Change your data structure a little bit (a better one, so that all levels are consistant), you can use some more generic code:

use warnings;
use strict;
use Data::Dumper;

my @array = qw/
comp1-cmd1-test1
comp1-cmd1-test2
comp1-cmd2-test1
comp2-cmd1-test1
comp2-cmd1-test2
comp3-cmd1-test1/;

my $hash = {};
for my $element (@array) {
    my @stuffs = split /-/, $element;
    insert($hash, \@stuffs);
}

print Dumper($hash);

sub insert {
    my ($hash, $stuffs) = @_;
    my $first_element = shift @$stuffs;
    $hash->{$first_element} = {} if (!defined($hash->{$first_element})
+);
    insert($hash->{$first_element}, $stuffs) if (@$stuffs);
}
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This gives:

$VAR1 = {
          'comp2' => {
                       'cmd1' => {
                                   'test1' => {},
                                   'test2' => {}
                                 }
                     },
          'comp3' => {
                       'cmd1' => {
                                   'test1' => {}
                                 }
                     },
          'comp1' => {
                       'cmd2' => {
                                   'test1' => {}
                                 },
                       'cmd1' => {
                                   'test1' => {},
                                   'test2' => {}
                                 }
                     }
        };
[download]