worked out some kinks in breadcrumb generation

doc/metadata-values.txt

@@ -4,6 +4,11 @@ aliases
 	(Obsidian standard metadata)
 	List of alternative names that can be used to link to a particular page.
 
+crumb_name
+    (Breadcrumbs extension)
+    The string to display as the title for this page when listed as a breadcrumb.
+    If not present, the page title is used.
+
 description
     (Obsidian Publish standard metadata)
     The description for this page.

src/dragonglass/extensions/breadcrumbs.py

@@ -1,6 +1,5 @@
 #!/usr/bin/env python3
 
-import re
 from typing import Any
 
 from ..extension import Extension
@@ -10,8 +9,6 @@ from ..tree import SourceNode, SourceIndex
 
 
 class Breadcrumbs(Extension):
-    LINK = re.compile(r'^\[\[(.+)(?:\|.+)?\]\]')
-
     def __init__(self, config: dict[str, Any]):
         """
         Initialize the Breadcrumbs extension.
@@ -35,9 +32,12 @@ class Breadcrumbs(Extension):
         if node.publish:
             target_str = node.metadata.get("parent", None)
             if target_str:
-                m = self.LINK.match(str(target_str))
-                if m:
-                    target_str = m.group(1)
+                target_str = str(target_str).strip()
+                if target_str[:2] == '[[' and target_str[-2:] == ']]':
+                    target_str = target_str[2:-2].strip()
+                    tmp = target_str.split('|')
+                    if len(tmp) > 1:
+                        target_str = tmp[0].strip()
                 if target_str == '.':
                     self._root_nodes.append(node)
                 else:
@@ -56,6 +56,17 @@ class Breadcrumbs(Extension):
             if target_node:
                 self._parents[node] = target_node
 
+    def _crumb_name(self, node:SourceNode) -> str:
+        """
+        Returns the "crumb name" for a node.
+
+        Args:
+            node (SourceNode): The source node to return the "crumb name" of.
+        """
+        if node in self._root_nodes:
+            return '.'
+        return node.metadata.get("crumb_name", node.page_title)
+
     def supply_template_vars(self, ctxt: Any, node: SourceNode) -> dict[str, Any] | None:
         """
         Called to supply additional template variables to the template to be rendered.
@@ -68,13 +79,12 @@ class Breadcrumbs(Extension):
             dict[str, Any]: If not ``None``, contains additional template variables to be added before
                 the template is rendered.
         """
-        breadcrumbs: list[dict[str, str]] = [{"name": "." if node in self._root_nodes else node.page_title,
-                                              "link": ""}]
+        breadcrumbs: list[dict[str, str]] = [{"name": self._crumb_name(node), "link": ""}]
         cur_node = node
         while cur_node not in self._root_nodes:
             cur_node = self._parents.get(cur_node, None)
             if not cur_node:
                 return None
-            breadcrumbs.insert(0, {"name": "." if cur_node in self._root_nodes else cur_node.page_title,
+            breadcrumbs.insert(0, {"name": self._crumb_name(cur_node),
                                    "link": self.link_target(ctxt, node, cur_node)})
         return {"breadcrumbs": breadcrumbs}