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package Dist::Zilla::Plugin::PodVersion 6.025;
# ABSTRACT: add a VERSION head1 to each Perl document

use Moose;
with(
  'Dist::Zilla::Role::FileMunger',
  'Dist::Zilla::Role::FileFinderUser' => {
    default_finders => [ ':InstallModules', ':ExecFiles' ],
  },
);

# BEGIN BOILERPLATE
use v5.20.0;
use warnings;
use utf8;
no feature 'switch';
use experimental qw(postderef postderef_qq); # This experiment gets mainlined.
# END BOILERPLATE

use namespace::autoclean;

#pod =head1 DESCRIPTION
#pod
#pod This plugin adds a C<=head1 VERSION> section to most perl files in the
#pod distribution, indicating the version of the dist being built.  This section is
#pod added after C<=head1 NAME>.  If there is no such section, the version section
#pod will not be added.
#pod
#pod Note that this plugin is not useful if you are using the
#pod L<[PodWeaver]|Dist::Zilla::Plugin::PodWeaver> plugin, as it also adds a
#pod C<=head1 VERSION> section (via the L<[Version]|Pod::Weaver::Section::Version>
#pod section).
#pod
#pod =cut

sub munge_files {
  my ($self) = @_;

  $self->munge_file($_) for @{ $self->found_files };
}

sub munge_file {
  my ($self, $file) = @_;

  return $self->munge_pod($file);
}

sub munge_pod {
  my ($self, $file) = @_;

  my @content = split /\n/, $file->content;

  require List::Util;
  List::Util->VERSION('1.33');
  if (List::Util::any(sub { $_ =~ /^=head1 VERSION\b/ }, @content)) {
    $self->log($file->name . ' already has a VERSION section in POD');
    return;
  }

  for (0 .. $#content) {
    next until $content[$_] =~ /^=head1 NAME/;

    $_++; # move past the =head1 line itself
    $_++ while $content[$_] =~ /^\s*$/;

    $_++ while $content[$_] !~ /^\s*$/; # move past the abstract
    $_++ while $content[$_] =~ /^\s*$/;

    splice @content, $_ - 1, 0, (
      q{},
      "=head1 VERSION",
      q{},
      "version " . $self->zilla->version . q{},
    );

    $self->log_debug([ 'adding VERSION Pod section to %s', $file->name ]);

    my $content = join "\n", @content;
    $content .= "\n" if length $content;
    $file->content($content);
    return;
  }

  $self->log([
    "couldn't find '=head1 NAME' in %s, not adding '=head1 VERSION'",
    $file->name,
  ]);
}

__PACKAGE__->meta->make_immutable;
1;

#pod =head1 SEE ALSO
#pod
#pod Core Dist::Zilla plugins:
#pod L<PkgVersion|Dist::Zilla::Plugin::PkgVersion>,
#pod L<AutoVersion|Dist::Zilla::Plugin::AutoVersion>,
#pod L<NextRelease|Dist::Zilla::Plugin::NextRelease>.
#pod
#pod =cut

__END__

=pod

=encoding UTF-8

=head1 NAME

Dist::Zilla::Plugin::PodVersion - add a VERSION head1 to each Perl document

=head1 VERSION

version 6.025

=head1 DESCRIPTION

This plugin adds a C<=head1 VERSION> section to most perl files in the
distribution, indicating the version of the dist being built.  This section is
added after C<=head1 NAME>.  If there is no such section, the version section
will not be added.

Note that this plugin is not useful if you are using the
L<[PodWeaver]|Dist::Zilla::Plugin::PodWeaver> plugin, as it also adds a
C<=head1 VERSION> section (via the L<[Version]|Pod::Weaver::Section::Version>
section).

=head1 PERL VERSION

This module should work on any version of perl still receiving updates from
the Perl 5 Porters.  This means it should work on any version of perl released
in the last two to three years.  (That is, if the most recently released
version is v5.40, then this module should work on both v5.40 and v5.38.)

Although it may work on older versions of perl, no guarantee is made that the
minimum required version will not be increased.  The version may be increased
for any reason, and there is no promise that patches will be accepted to lower
the minimum required perl.

=head1 SEE ALSO

Core Dist::Zilla plugins:
L<PkgVersion|Dist::Zilla::Plugin::PkgVersion>,
L<AutoVersion|Dist::Zilla::Plugin::AutoVersion>,
L<NextRelease|Dist::Zilla::Plugin::NextRelease>.

=head1 AUTHOR

Ricardo SIGNES 😏 <rjbs@semiotic.systems>

=head1 COPYRIGHT AND LICENSE

This software is copyright (c) 2022 by Ricardo SIGNES.

This is free software; you can redistribute it and/or modify it under
the same terms as the Perl 5 programming language system itself.

=cut