mdwn: Don't enable alphabetically labelled ordered lists by default

This avoids misinterpreting initials ("C. S. Lewis was an author"),
the abbreviation for Monsieur ("M. Descartes was a philosopher") and
German page numbering ("S. 42") as ordered lists if they happen to
begin a line.

This only affects the default Discount implementation: Text::Markdown
and Text::MultiMarkdown do not have this feature anyway. A new
mdwn_alpha_list option can be used to restore the old interpretation.

1 files changed, 13 insertions, 0 deletions

diff --git a/IkiWiki/Plugin/mdwn.pm b/IkiWiki/Plugin/mdwn.pm
index e142fec46..9f06c03f2 100644
--- a/IkiWiki/Plugin/mdwn.pm
+++ b/IkiWiki/Plugin/mdwn.pm
@@ -41,10 +41,19 @@ sub getsetup () {
 			safe => 1,
 			rebuild => 1,
 		},
+		mdwn_alpha_lists => {
+			type => "boolean",
+			example => 0,
+			description => "interpret line like 'A. First item' as ordered list when using Discount?",
+			advanced => 1,
+			safe => 1,
+			rebuild => 1,
+		},
 }
 
 sub checkconfig () {
 	$config{mdwn_footnotes} = 1 unless defined $config{mdwn_footnotes};
+	$config{mdwn_alpha_lists} = 0 unless defined $config{mdwn_alpha_lists};
 }
 
 my $markdown_sub;
@@ -101,6 +110,10 @@ sub htmlize (@) {
 						$flags |= Text::Markdown::Discount::MKD_EXTRA_FOOTNOTE();
 					}
 
+					unless ($config{mdwn_alpha_lists}) {
+						$flags |= Text::Markdown::Discount::MKD_NOALPHALIST();
+					}
+
 					# Workaround for discount's eliding
 					# of <style> blocks.
 					# https://rt.cpan.org/Ticket/Display.html?id=74016