File Coverage

blib/lib/App/sdview/Parser/Markdown.pm

Criterion	Covered	Total	%
statement	114	126	90.4
branch	37	42	88.1
condition	20	27	74.0
subroutine	13	15	86.6
pod	0	4	0.0
total	184	214	85.9

#  You may distribute under the terms of either the GNU General Public License
#  or the Artistic License (the same terms as Perl itself)
#
#  (C) Paul Evans, 2021-2022 -- [e-mail]

use v5.26;
use warnings;

use Object::Pad 0.800;

package App::sdview::Parser::Markdown 0.13;
class App::sdview::Parser::Markdown
   :does(App::sdview::Parser)
   :strict(params);

use File::Slurper 'read_text';

use String::Tagged::Markdown;

use constant format => "Markdown";
use constant sort_order => 20;

=head1 NAME

C - parse Markdown files for L

=head1 SYNOPSIS

   $ sdview README.md

   $ sdview -f Markdown my-document

=head1 DESCRIPTION

This parser module adds to L the ability to parse input text in
Markdown formatting.

It uses a custom in-built parser for the block-level parts of the formatting,
able to handle comments, verbatim blocks, headings in both C<#>-prefixed and
C<=>-underlined styles, bullet and numbered lists, and tables.

It uses L to parse the inline-level formatting,
supporting bold, italic, strikethrough, and fixed-width styles, and links.

=cut

sub find_file ( $class, $name ) { return undef }

sub can_parse_file ( $class, $file )
{
   return $file =~ m/\.(?:md|markdown)$/;
}

method parse_file ( $fh )
{
   return $self->parse_string( read_text $fh );
}

field @_paragraphs;

sub _split_table_row ( $str )
{
   $str =~ m/^\s*\|/ or return undef;
   $str =~ m/\|\s*$/ or return undef;

   my @cols = split m/\|/, $str, -1;
   shift @cols; pop @cols;

   s/^\s+//, s/\s+$// for @cols;

   return \@cols;
}

method parse_string ( $str )
{
   my $in_verb;

   my @lines;

   foreach ( split( m/\n/, $str ), "" ) {
      my $line = $_; # So we have a copy, because foreach my ... will alias the readonly ""

      if( $in_verb ) {
         my $para = $_paragraphs[-1];

         if( $line =~ m/^\`\`\`/ ) {
            undef $in_verb;
            next
         }

         length $para->text and
            $para->text->append( "\n" );

         $para->text->append( $line );
         next;
      }

      if( $line =~ s/^\`\`\`// ) {
         my $language = $line =~ s/^\s+|\s+$//gr;
         push @_paragraphs, App::sdview::Para::Verbatim->new(
            language => ( length $language ? $language : undef ),
            text     => String::Tagged->new,
         );
         $in_verb++;
         next;
      }

      if( length $line ) {
         push @lines, $line;
         next;
      }

      while( @lines ) {
         if( $lines[0] =~ m/^