Varia's website
https://varia.zone
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.
308 lines
11 KiB
308 lines
11 KiB
1 week ago
|
"""
|
||
|
CodeHilite Extension for Python-Markdown
|
||
|
========================================
|
||
|
|
||
|
Adds code/syntax highlighting to standard Python-Markdown code blocks.
|
||
|
|
||
|
See <https://Python-Markdown.github.io/extensions/code_hilite>
|
||
|
for documentation.
|
||
|
|
||
|
Original code Copyright 2006-2008 [Waylan Limberg](http://achinghead.com/).
|
||
|
|
||
|
All changes Copyright 2008-2014 The Python Markdown Project
|
||
|
|
||
|
License: [BSD](https://opensource.org/licenses/bsd-license.php)
|
||
|
|
||
|
"""
|
||
|
|
||
|
from . import Extension
|
||
|
from ..treeprocessors import Treeprocessor
|
||
|
from ..util import parseBoolValue
|
||
|
|
||
|
try: # pragma: no cover
|
||
|
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: # pragma: no cover
|
||
|
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: # pragma: no cover
|
||
|
return []
|
||
|
|
||
|
|
||
|
# ------------------ The Main CodeHilite Class ----------------------
|
||
|
class CodeHilite:
|
||
|
"""
|
||
|
Determine language of source code, and pass it on to the Pygments highlighter.
|
||
|
|
||
|
Usage:
|
||
|
code = CodeHilite(src=some_code, lang='python')
|
||
|
html = code.hilite()
|
||
|
|
||
|
Arguments:
|
||
|
* src: Source string or any object with a .readline attribute.
|
||
|
|
||
|
* lang: String name of Pygments lexer to use for highlighting. Default: `None`.
|
||
|
|
||
|
* guess_lang: Auto-detect which lexer to use. Ignored if `lang` is set to a valid
|
||
|
value. Default: `True`.
|
||
|
|
||
|
* use_pygments: Pass code to pygments for code highlighting. If `False`, the code is
|
||
|
instead wrapped for highlighting by a JavaScript library. Default: `True`.
|
||
|
|
||
|
* linenums: An alias to Pygments `linenos` formatter option. Default: `None`.
|
||
|
|
||
|
* css_class: An alias to Pygments `cssclass` formatter option. Default: 'codehilite'.
|
||
|
|
||
|
* lang_prefix: Prefix prepended to the language when `use_pygments` is `False`.
|
||
|
Default: "language-".
|
||
|
|
||
|
Other Options:
|
||
|
Any other options are accepted and passed on to the lexer and formatter. Therefore,
|
||
|
valid options include any options which are accepted by the `html` formatter or
|
||
|
whichever lexer the code's language uses. Note that most lexers do not have any
|
||
|
options. However, a few have very useful options, such as PHP's `startinline` option.
|
||
|
Any invalid options are ignored without error.
|
||
|
|
||
|
Formatter options: https://pygments.org/docs/formatters/#HtmlFormatter
|
||
|
Lexer Options: https://pygments.org/docs/lexers/
|
||
|
|
||
|
Advanced Usage:
|
||
|
code = CodeHilite(
|
||
|
src = some_code,
|
||
|
lang = 'php',
|
||
|
startinline = True, # Lexer option. Snippet does not start with `<?php`.
|
||
|
linenostart = 42, # Formatter option. Snippet starts on line 42.
|
||
|
hl_lines = [45, 49, 50], # Formatter option. Highlight lines 45, 49, and 50.
|
||
|
linenos = 'inline' # Formatter option. Avoid alignment problems.
|
||
|
)
|
||
|
html = code.hilite()
|
||
|
|
||
|
"""
|
||
|
|
||
|
def __init__(self, src, **options):
|
||
|
self.src = src
|
||
|
self.lang = options.pop('lang', None)
|
||
|
self.guess_lang = options.pop('guess_lang', True)
|
||
|
self.use_pygments = options.pop('use_pygments', True)
|
||
|
self.lang_prefix = options.pop('lang_prefix', 'language-')
|
||
|
|
||
|
if 'linenos' not in options:
|
||
|
options['linenos'] = options.pop('linenums', None)
|
||
|
if 'cssclass' not in options:
|
||
|
options['cssclass'] = options.pop('css_class', 'codehilite')
|
||
|
if 'wrapcode' not in options:
|
||
|
# Override pygments default
|
||
|
options['wrapcode'] = True
|
||
|
# Disallow use of `full` option
|
||
|
options['full'] = False
|
||
|
|
||
|
self.options = options
|
||
|
|
||
|
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, **self.options)
|
||
|
except ValueError:
|
||
|
try:
|
||
|
if self.guess_lang:
|
||
|
lexer = guess_lexer(self.src, **self.options)
|
||
|
else:
|
||
|
lexer = get_lexer_by_name('text', **self.options)
|
||
|
except ValueError: # pragma: no cover
|
||
|
lexer = get_lexer_by_name('text', **self.options)
|
||
|
formatter = get_formatter_by_name('html', **self.options)
|
||
|
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('{}{}'.format(self.lang_prefix, self.lang))
|
||
|
if self.options['linenos']:
|
||
|
classes.append('linenums')
|
||
|
class_str = ''
|
||
|
if classes:
|
||
|
class_str = ' class="{}"'.format(' '.join(classes))
|
||
|
return '<pre class="{}"><code{}>{}\n</code></pre>\n'.format(
|
||
|
self.options['cssclass'],
|
||
|
class_str,
|
||
|
txt
|
||
|
)
|
||
|
|
||
|
def _parseHeader(self):
|
||
|
"""
|
||
|
Determines language of a code block from shebang line and whether the
|
||
|
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 identification 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: # pragma: no cover
|
||
|
self.lang = None
|
||
|
if m.group('path'):
|
||
|
# path exists - restore first line
|
||
|
lines.insert(0, fl)
|
||
|
if self.options['linenos'] is None and m.group('shebang'):
|
||
|
# Overridable and Shebang exists - use line numbers
|
||
|
self.options['linenos'] = True
|
||
|
|
||
|
self.options['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 code_unescape(self, text):
|
||
|
"""Unescape code."""
|
||
|
text = text.replace("<", "<")
|
||
|
text = text.replace(">", ">")
|
||
|
# Escaped '&' should be replaced at the end to avoid
|
||
|
# conflicting with < and >.
|
||
|
text = text.replace("&", "&")
|
||
|
return text
|
||
|
|
||
|
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(
|
||
|
self.code_unescape(block[0].text),
|
||
|
tab_length=self.md.tab_length,
|
||
|
style=self.config.pop('pygments_style', 'default'),
|
||
|
**self.config
|
||
|
)
|
||
|
placeholder = self.md.htmlStash.store(code.hilite())
|
||
|
# 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, **kwargs):
|
||
|
# define default configs
|
||
|
self.config = {
|
||
|
'linenums': [None,
|
||
|
"Use lines numbers. True|table|inline=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'],
|
||
|
'lang_prefix': [
|
||
|
'language-',
|
||
|
'Prefix prepended to the language when use_pygments is false. Default: "language-"'
|
||
|
]
|
||
|
}
|
||
|
|
||
|
for key, value in kwargs.items():
|
||
|
if key in self.config:
|
||
|
self.setConfig(key, value)
|
||
|
else:
|
||
|
# manually set unknown keywords.
|
||
|
if isinstance(value, str):
|
||
|
try:
|
||
|
# Attempt to parse str as a bool value
|
||
|
value = parseBoolValue(value, preserve_none=True)
|
||
|
except ValueError:
|
||
|
pass # Assume it's not a bool value. Use as-is.
|
||
|
self.config[key] = [value, '']
|
||
|
|
||
|
def extendMarkdown(self, md):
|
||
|
""" Add HilitePostprocessor to Markdown instance. """
|
||
|
hiliter = HiliteTreeprocessor(md)
|
||
|
hiliter.config = self.getConfigs()
|
||
|
md.treeprocessors.register(hiliter, 'hilite', 30)
|
||
|
|
||
|
md.registerExtension(self)
|
||
|
|
||
|
|
||
|
def makeExtension(**kwargs): # pragma: no cover
|
||
|
return CodeHiliteExtension(**kwargs)
|