Added a 'use_pygments' config option to CodeHilite.

Fixes #386. I'm doing this against my better judgement. The only reason is
that I'm using the HTML format suggested by the HTML5 Spec and will simply
not consider any alternate output. If a JavaScript library requires something
else, to bad. I don't care. That library should support the format
suggested by the spec or I'm not interested in it. If you want something else
then you can create your own extension which does whatever you want.

Author: waylan

docs/extensions/code_hilite.txt

@@ -31,7 +31,7 @@ language. When that fails, the code block will display as un-highlighted code.
 [documentation]: http://pygments.org/docs
 
 !!! Note
-    The css and/or javascript is not included as part of this extension
+    The css and/or JavaScript is not included as part of this extension
     but must be provided by the end user. The Pygments project provides
     default css styles which you may find to be a useful starting point.
 
@@ -165,3 +165,12 @@ The following options are provided to configure the output:
 
 * **`noclasses`**:
     Use inline styles instead of CSS classes. Defaults to `False`.
+
+* **`use_pygments`**:
+    Defaults to `True`. Set to `False` to disable the use of Pygments.
+    If a language is defined for a code block, it will be assigned to the
+    `<code>` tag as a class in the manner suggested by the [HTML5 spec][spec]
+    (alternate output will not be entertained) and might be used by a JavaScript
+    library in the browser to highlight the code block.
+
+[spec]: http://www.w3.org/TR/html5/text-level-semantics.html#the-code-element

docs/release-2.6.txt

@@ -202,6 +202,18 @@ worked on PyPy for some time, it is now officially supported and tested on PyPy.
 
 [TOC]: extensions/toc.html
 
+*   The [CodeHilite][ch] Extension has gained a new config option: `use_pygments`.
+    The option is `True` by default, however, it allows one to turn off Pygments code
+    highlighting (set to `False`) while preserving the language detection features of
+    the extension. Note that Pygments language detection is not used as that would 'use
+    Pygments`. If a language is defined for a code block, it will be assigned to the
+    `<code>` tag as a class in the manner suggested by the [HTML5 spec][spec]
+    (alternate output will not be entertained) and might be used by a JavaScript
+    library in the browser to highlight the code block.
+
+[ch]: extensions/code_hilite.html
+[spec]: http://www.w3.org/TR/html5/text-level-semantics.html#the-code-element
+
 *   Test coverage has been improved including running [flake8]. While those changes
     will not directly effect end users, the code is being better tested which will 
     benefit everyone.

markdown/extensions/codehilite.py

@@ -75,7 +75,7 @@ class CodeHilite(object):
 
     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):
+                 noclasses=False, tab_length=4, hl_lines=None, use_pygments=True):
         self.src = src
         self.lang = lang
         self.linenums = linenums
@@ -85,6 +85,7 @@ def __init__(self, src=None, linenums=None, guess_lang=True,
         self.noclasses = noclasses
         self.tab_length = tab_length
         self.hl_lines = hl_lines or []
+        self.use_pygments = use_pygments
 
     def hilite(self):
         """
@@ -102,7 +103,7 @@ def hilite(self):
         if self.lang is None:
             self._parseHeader()
 
-        if pygments:
+        if pygments and self.use_pygments:
             try:
                 lexer = get_lexer_by_name(self.lang)
             except ValueError:
@@ -211,7 +212,8 @@ def run(self, root):
                     css_class=self.config['css_class'],
                     style=self.config['pygments_style'],
                     noclasses=self.config['noclasses'],
-                    tab_length=self.markdown.tab_length
+                    tab_length=self.markdown.tab_length,
+                    use_pygments=self.config['use_pygments']
                 )
                 placeholder = self.markdown.htmlStash.store(code.hilite(),
                                                             safe=True)
@@ -231,9 +233,6 @@ def __init__(self, *args, **kwargs):
         self.config = {
             'linenums': [None,
                          "Use lines numbers. True=yes, False=no, None=auto"],
-            'force_linenos': [False,
-                              "Depreciated! Use 'linenums' instead. Force "
-                              "line numbers - Default: False"],
             'guess_lang': [True,
                            "Automatic language detection - Default: True"],
             'css_class': ["codehilite",
@@ -244,7 +243,11 @@ def __init__(self, *args, **kwargs):
                                '(Colorscheme) - Default: default'],
             'noclasses': [False,
                           'Use inline styles instead of CSS classes - '
-                          'Default false']
+                          '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)

tests/test_extensions.py

@@ -226,6 +226,17 @@ def testHighlightLinesWithColon(self):
                     '#line 3</code></pre>'
                 )
 
+    def testUsePygmentsFalse(self):
+        text = '\t:::Python\n\t# A Code Comment'
+        md = markdown.Markdown(
+            extensions=[markdown.extensions.codehilite.CodeHiliteExtension(use_pygments=False)]
+        )
+        self.assertEqual(
+            md.convert(text),
+            '<pre class="codehilite"><code class="language-python"># A Code Comment'
+            '</code></pre>'
+        )
+
 
 class TestFencedCode(unittest.TestCase):
     """ Test fenced_code extension. """