Bug 20126: Add simple test for ModBiblioMarc

Just to confirm that we see record length and base address in a record
that has been passed through ModBiblioMarc.

Test plan:
Run the test.

Signed-off-by: Marcel de Rooy <m.de.rooy@rijksmuseum.nl>

Signed-off-by: Nick Clemens <nick@bywatersolutions.com>

Signed-off-by: Jonathan Druart <jonathan.druart@bugs.koha-community.org>

t/db_dependent/Biblio/ModBiblioMarc.t

@@ -0,0 +1,49 @@
+#!/usr/bin/perl
+
+# 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 t::lib::Mocks;
+use t::lib::TestBuilder;
+use MARC::Record;
+
+use C4::Biblio;
+use Koha::Database;
+
+my $schema  = Koha::Database->new->schema;
+$schema->storage->txn_begin;
+
+subtest "Check MARC field length calculation" => sub {
+    plan tests => 3;
+
+    t::lib::Mocks->mock_preference( 'marcflavour', 'MARC21' );
+
+    my $biblio = t::lib::TestBuilder->new->build({ source => 'Biblio' });
+    my $record = MARC::Record->new;
+    $record->append_fields(
+        MARC::Field->new( '100', '', '', a => 'My title' ),
+    );
+
+    is( $record->leader, ' 'x24, 'No leader lengths' );
+    C4::Biblio::ModBiblioMarc( $record, $biblio->{biblionumber}, '' );
+    my $savedrec = C4::Biblio::GetMarcBiblio({ biblionumber => $biblio->{biblionumber} });
+    like( substr($savedrec->leader,0,5), qr/^\d{5}$/, 'Record length found' );
+    like( substr($savedrec->leader,12,5), qr/^\d{5}$/, 'Base address found' );
+};
+
+$schema->storage->txn_rollback;