test(engine): add unit tests for Stop.pm

tests/Stop.t

@@ -0,0 +1,30 @@
+#!/usr/bin/env perl
+
+use strict;
+use warnings;
+use Test::More;
+use Test::MockModule;
+use lib '../lib/';
+use Nipe::Engine::Stop;
+use Nipe::Utils::Device;
+
+my $mock_device = Test::MockModule -> new('Nipe::Utils::Device');
+$mock_device -> mock('new', sub {
+    return (
+        'distribution' => 'debian', 
+        'username' => 'debian-tor'
+    );
+});
+
+my $mock_stop = Test::MockModule -> new('Nipe::Engine::Stop');
+$mock_stop -> mock('system', sub { return 1; });
+
+{
+    my $stop = Nipe::Engine::Stop -> new();
+    ok($stop, 'Stop module initialized correctly');
+}
+
+$mock_device -> unmock_all();
+$mock_stop -> unmock_all();
+
+done_testing();