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#!/usr/bin/perl

use strict;
use warnings;

use File::Basename qw( basename );

for my $subdir ( glob 't/*' ) {
    my %files;

    for my $file ( map { basename($_) } glob "$subdir/*.t" ) {
        my ($number) = $file =~ /^(\d+)/;
        next unless defined $number;

        push @{ $files{$number} }, $file;
    }

    for my $number ( grep { @{ $files{$_} } > 1 } keys %files ) {
        print $subdir, "\n";
        print '  - ', $_, "\n" for @{ $files{$number} };
        print "\n";
    }
}