1 files changed, 54 insertions, 0 deletions
diff --git a/markdown/extensions/sane_lists.py b/markdown/extensions/sane_lists.py
new file mode 100644
index 0000000..e27eb18
--- /dev/null
+++ b/markdown/extensions/sane_lists.py
@@ -0,0 +1,54 @@
+"""
+Sane List Extension for Python-Markdown
+=======================================
+
+Modify the behavior of Lists in Python-Markdown to act in a sane manor.
+
+See <https://Python-Markdown.github.io/extensions/sane_lists>
+for documentation.
+
+Original code Copyright 2011 [Waylan Limberg](http://achinghead.com)
+
+All changes Copyright 2011-2014 The Python Markdown Project
+
+License: [BSD](https://opensource.org/licenses/bsd-license.php)
+
+"""
+
+from . import Extension
+from ..blockprocessors import OListProcessor, UListProcessor
+import re
+
+
+class SaneOListProcessor(OListProcessor):
+
+    SIBLING_TAGS = ['ol']
+    LAZY_OL = False
+
+    def __init__(self, parser):
+        super().__init__(parser)
+        self.CHILD_RE = re.compile(r'^[ ]{0,%d}((\d+\.))[ ]+(.*)' %
+                                   (self.tab_length - 1))
+
+
+class SaneUListProcessor(UListProcessor):
+
+    SIBLING_TAGS = ['ul']
+
+    def __init__(self, parser):
+        super().__init__(parser)
+        self.CHILD_RE = re.compile(r'^[ ]{0,%d}(([*+-]))[ ]+(.*)' %
+                                   (self.tab_length - 1))
+
+
+class SaneListExtension(Extension):
+    """ Add sane lists to Markdown. """
+
+    def extendMarkdown(self, md):
+        """ Override existing Processors. """
+        md.parser.blockprocessors.register(SaneOListProcessor(md.parser), 'olist', 40)
+        md.parser.blockprocessors.register(SaneUListProcessor(md.parser), 'ulist', 30)
+
+
+def makeExtension(**kwargs):  # pragma: no cover
+    return SaneListExtension(**kwargs)