SP/web2py/gluon/contrib/minify/jsmin.py
Saturneic 064f602b1a Add.
2018-10-25 23:33:13 +08:00

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Python

#!/usr/bin/env python
# -*- coding: ascii -*-
#
# Copyright 2011
# Andr\xe9 Malo or his licensors, as applicable
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
# http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.
r"""
=====================
Javascript Minifier
=====================
Javascript Minifier based on `jsmin.c by Douglas Crockford`_\.
This module is a re-implementation based on the semantics of jsmin.c. Usually
it produces the same results. It differs in the following ways:
- there is no error detection: unterminated string, regex and comment
literals are treated as regular javascript code and minified as such.
- Control characters inside string and regex literals are left untouched; they
are not converted to spaces (nor to \n)
- Newline characters are not allowed inside string and regex literals, except
for line continuations in string literals (ECMA-5).
- "return /regex/" is recognized correctly.
- rjsmin does not handle streams, but only complete strings. (However, the
module provides a "streamy" interface).
Besides the list above it differs from direct python ports of jsmin.c in
speed. Since most parts of the logic are handled by the regex engine it's way
faster than the original python port by Baruch Even. The speed factor varies
between about 6 and 55 depending on input and python version (it gets faster
the more compressed the input already is). Compared to the speed-refactored
python port by Dave St.Germain the performance gain is less dramatic but still
between 1.2 and 7. See the docs/BENCHMARKS file for details.
rjsmin.c is a reimplementation of rjsmin.py in C and speeds it up even more.
Both python 2 and python 3 are supported.
.. _jsmin.c by Douglas Crockford:
http://www.crockford.com/javascript/jsmin.c
Original author of Python version: Andr\xe9 Malo
Home page: http://opensource.perlig.de/rjsmin/
Modified by Ross Peoples <ross.peoples@gmail.com> for inclusion into web2py.
"""
__author__ = "Andr\xe9 Malo"
__author__ = getattr(__author__, 'decode', lambda x: __author__)('latin-1')
__docformat__ = "restructuredtext en"
__license__ = "Apache License, Version 2.0"
__version__ = '1.0.2'
__all__ = ['jsmin', 'jsmin_for_posers']
import re as _re
def _make_jsmin(extended=True, python_only=True):
"""
Generate JS minifier based on `jsmin.c by Douglas Crockford`_
.. _jsmin.c by Douglas Crockford:
http://www.crockford.com/javascript/jsmin.c
:Parameters:
`extended` : ``bool``
Extended Regexps? (using lookahead and lookbehind). This is faster,
because it can be optimized way more. The regexps used with `extended`
being false are only left here to allow easier porting to platforms
without extended regex features (and for my own reference...)
`python_only` : ``bool``
Use only the python variant. If true, the c extension is not even
tried to be loaded.
:Return: Minifier
:Rtype: ``callable``
"""
# pylint: disable = R0912, R0914, W0612
if not python_only:
try:
import _rjsmin
except ImportError:
pass
else:
return _rjsmin.jsmin
try:
xrange
except NameError:
xrange = range # pylint: disable = W0622
space_chars = r'[\000-\011\013\014\016-\040]'
line_comment = r'(?://[^\r\n]*)'
space_comment = r'(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)'
string1 = \
r'(?:\047[^\047\\\r\n]*(?:\\(?:[^\r\n]|\r?\n|\r)[^\047\\\r\n]*)*\047)'
string2 = r'(?:"[^"\\\r\n]*(?:\\(?:[^\r\n]|\r?\n|\r)[^"\\\r\n]*)*")'
strings = r'(?:%s|%s)' % (string1, string2)
charclass = r'(?:\[[^\\\]\r\n]*(?:\\[^\r\n][^\\\]\r\n]*)*\])'
nospecial = r'[^/\\\[\r\n]'
if extended:
regex = r'(?:/(?![\r\n/*])%s*(?:(?:\\[^\r\n]|%s)%s*)*/)' % (
nospecial, charclass, nospecial
)
else:
regex = (
r'(?:/(?:[^*/\\\r\n\[]|%s|\\[^\r\n])%s*(?:(?:\\[^\r\n]|%s)%s*)*/)'
)
regex = regex % (charclass, nospecial, charclass, nospecial)
space = r'(?:%s|%s)' % (space_chars, space_comment)
newline = r'(?:%s?[\r\n])' % line_comment
def fix_charclass(result):
""" Fixup string of chars to fit into a regex char class """
pos = result.find('-')
if pos >= 0:
result = r'%s%s-' % (result[:pos], result[pos + 1:])
def sequentize(string):
"""
Notate consecutive characters as sequence
(1-4 instead of 1234)
"""
first, last, result = None, None, []
for char in map(ord, string):
if last is None:
first = last = char
elif last + 1 == char:
last = char
else:
result.append((first, last))
first = last = char
if last is not None:
result.append((first, last))
return ''.join(['%s%s%s' % (
chr(first),
last > first + 1 and '-' or '',
last != first and chr(last) or ''
) for first, last in result])
return _re.sub(r'([\000-\040\047])', # for better portability
lambda m: '\\%03o' % ord(m.group(1)), (sequentize(result)
.replace('\\', '\\\\')
.replace('[', '\\[')
.replace(']', '\\]')
)
)
def id_literal_(what):
""" Make id_literal like char class """
match = _re.compile(what).match
result = ''.join([
chr(c) for c in xrange(127) if not match(chr(c))
])
return '[^%s]' % fix_charclass(result)
def not_id_literal_(keep):
""" Make negated id_literal like char class """
match = _re.compile(id_literal_(keep)).match
result = ''.join([
chr(c) for c in xrange(127) if not match(chr(c))
])
return r'[%s]' % fix_charclass(result)
not_id_literal = not_id_literal_(r'[a-zA-Z0-9_$]')
preregex1 = r'[(,=:\[!&|?{};\r\n]'
preregex2 = r'%(not_id_literal)sreturn' % locals()
if extended:
id_literal = id_literal_(r'[a-zA-Z0-9_$]')
id_literal_open = id_literal_(r'[a-zA-Z0-9_${\[(+-]')
id_literal_close = id_literal_(r'[a-zA-Z0-9_$}\])"\047+-]')
space_sub = _re.compile((
r'([^\047"/\000-\040]+)'
r'|(%(strings)s[^\047"/\000-\040]*)'
r'|(?:(?<=%(preregex1)s)%(space)s*(%(regex)s[^\047"/\000-\040]*))'
r'|(?:(?<=%(preregex2)s)%(space)s*(%(regex)s[^\047"/\000-\040]*))'
r'|(?<=%(id_literal_close)s)'
r'%(space)s*(?:(%(newline)s)%(space)s*)+'
r'(?=%(id_literal_open)s)'
r'|(?<=%(id_literal)s)(%(space)s)+(?=%(id_literal)s)'
r'|%(space)s+'
r'|(?:%(newline)s%(space)s*)+'
) % locals()).sub
def space_subber(match):
""" Substitution callback """
# pylint: disable = C0321, R0911
groups = match.groups()
if groups[0]:
return groups[0]
elif groups[1]:
return groups[1]
elif groups[2]:
return groups[2]
elif groups[3]:
return groups[3]
elif groups[4]:
return '\n'
elif groups[5]:
return ' '
else:
return ''
def jsmin(script): # pylint: disable = W0621
r"""
Minify javascript based on `jsmin.c by Douglas Crockford`_\.
Instead of parsing the stream char by char, it uses a regular
expression approach which minifies the whole script with one big
substitution regex.
.. _jsmin.c by Douglas Crockford:
http://www.crockford.com/javascript/jsmin.c
:Parameters:
`script` : ``str``
Script to minify
:Return: Minified script
:Rtype: ``str``
"""
return space_sub(space_subber, '\n%s\n' % script).strip()
else:
pre_regex = r'(?:%(preregex1)s|%(preregex2)s)' % locals()
not_id_literal_open = not_id_literal_(r'[a-zA-Z0-9_${\[(+-]')
not_id_literal_close = not_id_literal_(r'[a-zA-Z0-9_$}\])"\047+-]')
space_norm_sub = _re.compile((
r'(%(strings)s)'
r'|(?:(%(pre_regex)s)%(space)s*(%(regex)s))'
r'|(%(space)s)+'
r'|(?:(%(newline)s)%(space)s*)+'
) % locals()).sub
def space_norm_subber(match):
""" Substitution callback """
# pylint: disable = C0321
groups = match.groups()
if groups[0]:
return groups[0]
elif groups[1]:
return groups[1].replace('\r', '\n') + groups[2]
elif groups[3]:
return ' '
elif groups[4]:
return '\n'
space_sub1 = _re.compile((
r'[\040\n]?(%(strings)s|%(pre_regex)s%(regex)s)'
r'|\040(%(not_id_literal)s)'
r'|\n(%(not_id_literal_open)s)'
) % locals()).sub
def space_subber1(match):
""" Substitution callback """
groups = match.groups()
return groups[0] or groups[1] or groups[2]
space_sub2 = _re.compile((
r'(%(strings)s)\040?'
r'|(%(pre_regex)s%(regex)s)[\040\n]?'
r'|(%(not_id_literal)s)\040'
r'|(%(not_id_literal_close)s)\n'
) % locals()).sub
def space_subber2(match):
""" Substitution callback """
groups = match.groups()
return groups[0] or groups[1] or groups[2] or groups[3]
def jsmin(script):
r"""
Minify javascript based on `jsmin.c by Douglas Crockford`_\.
Instead of parsing the stream char by char, it uses a regular
expression approach. The script is minified with three passes:
normalization
Control character are mapped to spaces, spaces and newlines
are squeezed and comments are stripped.
space removal 1
Spaces before certain tokens are removed
space removal 2
Spaces after certain tokens are remove
.. _jsmin.c by Douglas Crockford:
http://www.crockford.com/javascript/jsmin.c
:Parameters:
`script` : ``str``
Script to minify
:Return: Minified script
:Rtype: ``str``
"""
return space_sub2(space_subber2,
space_sub1(space_subber1,
space_norm_sub(space_norm_subber,
'\n%s\n' % script)
)
).strip()
return jsmin
jsmin = _make_jsmin()
#####################
# EXAMPLE USAGE #
#####################
#
# import jsmin
# jsmin.jsmin(script)
#
def jsmin_for_posers(script):
r"""
Minify javascript based on `jsmin.c by Douglas Crockford`_\.
Instead of parsing the stream char by char, it uses a regular
expression approach which minifies the whole script with one big
substitution regex.
.. _jsmin.c by Douglas Crockford:
http://www.crockford.com/javascript/jsmin.c
:Warning: This function is the digest of a _make_jsmin() call. It just
utilizes the resulting regex. It's just for fun here and may
vanish any time. Use the `jsmin` function instead.
:Parameters:
`script` : ``str``
Script to minify
:Return: Minified script
:Rtype: ``str``
"""
def subber(match):
""" Substitution callback """
groups = match.groups()
return (
groups[0] or
groups[1] or
groups[2] or
groups[3] or
(groups[4] and '\n') or
(groups[5] and ' ') or
''
)
return _re.sub(
r'([^\047"/\000-\040]+)|((?:(?:\047[^\047\\\r\n]*(?:\\(?:[^\r\n]|\r?'
r'\n|\r)[^\047\\\r\n]*)*\047)|(?:"[^"\\\r\n]*(?:\\(?:[^\r\n]|\r?\n|'
r'\r)[^"\\\r\n]*)*"))[^\047"/\000-\040]*)|(?:(?<=[(,=:\[!&|?{};\r\n]'
r')(?:[\000-\011\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/'
r'))*((?:/(?![\r\n/*])[^/\\\[\r\n]*(?:(?:\\[^\r\n]|(?:\[[^\\\]\r\n]*'
r'(?:\\[^\r\n][^\\\]\r\n]*)*\]))[^/\\\[\r\n]*)*/)[^\047"/\000-\040]*'
r'))|(?:(?<=[\000-#%-,./:-@\[-^`{-~-]return)(?:[\000-\011\013\014\01'
r'6-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/))*((?:/(?![\r\n/*])[^/'
r'\\\[\r\n]*(?:(?:\\[^\r\n]|(?:\[[^\\\]\r\n]*(?:\\[^\r\n][^\\\]\r\n]'
r'*)*\]))[^/\\\[\r\n]*)*/)[^\047"/\000-\040]*))|(?<=[^\000-!#%&(*,./'
r':-@\[\\^`{|~])(?:[\000-\011\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/'
r'*][^*]*\*+)*/))*(?:((?:(?://[^\r\n]*)?[\r\n]))(?:[\000-\011\013\01'
r'4\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/))*)+(?=[^\000-#%-\04'
r'7)*,./:-@\\-^`|-~])|(?<=[^\000-#%-,./:-@\[-^`{-~-])((?:[\000-\011'
r'\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/)))+(?=[^\000-'
r'#%-,./:-@\[-^`{-~-])|(?:[\000-\011\013\014\016-\040]|(?:/\*[^*]*\*'
r'+(?:[^/*][^*]*\*+)*/))+|(?:(?:(?://[^\r\n]*)?[\r\n])(?:[\000-\011'
r'\013\014\016-\040]|(?:/\*[^*]*\*+(?:[^/*][^*]*\*+)*/))*)+',
subber, '\n%s\n' % script
).strip()
if __name__ == '__main__':
import sys as _sys
_sys.stdout.write(jsmin(_sys.stdin.read()))