You could use the keys function to test for the existance of any keys.

#!/usr/bin/perl

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

my $h = {
  'comp' => {
    'cmd' => {
      'tc1' => {
        platform_type => 'all',
        testsuite_type => 'all',
        view => 'private'
      },
      'tc2' => {
        platform_type => 'all',
        testsuite_type => 'all',
        view => 'private'}
      }
 }
};

delete $h->{comp}{cmd}{tc1};
delete $h->{comp}{cmd}{tc2};

unless (keys %{$h->{comp}{cmd}}){
  delete $h->{comp}{cmd};
}

unless (keys %{$h->{comp}}){
  delete $h->{comp};
}

print Dumper($h);

__DATA__
---------- Capture Output ----------
> "c:\perl\bin\perl.exe" _new.pl

$VAR1 = {};

> Terminated with exit code 0.
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