Use Markdown::Perl for GitHub-style fenced code blocks (#57)#71
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#57) Text::MultiMarkdown has no support for GitHub-style fenced code blocks: a backtick fence was parsed as a single inline <code> span (collapsing the whole block onto one line) and ~~~ fences were ignored entirely. Switch the Markdown engine to Markdown::Perl in GitHub mode, which handles fenced code blocks (with language-foo info-string classes), tables, and the rest of GFM natively. This replaces an earlier hand-rolled fence preprocessor with a maintained CommonMark/GFM implementation. Markdown::Perl follows CommonMark and HTML-escapes " to " during conversion, which would stop Plerd::SmartyPants from curling literal double quotes; drop '"' from html_escaped_characters so quotes survive for SmartyPants (quotes inside code are still escaped via the separate html_escaped_code_characters option). SmartyPants is still required for curly quotes, dashes, and ellipses. Markdown::Perl requires Perl 5.26, so raise the floor in cpanfile. Also declare Capture::Tiny, a long-standing undeclared test dependency of t/init.t: it had been satisfied transitively through the Text::Markdown stack, so removing that stack exposed it. t/code_blocks.t covers backtick and tilde fences, language classes, line preservation, escaping, and untouched inline code. Co-Authored-By: Claude Opus 4.8 <noreply@anthropic.com>
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Closes #57.
Diagnosis
Text::MultiMarkdownonly understands indented (4-space) code blocks — it has no support for GitHub-style fences. A triple-backtick block was parsed as a single inline<code>span, so every line collapsed together (the reporter's "wrapped block of code rather than each line on a new line"), and~~~fences were ignored entirely.Approach
Rather than pre-processing fences by hand, swap the Markdown engine to
Markdown::Perlin GitHub mode. It's a maintained, pure-Perl CommonMark + GFM implementation that handles fenced code blocks (withlanguage-fooinfo-string classes), tables, and the rest of GFM natively. The hand-rolled fence preprocessor is gone.SmartyPants interaction
Markdown::Perlfollows CommonMark and HTML-escapes"→"during conversion, which would stopPlerd::SmartyPantsfrom curling literal double quotes into typographic ones. We drop"fromhtml_escaped_charactersso quotes survive for SmartyPants; quotes inside code spans/blocks are still escaped via the separatehtml_escaped_code_charactersoption. SmartyPants is still required (and kept) for curly quotes, en/em dashes, and ellipses —Markdown::Perldoes no typographic substitution of its own.Notes
cpanfile):Markdown::Perlrequires it.Makefile.PLis regenerated by Minilla at release, per the existing house pattern for dependency changes.cpanfile: dropText::MultiMarkdown, addMarkdown::Perl(pure Perl, no compiler/C library).CLAUDE.mdupdated to describe the new engine.Tests
t/code_blocks.tcovers backtick and tilde fences, language classes, line preservation, escaping, and untouched inline code. Full suite (84 tests) passes, including the existing MultiMarkdown table test.