Proper broken link handler #385

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1. lucascool12

   added

   enhancementNew feature or requestNew feature or request

   on Mar 18, 2026
2. chrisjsewell commented on Nov 10, 2026

   

   chrisjsewell

   on Nov 10, 2026

   Member

   More actions

   Thanks for the request. There's no built-in callback (upstream markdown-it has none either), but you don't need to copy the link rule. Add a small inline rule before it that fills in missing references and lets the normal rule do the rest:

   from markdown_it.common.utils import normalizeReference
   
   def broken_link_plugin(md, resolve):
       def rule(state, silent):
           if state.src[state.pos] != '[':
               return False
           end = state.md.helpers.parseLinkLabel(state, state.pos, False)
           if end < 0 or state.src[end + 1:end + 2] == '(':
               return False
           label = state.src[state.pos + 1:end]
           key = normalizeReference(label)
           refs = state.env.setdefault('references', {})
           if key and key not in refs and (href := resolve(label)) is not None:
               refs[key] = {'href': href, 'title': ''}
           return False
       md.inline.ruler.before('link', 'broken_link', rule)
   
   md = MarkdownIt().use(broken_link_plugin, lambda label: f'/wiki/{label}')

   (Handle [text][label] by reading the second label the same way.) Closing as answered; feel free to reopen if that doesn't fit.
3. chrisjsewell

   closed this as completedon Nov 10, 2026