1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
|
"""
CodeHilite Extension for Python-Markdown
========================================
Adds code/syntax highlighting to standard Python-Markdown code blocks.
See <https://pythonhosted.org/Markdown/extensions/code_hilite.html>
for documentation.
Original code Copyright 2006-2008 [Waylan Limberg](http://achinghead.com/).
All changes Copyright 2008-2014 The Python Markdown Project
License: [BSD](http://www.opensource.org/licenses/bsd-license.php)
"""
from __future__ import absolute_import
from __future__ import unicode_literals
from . import Extension
from ..treeprocessors import Treeprocessor
try:
from pygments import highlight
from pygments.lexers import get_lexer_by_name, guess_lexer
from pygments.formatters import get_formatter_by_name
pygments = True
except ImportError:
pygments = False
def parse_hl_lines(expr):
"""Support our syntax for emphasizing certain lines of code.
expr should be like '1 2' to emphasize lines 1 and 2 of a code block.
Returns a list of ints, the line numbers to emphasize.
"""
if not expr:
return []
try:
return list(map(int, expr.split()))
except ValueError:
return []
# ------------------ The Main CodeHilite Class ----------------------
class CodeHilite(object):
"""
Determine language of source code, and pass it into pygments hilighter.
Basic Usage:
>>> code = CodeHilite(src = 'some text')
>>> html = code.hilite()
* src: Source string or any object with a .readline attribute.
* linenums: (Boolean) Set line numbering to 'on' (True),
'off' (False) or 'auto'(None). Set to 'auto' by default.
* guess_lang: (Boolean) Turn language auto-detection
'on' or 'off' (on by default).
* css_class: Set class name of wrapper div ('codehilite' by default).
* hl_lines: (List of integers) Lines to emphasize, 1-indexed.
Low Level Usage:
>>> code = CodeHilite()
>>> code.src = 'some text' # String or anything with a .readline attr.
>>> code.linenos = True # Turns line numbering on or of.
>>> html = code.hilite()
"""
def __init__(self, src=None, linenums=None, guess_lang=True,
css_class="codehilite", lang=None, style='default',
noclasses=False, tab_length=4, hl_lines=None, use_pygments=True):
self.src = src
self.lang = lang
self.linenums = linenums
self.guess_lang = guess_lang
self.css_class = css_class
self.style = style
self.noclasses = noclasses
self.tab_length = tab_length
self.hl_lines = hl_lines or []
self.use_pygments = use_pygments
def hilite(self):
"""
Pass code to the [Pygments](http://pygments.pocoo.org/) highliter with
optional line numbers. The output should then be styled with css to
your liking. No styles are applied by default - only styling hooks
(i.e.: <span class="k">).
returns : A string of html.
"""
self.src = self.src.strip('\n')
if self.lang is None:
self._parseHeader()
if pygments and self.use_pygments:
try:
lexer = get_lexer_by_name(self.lang)
except ValueError:
try:
if self.guess_lang:
lexer = guess_lexer(self.src)
else:
lexer = get_lexer_by_name('text')
except ValueError:
lexer = get_lexer_by_name('text')
formatter = get_formatter_by_name('html',
linenos=self.linenums,
cssclass=self.css_class,
style=self.style,
noclasses=self.noclasses,
hl_lines=self.hl_lines)
return highlight(self.src, lexer, formatter)
else:
# just escape and build markup usable by JS highlighting libs
txt = self.src.replace('&', '&')
txt = txt.replace('<', '<')
txt = txt.replace('>', '>')
txt = txt.replace('"', '"')
classes = []
if self.lang:
classes.append('language-%s' % self.lang)
if self.linenums:
classes.append('linenums')
class_str = ''
if classes:
class_str = ' class="%s"' % ' '.join(classes)
return '<pre class="%s"><code%s>%s</code></pre>\n' % \
(self.css_class, class_str, txt)
def _parseHeader(self):
"""
Determines language of a code block from shebang line and whether said
line should be removed or left in place. If the sheband line contains a
path (even a single /) then it is assumed to be a real shebang line and
left alone. However, if no path is given (e.i.: #!python or :::python)
then it is assumed to be a mock shebang for language identifitation of
a code fragment and removed from the code block prior to processing for
code highlighting. When a mock shebang (e.i: #!python) is found, line
numbering is turned on. When colons are found in place of a shebang
(e.i.: :::python), line numbering is left in the current state - off
by default.
Also parses optional list of highlight lines, like:
:::python hl_lines="1 3"
"""
import re
# split text into lines
lines = self.src.split("\n")
# pull first line to examine
fl = lines.pop(0)
c = re.compile(r'''
(?:(?:^::+)|(?P<shebang>^[#]!)) # Shebang or 2 or more colons
(?P<path>(?:/\w+)*[/ ])? # Zero or 1 path
(?P<lang>[\w#.+-]*) # The language
\s* # Arbitrary whitespace
# Optional highlight lines, single- or double-quote-delimited
(hl_lines=(?P<quot>"|')(?P<hl_lines>.*?)(?P=quot))?
''', re.VERBOSE)
# search first line for shebang
m = c.search(fl)
if m:
# we have a match
try:
self.lang = m.group('lang').lower()
except IndexError:
self.lang = None
if m.group('path'):
# path exists - restore first line
lines.insert(0, fl)
if self.linenums is None and m.group('shebang'):
# Overridable and Shebang exists - use line numbers
self.linenums = True
self.hl_lines = parse_hl_lines(m.group('hl_lines'))
else:
# No match
lines.insert(0, fl)
self.src = "\n".join(lines).strip("\n")
# ------------------ The Markdown Extension -------------------------------
class HiliteTreeprocessor(Treeprocessor):
""" Hilight source code in code blocks. """
def run(self, root):
""" Find code blocks and store in htmlStash. """
blocks = root.iter('pre')
for block in blocks:
if len(block) == 1 and block[0].tag == 'code':
code = CodeHilite(
block[0].text,
linenums=self.config['linenums'],
guess_lang=self.config['guess_lang'],
css_class=self.config['css_class'],
style=self.config['pygments_style'],
noclasses=self.config['noclasses'],
tab_length=self.markdown.tab_length,
use_pygments=self.config['use_pygments']
)
placeholder = self.markdown.htmlStash.store(code.hilite(),
safe=True)
# Clear codeblock in etree instance
block.clear()
# Change to p element which will later
# be removed when inserting raw html
block.tag = 'p'
block.text = placeholder
class CodeHiliteExtension(Extension):
""" Add source code hilighting to markdown codeblocks. """
def __init__(self, *args, **kwargs):
# define default configs
self.config = {
'linenums': [None,
"Use lines numbers. True=yes, False=no, None=auto"],
'guess_lang': [True,
"Automatic language detection - Default: True"],
'css_class': ["codehilite",
"Set class name for wrapper <div> - "
"Default: codehilite"],
'pygments_style': ['default',
'Pygments HTML Formatter Style '
'(Colorscheme) - Default: default'],
'noclasses': [False,
'Use inline styles instead of CSS classes - '
'Default false'],
'use_pygments': [True,
'Use Pygments to Highlight code blocks. '
'Disable if using a JavaScript library. '
'Default: True']
}
super(CodeHiliteExtension, self).__init__(*args, **kwargs)
def extendMarkdown(self, md, md_globals):
""" Add HilitePostprocessor to Markdown instance. """
hiliter = HiliteTreeprocessor(md)
hiliter.config = self.getConfigs()
md.treeprocessors.add("hilite", hiliter, "<inline")
md.registerExtension(self)
def makeExtension(*args, **kwargs):
return CodeHiliteExtension(*args, **kwargs)
|
