fix using custom variables starting with multiple underlines

Changes

@@ -3,6 +3,7 @@ This file documents the revision history for the Monitoring Webinterface Thruk.
 next:
           - fix recurring downtimes crontab entry for 2nd/3rd days of month
           - fix sessions removed early when using kerberos authentication
+          - fix using custom variables starting with multiple underlines
           - Rest:
             - add transformation and disaggregation functions
             - add support for timeperiod / time queries in where clause

MANIFEST

@@ -2309,6 +2309,7 @@ t/scenarios/backend_naemon/t/300-controller_extinfo.t
 t/scenarios/backend_naemon/t/300-controller_status.t
 t/scenarios/backend_naemon/t/300-controller_tac.t
 t/scenarios/backend_naemon/t/local/010-custom_vars_default_view.t
+t/scenarios/backend_naemon/t/local/020-custom_vars_filter.t
 t/scenarios/backend_naemon/thruk.conf
 t/scenarios/backend_naemon/thruk_local.conf
 t/scenarios/backend_nagios4/docker-compose.yml

lib/Thruk/Utils/Status.pm

@@ -1263,7 +1263,6 @@ sub single_search {
         }
         elsif ( $filter->{'type'} eq 'custom variable' ) {
             my $pre = uc($filter->{'val_pre'});
-            if(substr($pre, 0, 1) eq '_') { $pre = substr($pre, 1); }
             push @hostfilter,       { custom_variables => { $op => $pre." ".$value } };
             push @hosttotalsfilter, { custom_variables => { $op => $pre." ".$value } };
             my $cop = '-or';

t/scenarios/backend_naemon/t/local/020-custom_vars_filter.t

@@ -0,0 +1,36 @@
+use warnings;
+use strict;
+use Test::More;
+
+BEGIN {
+    use lib('t');
+    require TestUtils;
+    import TestUtils;
+}
+
+plan tests => 27;
+
+$ENV{'THRUK_TEST_AUTH'}               = 'omdadmin:omd';
+$ENV{'PLACK_TEST_EXTERNALSERVER_URI'} = 'http://127.0.0.1/demo';
+
+use_ok("Thruk::Utils::IO");
+
+###########################################################
+# verify that we use the correct thruk binary
+TestUtils::test_command({
+    cmd  => '/bin/bash -c "type thruk"',
+    like => ['/\/thruk\/script\/thruk/'],
+}) or BAIL_OUT("wrong thruk path");
+
+###########################################################
+TestUtils::test_page(
+    url  => '/thruk/cgi-bin/status.cgi?style=hostdetail&dfl_s0_type=custom variable&dfl_s0_val_pre=TEST&dfl_s0_op=%3D&dfl_s0_value=test var hst',
+    like => ['host=test'],
+);
+
+TestUtils::test_page(
+    url  => '/thruk/cgi-bin/status.cgi?style=hostdetail&dfl_s0_type=custom variable&dfl_s0_val_pre=_IMPACT&dfl_s0_op=%3D&dfl_s0_value=dbl underscore hst',
+    like => ['host=test'],
+);
+
+###########################################################