to in writing, software
27 distributed under the License is distributed on an "AS IS" BASIS,
28 WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
29 See the License for the specific language governing permissions and
30 limitations under the License.
31
32 This module is a re-implementation aiming for speed instead of maximum
33 compression, so it can be used at runtime (rather than during a preprocessing
34 step). RCSSmin does syntactical compression only (removing spaces, comments
35 and possibly semicolons). It does not provide semantic compression (like
36 removing empty blocks, collapsing redundant properties etc). It does, however,
37 support various CSS hacks (by keeping them working as intended).
38
39 Here's a feature list:
40
41 - Strings are kept, except that escaped newlines are stripped
42 - Space/Comments before the very end or before various characters are
43 stripped: ``:{});=>+],!`` (The colon (``:``) is a special case, a single
44 space is kept if it's outside a ruleset.)
45 - Space/Comments at the very beginning or after various characters are
46 stripped: ``{}(=:>+[,!``
47 - Optional space after unicode escapes is kept, resp. replaced by a simple
48 space
49 - whitespaces inside ``url()`` definitions are stripped
50 - Comments starting with an exclamation mark (``!``) can be kept optionally.
51 - All other comments and/or whitespace characters are replaced by a single
52 space.
53 - Multiple consecutive semicolons are reduced to one
54 - The last semicolon within a ruleset is stripped
55 - CSS Hacks supported:
56
57 - IE7 hack (``>/**/``)
58 - Mac-IE5 hack (``/*\\*/.../**/``)
59 - The boxmodelhack is supported naturally because it relies on valid CSS2
60 strings
61 - Between ``:first-line`` and the following comma or curly brace a space is
62 inserted. (apparently it's needed for IE6)
63 - Same for ``:first-letter``
64
65 rcssmin.c is a reimplementation of rcssmin.py in C and improves runtime up to
66 factor 100 or so (depending on the input). docs/BENCHMARKS in the source
67 distribution contains the details.
68
69 Both python 2 (>= 2.4) and python 3 are supported.
70
71 .. _YUI compressor: https://github.com/yui/yuicompressor/
72
73 .. _the rule list by Isaac Schlueter: https://github.com/isaacs/cssmin/
74 """
75 if __doc__:
76
77 __doc__ = __doc__.encode('ascii').decode('unicode_escape')
78 __author__ = r"Andr\xe9 Malo".encode('ascii').decode('unicode_escape')
79 __docformat__ = "restructuredtext en"
80 __license__ = "Apache License, Version 2.0"
81 __version__ = '1.0.5'
82 __all__ = ['cssmin']
83
84 import re as _re
85
86
88 """
89 Generate CSS minifier.
90
91 :Parameters:
92 `python_only` : ``bool``
93 Use only the python variant. If true, the c extension is not even
94 tried to be loaded.
95
96 :Return: Minifier
97 :Rtype: ``callable``
98 """
99
100
101 if not python_only:
102 try:
103 import _rcssmin
104 except ImportError:
105 pass
106 else:
107 return _rcssmin.cssmin
108
109 nl = r'(?:[\n\f]|\r\n?)'
110 spacechar = r'[\r\n\f\040\t]'
111
112 unicoded = r'[0-9a-fA-F]{1,6}(?:[\040\n\t\f]|\r\n?)?'
113 escaped = r'[^\n\r\f0-9a-fA-F]'
114 escape = r'(?:\\(?:%(unicoded)s|%(escaped)s))' % locals()
115
116 nmchar = r'[^\000-\054\056\057\072-\100\133-\136\140\173-\177]'
117
118
119
120
121
122 comment = r'(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)'
123
124
125 _bang_comment = r'(?:/\*(!?)[^*]*\*+(?:[^/*][^*]*\*+)*/)'
126
127 string1 = \
128 r'(?:\047[^\047\\\r\n\f]*(?:\\[^\r\n\f][^\047\\\r\n\f]*)*\047)'
129 string2 = r'(?:"[^"\\\r\n\f]*(?:\\[^\r\n\f][^"\\\r\n\f]*)*")'
130 strings = r'(?:%s|%s)' % (string1, string2)
131
132 nl_string1 = \
133 r'(?:\047[^\047\\\r\n\f]*(?:\\(?:[^\r]|\r\n?)[^\047\\\r\n\f]*)*\047)'
134 nl_string2 = r'(?:"[^"\\\r\n\f]*(?:\\(?:[^\r]|\r\n?)[^"\\\r\n\f]*)*")'
135 nl_strings = r'(?:%s|%s)' % (nl_string1, nl_string2)
136
137 uri_nl_string1 = r'(?:\047[^\047\\]*(?:\\(?:[^\r]|\r\n?)[^\047\\]*)*\047)'
138 uri_nl_string2 = r'(?:"[^"\\]*(?:\\(?:[^\r]|\r\n?)[^"\\]*)*")'
139 uri_nl_strings = r'(?:%s|%s)' % (uri_nl_string1, uri_nl_string2)
140
141 nl_escaped = r'(?:\\%(nl)s)' % locals()
142
143 space = r'(?:%(spacechar)s|%(comment)s)' % locals()
144
145 ie7hack = r'(?:>/\*\*/)'
146
147 uri = (r'(?:'
148
149 r'(?:[^\000-\040"\047()\\\177]*'
150 r'(?:%(escape)s[^\000-\040"\047()\\\177]*)*)'
151 r'(?:'
152 r'(?:%(spacechar)s+|%(nl_escaped)s+)'
153 r'(?:'
154 r'(?:[^\000-\040"\047()\\\177]|%(escape)s|%(nl_escaped)s)'
155 r'[^\000-\040"\047()\\\177]*'
156 r'(?:%(escape)s[^\000-\040"\047()\\\177]*)*'
157 r')+'
158 r')*'
159 r')') % locals()
160
161 nl_unesc_sub = _re.compile(nl_escaped).sub
162
163 uri_space_sub = _re.compile((
164 r'(%(escape)s+)|%(spacechar)s+|%(nl_escaped)s+'
165 ) % locals()).sub
166 uri_space_subber = lambda m: m.groups()[0] or ''
167
168 space_sub_simple = _re.compile((
169 r'[\r\n\f\040\t;]+|(%(comment)s+)'
170 ) % locals()).sub
171 space_sub_banged = _re.compile((
172 r'[\r\n\f\040\t;]+|(%(_bang_comment)s+)'
173 ) % locals()).sub
174
175 post_esc_sub = _re.compile(r'[\r\n\f\t]+').sub
176
177 main_sub = _re.compile((
178
179 r'([^\\"\047u>@\r\n\f\040\t/;:{}]+)'
180 r'|(?<=[{}(=:>+[,!])(%(space)s+)'
181 r'|^(%(space)s+)'
182 r'|(%(space)s+)(?=(([:{});=>+\],!])|$)?)'
183 r'|;(%(space)s*(?:;%(space)s*)*)(?=(\})?)'
184 r'|(\{)'
185 r'|(\})'
186 r'|(%(strings)s)'
187 r'|(?<!%(nmchar)s)url\(%(spacechar)s*('
188 r'%(uri_nl_strings)s'
189 r'|%(uri)s'
190 r')%(spacechar)s*\)'
191 r'|(@(?:'
192 r'[mM][eE][dD][iI][aA]'
193 r'|[sS][uU][pP][pP][oO][rR][tT][sS]'
194 r'|[dD][oO][cC][uU][mM][eE][nN][tT]'
195 r'|(?:-(?:'
196 r'[wW][eE][bB][kK][iI][tT]|[mM][oO][zZ]|[oO]|[mM][sS]'
197 r')-)?'
198 r'[kK][eE][yY][fF][rR][aA][mM][eE][sS]'
199 r'))(?!%(nmchar)s)'
200 r'|(%(ie7hack)s)(%(space)s*)'
201 r'|(:[fF][iI][rR][sS][tT]-[lL]'
202 r'(?:[iI][nN][eE]|[eE][tT][tT][eE][rR]))'
203 r'(%(space)s*)(?=[{,])'
204 r'|(%(nl_strings)s)'
205 r'|(%(escape)s[^\\"\047u>@\r\n\f\040\t/;:{}]*)'
206 ) % locals()).sub
207
208
209
210 def main_subber(keep_bang_comments):
211 """ Make main subber """
212 in_macie5, in_rule, at_group = [0], [0], [0]
213
214 if keep_bang_comments:
215 space_sub = space_sub_banged
216
217 def space_subber(match):
218 """ Space|Comment subber """
219 if match.lastindex:
220 group1, group2 = match.group(1, 2)
221 if group2:
222 if group1.endswith(r'\*/'):
223 in_macie5[0] = 1
224 else:
225 in_macie5[0] = 0
226 return group1
227 elif group1:
228 if group1.endswith(r'\*/'):
229 if in_macie5[0]:
230 return ''
231 in_macie5[0] = 1
232 return r'/*\*/'
233 elif in_macie5[0]:
234 in_macie5[0] = 0
235 return '/**/'
236 return ''
237 else:
238 space_sub = space_sub_simple
239
240 def space_subber(match):
241 """ Space|Comment subber """
242 if match.lastindex:
243 if match.group(1).endswith(r'\*/'):
244 if in_macie5[0]:
245 return ''
246 in_macie5[0] = 1
247 return r'/*\*/'
248 elif in_macie5[0]:
249 in_macie5[0] = 0
250 return '/**/'
251 return ''
252
253 def fn_space_post(group):
254 """ space with token after """
255 if group(5) is None or (
256 group(6) == ':' and not in_rule[0] and not at_group[0]):
257 return ' ' + space_sub(space_subber, group(4))
258 return space_sub(space_subber, group(4))
259
260 def fn_semicolon(group):
261 """ ; handler """
262 return ';' + space_sub(space_subber, group(7))
263
264 def fn_semicolon2(group):
265 """ ; handler """
266 if in_rule[0]:
267 return space_sub(space_subber, group(7))
268 return ';' + space_sub(space_subber, group(7))
269
270 def fn_open(_):
271 """ { handler """
272 if at_group[0]:
273 at_group[0] -= 1
274 else:
275 in_rule[0] = 1
276 return '{'
277
278 def fn_close(_):
279 """ } handler """
280 in_rule[0] = 0
281 return '}'
282
283 def fn_at_group(group):
284 """ @xxx group handler """
285 at_group[0] += 1
286 return group(13)
287
288 def fn_ie7hack(group):
289 """ IE7 Hack handler """
290 if not in_rule[0] and not at_group[0]:
291 in_macie5[0] = 0
292 return group(14) + space_sub(space_subber, group(15))
293 return '>' + space_sub(space_subber, group(15))
294
295 table = (
296
297 None,
298 None,
299 None,
300 None,
301 fn_space_post,
302 fn_space_post,
303 fn_space_post,
304 fn_semicolon,
305 fn_semicolon2,
306 fn_open,
307 fn_close,
308 lambda g: g(11),
309 lambda g: 'url(%s)' % uri_space_sub(uri_space_subber, g(12)),
310
311 fn_at_group,
312 None,
313 fn_ie7hack,
314 None,
315 lambda g: g(16) + ' ' + space_sub(space_subber, g(17)),
316
317
318
319 lambda g: nl_unesc_sub('', g(18)),
320 lambda g: post_esc_sub(' ', g(19)),
321 )
322
323 def func(match):
324 """ Main subber """
325 idx, group = match.lastindex, match.group
326 if idx > 3:
327 return table[idx](group)
328
329
330 elif idx == 1:
331 return group(1)
332
333 return space_sub(space_subber, group(idx))
334
335 return func
336
337 def cssmin(style, keep_bang_comments=False):
338 """
339 Minify CSS.
340
341 :Parameters:
342 `style` : ``str``
343 CSS to minify
344
345 `keep_bang_comments` : ``bool``
346 Keep comments starting with an exclamation mark? (``/*!...*/``)
347
348 :Return: Minified style
349 :Rtype: ``str``
350 """
351 return main_sub(main_subber(keep_bang_comments), style)
352
353 return cssmin
354
355 cssmin = _make_cssmin()
356
357
358 if __name__ == '__main__':
360 """ Main """
361 import sys as _sys
362 keep_bang_comments = (
363 '-b' in _sys.argv[1:]
364 or '-bp' in _sys.argv[1:]
365 or '-pb' in _sys.argv[1:]
366 )
367 if '-p' in _sys.argv[1:] or '-bp' in _sys.argv[1:] \
368 or '-pb' in _sys.argv[1:]:
369 global cssmin
370 cssmin = _make_cssmin(python_only=True)
371 _sys.stdout.write(cssmin(
372 _sys.stdin.read(), keep_bang_comments=keep_bang_comments
373 ))
374 main()
375