1 files changed, 97 insertions, 0 deletions
diff --git a/lib/Carton/Packer.pm b/lib/Carton/Packer.pm
new file mode 100644
index 0000000..dc1a2cf
--- /dev/null
+++ b/lib/Carton/Packer.pm
@@ -0,0 +1,97 @@
+package Carton::Packer;
+use Class::Tiny;
+use warnings NONFATAL => 'all';
+use App::FatPacker;
+use File::pushd ();
+use Path::Tiny ();
+use CPAN::Meta ();
+use File::Find ();
+
+sub fatpack_carton {
+    my($self, $dir) = @_;
+
+    my $temp = Path::Tiny->tempdir;
+    my $pushd = File::pushd::pushd $temp;
+
+    my $file = $temp->child('carton.pre.pl');
+
+    $file->spew(<<'EOF');
+#!/usr/bin/env perl
+use strict;
+use 5.008001;
+use Carton::CLI;
+$Carton::Fatpacked = 1;
+exit Carton::CLI->new->run(@ARGV);
+EOF
+
+    my $fatpacked = $self->do_fatpack($file);
+
+    my $executable = $dir->child('carton');
+    warn "Bundling $executable\n";
+
+    $dir->mkpath;
+    $executable->spew($fatpacked);
+    chmod 0755, $executable;
+}
+
+sub do_fatpack {
+    my($self, $file) = @_;
+
+    my $packer = App::FatPacker->new;
+
+    my @modules = split /\r?\n/, $packer->trace(args => [$file], use => $self->required_modules);
+    my @packlists = $packer->packlists_containing(\@modules);
+    $packer->packlists_to_tree(Path::Tiny->new('fatlib')->absolute, \@packlists);
+
+    my $fatpacked = do {
+        local $SIG{__WARN__} = sub {};
+        $packer->fatpack_file($file);
+    };
+
+    # HACK: File::Spec bundled into arch in < 5.16, but is loadable as pure-perl
+    use Config;
+    $fatpacked =~ s/\$fatpacked{"$Config{archname}\/(Cwd|File)/\$fatpacked{"$1/g;
+
+    $fatpacked;
+}
+
+sub required_modules {
+    my($self, $packer) = @_;
+
+    my $meta = $self->installed_meta('Carton')
+        or die "Couldn't find install metadata for Carton";
+
+    my %excludes = (
+        perl => 1,
+        'ExtUtils::MakeMaker' => 1,
+        'Module::Build' => 1,
+    );
+
+    my @requirements = grep !$excludes{$_},
+        $meta->effective_prereqs->requirements_for('runtime', 'requires')->required_modules;
+
+    return \@requirements;
+}
+
+sub installed_meta {
+    my($self, $dist) = @_;
+
+    my @meta;
+    my $finder = sub {
+        if (m!\b$dist-.*[\\/]MYMETA.json!) {
+            my $meta = CPAN::Meta->load_file($_);
+            push @meta, $meta if $meta->name eq $dist;
+        }
+    };
+
+    my @meta_dirs = grep -d, map "$_/.meta", @INC;
+    File::Find::find({ wanted => $finder, no_chdir => 1 }, @meta_dirs)
+        if @meta_dirs;
+
+    # return the latest version
+    @meta = sort { version->new($b->version) cmp version->new($a->version) } @meta;
+
+    return $meta[0];
+}
+
+1;