10 files changed, 94 insertions(+), 16 deletions(-)

M src/wiki/core/markdown/__init__.py
M src/wiki/core/markdown/mdx/codehilite.py
M src/wiki/core/markdown/mdx/previewlinks.py
M src/wiki/core/markdown/mdx/responsivetable.py
M src/wiki/plugins/attachments/markdown_extensions.py
M src/wiki/plugins/editsection/markdown_extensions.py
M src/wiki/plugins/images/markdown_extensions.py
M src/wiki/plugins/macros/mdx/macro.py
M src/wiki/plugins/macros/mdx/wikilinks.py
M src/wiki/plugins/redlinks/mdx/redlinks.py

@@ 23,8 23,8 @@ class ArticleMarkdown(markdown.Markdown):
 
     def get_markdown_extensions(self):
         extensions = list(settings.MARKDOWN_KWARGS.get("extensions", []))
-        extensions += self.core_extensions()
-        extensions += plugin_registry.get_markdown_extensions()
+        extensions = self.core_extensions()
+        extensions = plugin_registry.get_markdown_extensions()
         return extensions
 
     def convert(self, text, *args, **kwargs):


@@ 51,3 51,59 @@ class ArticleMarkdown(markdown.Markdown):
 def article_markdown(text, article, *args, **kwargs):
     md = ArticleMarkdown(article, *args, **kwargs)
     return md.convert(text)
+
+
+def add_to_registry(processor, key, value, location):
+    """Utility function to register a key by location to Markdown's registry.
+
+    Parameters:
+    * `processor`: Markdown Registry instance
+    * `key`: A string used to reference the item.
+    * `value`: The item being registered.
+    * `location`: Where to register the new key
+
+    location can be one of the strings below:
+    * _begin (registers the key as the highest priority)
+    * _end (registers the key as the lowest priority)
+    * a string that starts with `<` or `>` (sets priority halfway between existing priorities)
+
+    Returns: None
+    Raises: ValueError if location is an invalid string.
+    """
+
+    if len(processor) == 0:
+        # This is the first item. Set priority to 50.
+        priority = 50
+    elif location == "_begin":
+        processor._sort()
+        # Set priority 5 greater than highest existing priority
+        priority = processor._priority[0].priority +  5
+    elif location == "_end":
+        processor._sort()
+        # Set priority 5 less than lowest existing priority
+        priority = processor._priority[-1].priority - 5
+    elif location.startswith("<") or location.startswith(">"):
+        # Set priority halfway between existing priorities.
+        i = processor.get_index_for_name(location[1:])
+        if location.startswith("<"):
+            after = processor._priority[i].priority
+            if i > 0:
+                before = processor._priority[i - 1].priority
+            else:
+                # Location is first item`
+                before = after + 10
+        else:
+            # location.startswith('>')
+            before = processor._priority[i].priority
+            if i < len(processor) - 1:
+                after = processor._priority[i + 1].priority
+            else:
+                # location is last item
+                after = before - 10
+        priority = before - ((before - after) / 2)
+    else:
+        raise ValueError(
+            'Not a valid location: "%s". Location key '
+            'must start with a ">" or "<".' % location
+        )
+    processor.register(value, key, priority)

@@ 5,6 5,7 @@ from markdown.extensions.codehilite import CodeHilite
 from markdown.extensions.codehilite import CodeHiliteExtension
 from markdown.preprocessors import Preprocessor
 from markdown.treeprocessors import Treeprocessor
+from wiki.core.markdown import add_to_registry
 
 logger = logging.getLogger(__name__)
 


@@ 107,7 108,7 @@ class WikiCodeHiliteExtension(CodeHiliteExtension):
                 "'codehilite' from WIKI_MARKDOWN_KWARGS"
             )
             del md.treeprocessors["hilite"]
-        md.treeprocessors.add("hilite", hiliter, "<inline")
+        add_to_registry(md.treeprocessors, "hilite", hiliter, "<inline")
 
         if "fenced_code_block" in md.preprocessors:
             logger.warning(


@@ 117,7 118,9 @@ class WikiCodeHiliteExtension(CodeHiliteExtension):
             del md.preprocessors["fenced_code_block"]
         hiliter = WikiFencedBlockPreprocessor(md)
         hiliter.config = self.getConfigs()
-        md.preprocessors.add("fenced_code_block", hiliter, ">normalize_whitespace")
+        add_to_registry(
+            md.preprocessors, "fenced_code_block", hiliter, ">normalize_whitespace"
+        )
 
         md.registerExtension(self)
 

@@ 1,5 1,6 @@
 import markdown
 from markdown.treeprocessors import Treeprocessor
+from wiki.core.markdown import add_to_registry
 
 
 class PreviewLinksExtension(markdown.Extension):


@@ 7,7 8,7 @@ class PreviewLinksExtension(markdown.Extension):
     """Markdown Extension that sets all anchor targets to _blank when in preview mode"""
 
     def extendMarkdown(self, md):
-        md.treeprocessors.add("previewlinks", PreviewLinksTree(md), "_end")
+        add_to_registry(md.treeprocessors, "previewlinks", PreviewLinksTree(md), "_end")
 
 
 class PreviewLinksTree(Treeprocessor):

@@ 1,13 1,16 @@
 from xml.etree import ElementTree as etree
 import markdown
 from markdown.treeprocessors import Treeprocessor
+from wiki.core.markdown import add_to_registry
 
 
 class ResponsiveTableExtension(markdown.Extension):
     """Wraps all tables with Bootstrap's table-responsive class"""
 
     def extendMarkdown(self, md):
-        md.treeprocessors.add("responsivetable", ResponsiveTableTree(md), "_end")
+        add_to_registry(
+            md.treeprocessors, "responsivetable", ResponsiveTableTree(md), "_end"
+        )
 
 
 class ResponsiveTableTree(Treeprocessor):

@@ 4,6 4,7 @@ import markdown
 from django.contrib.auth.models import AnonymousUser
 from django.template.loader import render_to_string
 from django.urls import reverse
+from wiki.core.markdown import add_to_registry
 from wiki.core.permissions import can_read
 from wiki.plugins.attachments import models
 


@@ 19,9 20,12 @@ class AttachmentExtension(markdown.Extension):
 
     def extendMarkdown(self, md):
         """ Insert AbbrPreprocessor before ReferencePreprocessor. """
-        md.preprocessors.add(
-            "dw-attachments", AttachmentPreprocessor(md), ">html_block"
-        )
+        add_to_registry(
+            md.preprocessors,
+            "dw-attachments",
+            AttachmentPreprocessor(md),
+            ">html_block",
+         )
 
 
 class AttachmentPreprocessor(markdown.preprocessors.Preprocessor):

@@ 4,6 4,7 @@ from xml.etree import ElementTree as etree
 from django.urls import reverse
 from markdown import Extension
 from markdown.treeprocessors import Treeprocessor
+from wiki.core.markdown import add_to_registry
 
 from . import settings
 


@@ 18,10 19,10 @@ class EditSectionExtension(Extension):
         }
         super().__init__(**kwargs)
 
-    def extendMarkdown(self, md, md_globals):
+    def extendMarkdown(self, md):
         ext = EditSectionProcessor(md)
         ext.config = self.config
-        md.treeprocessors.add("editsection", ext, "_end")
+        add_to_registry(md.treeprocessors, "editsection", ext, "_end")
 
 
 def get_header_id(header):

@@ 4,6 4,7 @@ import markdown
 from django.template.loader import render_to_string
 from wiki.plugins.images import models
 from wiki.plugins.images import settings
+from wiki.core.markdown import add_to_registry
 
 IMAGE_RE = (
     r"(?:"


@@ 32,8 33,12 @@ class ImageExtension(markdown.Extension):
     """Images plugin markdown extension for django-wiki."""
 
     def extendMarkdown(self, md):
-        md.inlinePatterns.add("dw-images", ImagePattern(IMAGE_RE, md), ">link")
-        md.postprocessors.add("dw-images-cleanup", ImagePostprocessor(md), ">raw_html")
+        add_to_registry(
+            md.inlinePatterns, "dw-images", ImagePattern(IMAGE_RE, md), ">link"
+        )
+        add_to_registry(
+            md.postprocessors, "dw-images-cleanup", ImagePostprocessor(md), ">raw_html"
+         )
 
 
 class ImagePattern(markdown.inlinepatterns.Pattern):

@@ 4,6 4,7 @@ import markdown
 from django.template.loader import render_to_string
 from django.utils.translation import gettext as _
 from wiki.plugins.macros import settings
+from wiki.core.markdown import add_to_registry
 
 # See:
 # http://stackoverflow.com/questions/430759/regex-for-managing-escaped-characters-for-items-like-string-literals


@@ 20,7 21,9 @@ class MacroExtension(markdown.Extension):
     """Macro plugin markdown extension for django-wiki."""
 
     def extendMarkdown(self, md):
-        md.inlinePatterns.add("dw-macros", MacroPattern(MACRO_RE, md), ">link")
+        add_to_registry(
+            md.inlinePatterns, "dw-macros", MacroPattern(MACRO_RE, md), ">link"
+        )
 
 
 class MacroPattern(markdown.inlinepatterns.Pattern):

@@ 8,6 8,7 @@ import markdown
 from django.urls import reverse
 from markdown.extensions import Extension
 from markdown.extensions import wikilinks
+from wiki.core.markdown import add_to_registry
 
 
 def build_url(label, base, end, md):


@@ 42,7 43,7 @@ class WikiLinkExtension(Extension):
         WIKILINK_RE = r"\[\[([\w0-9_ -]+)\]\]"
         wikilinkPattern = WikiLinks(WIKILINK_RE, self.getConfigs())
         wikilinkPattern.md = md
-        md.inlinePatterns.add("wikilink", wikilinkPattern, "<not_strong")
+        add_to_registry(md.inlinePatterns, "wikilink", wikilinkPattern, "<not_strong")
 
 
 class WikiLinks(wikilinks.WikiLinksInlineProcessor):

@@ 6,6 6,7 @@ from markdown.extensions import Extension
 from markdown.postprocessors import AndSubstitutePostprocessor
 from markdown.treeprocessors import Treeprocessor
 from wiki.models import URLPath
+from wiki.core.markdown import add_to_registry
 
 
 def urljoin_internal(base, url):


@@ 107,7 108,7 @@ class LinkExtension(Extension):
         md.registerExtension(self)
         self.md = md
         ext = self.TreeProcessorClass(md, self.getConfigs())
-        md.treeprocessors.add("redlinks", ext, ">inline")
+        add_to_registry(md.treeprocessors, "redlinks", ext, ">inline")
 
 
 def makeExtension(*args, **kwargs):