--- /dev/null
+#!/usr/bin/perl
+
+# Copyright 2018 Koha Development team
+#
+# This file is part of Koha
+#
+# Koha is free software; you can redistribute it and/or modify it
+# under the terms of the GNU General Public License as published by
+# the Free Software Foundation; either version 3 of the License, or
+# (at your option) any later version.
+#
+# Koha is distributed in the hope that it will be useful, but
+# WITHOUT ANY WARRANTY; without even the implied warranty of
+# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+# GNU General Public License for more details.
+#
+# You should have received a copy of the GNU General Public License
+# along with Koha; if not, see <http://www.gnu.org/licenses>
+
+use Modern::Perl;
+
+use Test::More tests => 1;
+use Test::Exception;
+
+use Koha::Account::Offsets;
+
+use t::lib::TestBuilder;
+
+my $schema = Koha::Database->new->schema;
+my $builder = t::lib::TestBuilder->new;
+
+subtest 'total_outstanding() tests' => sub {
+
+ plan tests => 4;
+
+ $schema->storage->txn_begin;
+
+ my $line = $builder->build_object( { class => 'Koha::Account::Lines' } );
+
+ my $amount_1 = 100;
+ my $amount_2 = 200;
+ my $amount_3 = -100;
+ my $amount_4 = -300;
+ my $amount_5 = 500;
+
+ my $offset_1 = Koha::Account::Offset->new(
+ { type => 'Fine', amount => $amount_1, credit_id => $line->id } )->store;
+ my $offset_2 = Koha::Account::Offset->new(
+ { type => 'Fine', amount => $amount_2, credit_id => $line->id } )->store;
+ my $offset_3 = Koha::Account::Offset->new(
+ { type => 'Payment', amount => $amount_3, credit_id => $line->id } )->store;
+ my $offset_4 = Koha::Account::Offset->new(
+ { type => 'Payment', amount => $amount_4, credit_id => $line->id } )->store;
+ my $offset_5 = Koha::Account::Offset->new(
+ { type => 'Fine', amount => $amount_5, credit_id => $line->id } )->store;
+
+ my $debits = Koha::Account::Offsets->search( { type => 'Fine', credit_id => $line->id } );
+ is( $debits->total, $amount_1 + $amount_2 + $amount_5 );
+
+ my $credits = Koha::Account::Offsets->search( { type => 'Payment', credit_id => $line->id } );
+ is( $credits->total, $amount_3 + $amount_4 );
+
+ my $all = Koha::Account::Offsets->search( { credit_id => $line->id } );
+ is( $all->total, $amount_1 + $amount_2 + $amount_3 + $amount_4 + $amount_5 );
+
+ my $none = Koha::Account::Offsets->search( { credit_id => $line->id + 1 } );
+ is( $none->total, 0, 'No offsets, returns 0' );
+
+ $schema->storage->txn_rollback;
+};